- Created by: sujjiiiii
- Created on: 09-12-16 20:58
Aim & Hypothesis
What is an aim?
- Refers to the intentions / purposes of the study
- Should make it clear what the study intends to investigate
- Must start with "to investigate"!
What is a hypothesis?
- A testable statement that (essentially) predicts what the researchers expect the study will find
- ONLY APPLIES TO EXPERIMENTS AND CORRELATIONS!
- Make sure you have a clear operationalization of both the IV and DV (i.e. the two conditions)
What is an experimental / alternate hypothesis?
- Will predict some sort of difference that will occur between the variables (Predicts the effect of the IV and DV)
What is a correlational hypothesis? (Only for correlational studies)
- Predicts that there will be a relationship between the variables
Types of Hypotheses
What is a one-tailed hypothesis?
- Predicts a specific direction of the results (DIRECTIONAL)
- e.g. "Participants who studied the word list (out of 10) in a silent atmosphere are likely to score significantly higher than those who studied the word list (out of 10) in a noisy atmosphere."
What is a two-tailed hypothesis?
- Predicts a difference / relationship will be found, but does not state what the difference will be (NON-DIRECTIONAL)
- e.g. "There will be a significant difference between the scores of participants who took a memory test (out of 10) in a silent atmosphere, or in a noisy atmosphere."
What is a null hypothesis?
- Predicts that there will be no significant difference / relationship will be found.
- e.g. "There will be no significant difference between the scores of participants who took a memory test (out of 10) in a silent or noisy atmosphere."
Quantitative and Qualitative Data
What is quantitative data?
Data that is numerical, it is objective
What is qualitative data?
Data that is written and is descriptive / in-depth, it is subjective
What are the advantages of quantitative data?
- Easy to analyse because quick and simple, comparisons can be made
- Objective data which supports 'psychology as a science' debate
- Encourages future funding and participation
What are the disadvantages of quantitative data?
- Does not show us the reasons for why certain behaviour was shown
What are the advantages of qualitative data?
- Gives us the reasons for why certain behaviour was shown
What are the disadvantages of qualitative data?
- It is open to interpretation and makes it subjective data
- Hard to analyse and replicate same / similar findings
Sampling Methods (Opportunity)
What is opportunity sampling?
- Method you make use of the people who are readily available to you and are willing to participate in the research that you're conducting
- e.g. If a psychologist wanted to study how many hours 16-18yr olds spend playing video games per week, they (the psychologist) would go to the nearest sixth form college to ask chosen target population (after gaining permission from the principle)
What are the advantages of opportunity sampling?
- Easy, quick, cheap and most economical way of sampling
- Participants are readily available
- Can therefore obtain a large sample quickly
What are the disadvantages of opportunity sampling?
- Likely to gain a biased sample due to the selecting of a sample from a limited area; the area that is openly available to you
- Therefore it is not very representative to the wider target population
Sampling Methods (Volunteer)
What is volunteer / self-select sampling?
- Method that involves advertising your research and collecting a sample of people who want to take part in the research you're conducting (i.e. they voluntarily decide whether they'll take part or not)
- e.g. Placing an advert in the college cantine which asks for 20 people (aged 16-18) to take part in a reseach which is studying whether music effects memory or not
What are the advantages of volunteer / self-select sampling?
- Can obtain a wide range of participants
- Can be convenient as well as ethical, if it leads to informed consent
What are the disadvantages of volunteer / self-select sampling?
- Typically unrepresentative to the wider target population because people do not usually respond to adverts unless they have a great interest in psychology
- Because of this interest in psychology, demand characteristics are likely to be given during the study which reduces the internal validity
Sampling Methods (Random)
What is random sampling?
- When every member of the target populations has an equal chance to be selected to participate within the study. Draws, lots or the use of computers are typically used so that the participants' names are randomly selected until the desired number is gained. Participants are then contacted and asked if they want to take part
- e.g. If a psychologist wanted to research how many 16-18yr olds played video games from a college in Manchester, they (the psychologist) would access the student database of the college (with all of the student names) and would then use a random number generator to select a sample of students randomly; they would then contact those students, asking if they wanted to take part
What are the advantages of random sampling?
- Least biased method as everybody has an equal chance in being selected
What are the disadvantages of random sampling?
- Can be very time-consuming to do, especially with large samples
- This is because if one person does not wish to participate in the study, then the process of drawing lots / using a random number generator has to be restarted in order to maintain the equal chance of people being selected to participate in the study
Sampling Methods (Snowball)
What is snowball sampling?
- Used when the target population is not easy to contact and is achieved when a participant is asked to suggest someone else (who is willing / appropriate) for the study
- e.g. If a psychologist wanted to study those who use drugs, they may find a participant who is a drug user and then ask them to suggest someone they know to participate in the study that they are in currently
What are the advantages of snowball sampling?
- Useful in obtaining populations that are hard-to-track; such as drug users, alcoholics, criminals etc.
- Therefore ethical because you are not manipulating the fact that someone is a drug user
What are disadvantages of snowball sampling?
- No way in knowing whether the sample is representative to the wider target population
- It is typically biased as the sample will end up being friends of those who had suggested the study
Ethics (the Four Principles)
What is the British Psychological society (BPS)?
- An organisation that sets ethical guidelines for those involved in conducting psychological research. These ethical guidelines outline what is and isn't acceptable when conducting research and has a code that is based on four principles: respect, competence, responsibility and integrity.
What is respect?
- Ensuring that participants have given informed consent, have the right to withdraw, and that their details (personal or not) are kept confidential if asked
- Psychologists are expected to respect individual, cultural and role differences; such as a participant's age, gender, education background, language, race, religion, sexual orientaiton, marital or family status, disability and socio-economic status
- Psychologists should also avoid practices that may come across unfair or prejudiced
What is competence?
- Maintaing the high standards of competence in their professional work
- Psychologists should develop and maintain a comprehensive awareness of professional ethics
- Therefore requiring psychologists to follow the ethical guidelines in order to uphold psychology's name; therefore encouraging future research
Ethics (the Four Principles) [cont]
What is responsibility?
- Ensuring that participants are protected from mental and/or physical harm, and are debriefed after having participated in a study
- Psychologists are expected to uphold their name (as psychologists) and must avoid the misuse (or abuse) of their contributions to society
What is integrity?
- Ensuring that participants are not decieved during a study
- Psychology values the idea of psychologists being honest, accurate, clear and fair with their interactions with all participants
- Also maintaing / upholding psychology's name
Ethics - Ethical Guidelines
What is informed consent?
- Ensuring that participants are aware of anticipated consequences of any research participation, what the study entails, and what its purpose is
- Should be given at the beginning of the research
- If participant is under 16, then consent must be obtained via parents or guardians
What is the right to withdraw?
- Ensuring that participants can withdraw from the study at any point in the study
- If participants wish for their data and/or recordings to be destroyed, then psychologists must meet this demand as participants have a right to do so
What is confidentiality?
- Privacy of participants should be respected; the names or details of the participants should not be released, and all results or infortmation regarding to specific individuals must be kept confidential
- In observations, participants must be observed in a public place
- Participants should be made aware where any breech of confidentiality may occur
Ethics - Ethical Guidelines [cont]
What is protection of participants?
- Ensuring that no physical or mental (psychological) harm is brought upon the participant(s); they (the participants) should leave in the same state that they arrived in
What is deception?
- Intentional deception, such as deliberately lying to the participant(s) (i.e. misleading them about the aim(s) of the study) must be avoided as much as possible, unless it is necessary in exceptional circumstances to preserve the integrity of the research
What is debriefing?
- A way to overcome the breaching of an ethical guideline (or more); it is usually done at the end of a study, and it is the researcher's responsibility to tell the participant all the necessary pieces of information that they need to complete their understanding of the study
- It is necessary that the researcher ensures that there has been no physical and/or mental harm done to the participant, and should this occur, the participant must receive the necessary treatment to aid them
- If the participants have been deceived in any way, or have not consented towards the research, then the researcher(s) must FULLY EXPLAIN the true purpose.
What is validity?
- Refers to the aim of the study; can the measurement be applied to real life? It is the overall accuracy of the study
- There are different types of validity...
- Checking whether any effects observed within the study are due to the manipulation of the IV and not other factors (i.e. extraneous variables)
- Focuses on the procedures and measures used within the study; if these are accurate, then it is possible to state a true cause and effect
- Can be increased by having a high level of control over extraneous variables and making the use of standardised procedures (so that all participants experience the same thing)
- Generalising beyond the study; making sure that the factors outside of the study are representative
- Can be increased by making use of real-life situations, or using the random sampling method to gather a range of participants
- There are two types of external validity; ecological and population
Validity [cont 1]
- Checking whether the study can be generalised to real life or not (i.e. does the task within the study reflect a task done in real life?)
- Can be increased by making use of a natural setting within the experiment (i.e. less controls), and using tasks that are realistic
- Checking whether the sample is representative to the wider target population
- Can be increased with large samples in order to get a range of people / characteristics
- Checking whether a measurement tool looks like it will measure what the behaviour is intended to measure; it focuses on the procedures and measures used in the study
- e.g. Does an IQ test really measure how smart someone is?
- Can be increased by high level of controls over extraneous variables, making use of standardised procedures
Validity [cont 2]
- Checking whether scores from a test can predict other forms of behaviour
- e.g. In Casey's study of delayed gratification, she used Walter Mischel's participants 40 years later (when they were adults) to predict whether high/low delayers could control impulses when they were adults
- Can be increased with the use of quantitative data to establish different patterns
- Checking whether a measurement tool measures all aspects of the study
- e.g. Does a driving test measure hazard perception, driving skills, etc?
- Can be increased by making use of a pilot study in order to identify any issues; can also be increased by gathering quantitative and qualitative data
- Checking whether the current measuring tool correlates with previous measurement tools of the same behaviour (i.e. the results from a study have been consistent / have a positive correlation)
- e.g. A person's score a new IQ test should be the same score on the old IQ test that they took a week ago
- Can be increased by the reduction of researcher bias
What is reliability?
- Reliability refers to the idea of the study being consistent or having the potential to be replicated
- There are different types of reliability...
- Checking whether the study is standardised and whether it can be replicated again and again; making sure that all participants undergo the same experience within the study
- Can be increased by having a highly standardised procedure (DO NOT REFER TO HIGH LEVEL OF CONTROLS IN YOUR ANSWERS IF THE QUESTION ASKS HOW YOU WOULD INCREASE THE INTERNAL RELIABILITY!)
- Internal reliability can be assessed by using the spilt-half method...
- Checking whether two halves of a questionnaire are similar (i.e. gives consistent answers)
- e.g. Putting in repeat questions within a questionnaire to check how reliable the participants are being when answering the question(s)
- Can be increased by only measuring ONE aspect of behaviour per measure
Reliability [cont 1]
- Checking whether the results of the study can be replicated if the study was to be carried out again
- e.g. If a participant took an IQ test on Monday and got a score of 100, then took the same IQ test a week later and got the same score, then the IQ test is a reliable / consistent measure of IQ
- Can be increased by taking more than measurement of behaviour
- Can check for external reliability by checking for test-retest and inter-rater reliability...
- Testing the participants more than once in order to get the same or similar scores on the same test
- e.g. If a participant takes an IQ test, scores 107, and then later on in the year, they take a new established IQ test and scores 107 again, it means that the test is a reliable measure of that person's IQ
- Can be increased by increasing external reliability
Reliability [cont 2]
- Checks whether two or more observers have high agreement (80% or above 0.8%) on a score, therefore meaning that the measurement of behaviour (or measuring tool) is reliable
- In an observation, this would mean that if there is more than one person observing the same behaviour / individual in the same way, and they should agree on the behaviour measured to obtain inter-rater reliability
- e.g. If I wanted to conduct an observation to see how couples express their intimacy when in a coffee shop, I could conduct a pilot study and have one or two fellow observers to observe the intimate behaviour between couples by using a coding frame, and after having completed the observation, we can check how many times we saw the behaviours being shown and either agree or disagree as to whether the behaviour on the coding frame is appropriate for the true / final observation
- Can be increased by fully operationalising and using coding frames to CLEARLY identify behaviour(s)
Intro: Experiments & Variables
What is an experiment?
- A method of investigation to which there is an IV and a DV (there can be more than one of each)
- Purpose of any experiment is to establish a true cause and effect; psychologists want to control all variables bar the variable that they are manipulating (i.e. the IV)
- Before an experiment begins, it is necessary that the researcher(s) formulate a hypothesis, making sure that it is operationalised in order to make sure that nobody is left uncertain as to how they (the researcher(s)) intend to manipulate or measure a variable
What is a variable?
- There are three types of variables; the IV, the DV and extraneous variables
- IV is the variable that is directly manipulated by the researcher (the 'cause')
- DV is the variable that is measured by the researcher (the 'effect')
- Extraneous variables are factors that have not been controlled and therefore become confounding variables in the study; the researcher must control these extraneous variables as they have the potential to interfere with the relationship of the IV and DV
- There are three types of extraneous variables...
What are situational variables?
- Anything within the environment that has the potential to impact participant behaviour or the results of the study
- e.g. Background noise, temperature of the room, whether participants have eaten or not, time of day, etc.
- Situational variables will effect the internal validity of the study
What are individual differences?
- Refers to the differences between the paticipants that have not been accounted for and could therefore impact the results of the study
- e.g. The level of IQ, the span of a participant's memory, the complexity of words used in the task / instructions may differ between different individuals, the age of participants, etc.
- Individual differences can be controlled by using repeated measures or a matched pairs experimental design
Extraneous Variables [cont 1]
What are researcher effects?
- When the researcher acts differently towards different participants, or in different conditions
- e.g. Whether participants are children / adults (i.e. the complexity of words will vary, as well as the tone of voice of the reseacher), the clarity of instructions may vary depending on who the participants are, etc.
- Researcher effects can influence different behaviours, such as demand characteristics
How do you control extraneous variables?
- You can control extraneous variables by ensuring you have implemented the appropriate controls, as well as doing a single- or double- blind study
- A single-blind study is when the participants are unaware of the aim(s) of the study
- A double-blind study is when the PARTICIPANTS are still unaware of the AIM(S) of the study, and the RESEARCHERS are unaware of which conditions the participants have experienced
- Bear in mind that all extraneous variables decrease internal validity, as well as internal and external reliability
Experimental Methods (Lab)
What is a lab experiment?
- A highly-controlled experiment that has artificial setting, set up for the purpose of the investigation
- The reseacher directly manipulates the IV and controls any extraneous variables
- All participants should be randomly allocated to the experimental conditions; the researcher should not decide which condition participants should go into as bias may occur
What are the advantages of a lab experiment?
- Because of the high levels of control within the experiment, extraneous variables are easily controlled and therefore enables a true cause and effect to be established
- High levels of control also allows replication of the study, and the ability to test for the reliability / replicability of the study
What are the disadvantages of the study?
- Due to the high level of controls, it lowers the study's ecological validity as it is hard to generalise to real life (because it is artificial), and therefore makes the study less useful
- It also increases the chance of demand characteristics, lowering the internal validity of the study
Experimental Methods (Quasi)
What is a quasi experiment?
- A highly-controlled experiment that has a naturally occurring IV
- Therefore participants' conditions cannot be manipulated due to ethical reasons
What are the advantages of a quasi experiment?
- As the IV is naturally occurring, it enables the researcher to study behaviour that would be unethical to manipulate
- Due to the high controls, there is high control over extraneous variables, which allows a true cause and effect to be established
What are the disadvantages of a quasi experiment?
- The researcher cannot control the participants' individual differences such as their social background, their IQ... this decreases the internal validity of the research as they can become confounding variables
- There is a lack of ecological validity due to the high control over the experiment, which means that the study may not be able to be generalised to real-life
Experimental Methods (Field)
What is a field experiment?
- An experiment that is carried out in the natural environment of those whose behaviour is being studied e.g. participants' homes, the classroom, a nursey
- The researcher still manipulates the IV and measures the DV, but there are lower levels of controls
- Participants are typically unaware that the study is taking place
What are the advantages of a field experiment?
- They offer a more realistic setting of the study and therefore have an increased amount of ecological validity
- Because participants are unaware that the study's taking pace, there's a reduced chance of demand characteristics occurring, increasing the internal validity of the study
What are the disadvantages of a field experiment?
- Due to the lack of control, there is a chance that other factors could be influencing the behaviour of participants
- As participants are unaware of the study taking place, there are ethical issues such as informed consent that could damage psychology's reputation
Experimental Designs (Independent Measures)
What are independent measures?
- When there are two or more experimental conditions to which different participants take part in each conditions
- Participants are randomly allocated into each condition
What are the advantages of independent measures?
- There are no risks of order effects as each participant tested only once in one condition
- It reduces the chance of demand characteristics because each person is tested once and hence has less opportunity to work out the hypothesis
- Has increased internal validity
What are the disadvantages of independent measures?
- Because there are different participants in each of the experimental conditions, it is likely that the extraneious variable of individual differences will occur, decreasing the internal validity
Experimental Designs (Repeated Measures)
What are repeated measures?
- When only one group of participants take part in all experimental conditions
What are the advantages of repeated measures?
- It is more economical as fewer participants are needed
- There is no risk of individual differences as the same participants undergo each and every one of the experimental conditions; this increases the internal reliability
What are the disadvantages of repeated measures?
- There is a risk of demand characteristics because the same participants undergo each and every one of the experimental conditions and may therefore work out the aim of the research
- There is a risk of order effects to which participants become fatigued in doing the same / similar tasks in each of the differing conditions, or they may become better in completing the task due to practice of it
- To rid of order effects in a repeated measures design, use counterbalancing; this is when you vary the order of the conditions to the participants; e.g. condition A is given to half of the participants first, then condition B is given to the other half of the participants second; then the groups swap the conditions
Experimental Designs (Matched Pairs)
What are matched pairs?
- When the participants are paired up with someone else within in the sample who has the same characteristics such as: age, gender, intelligence level, agression level, etc.
- One of the pair is tested in the experimental condition, and the other is tested in the control condition
What are the advantages of matched pairs?
- There are no risks of order effects, individual differences or demand characteristics because participants are only being tested once; this increases the internal validity
What are the disadvantages of matched pairs?
- It is often time consuming for the researchers to find participants who have the same characteristics; e.g. if researchers wanted to match participants by IQ level, it would be necessary to carry out an IQ test for each and every one of the participants in order to match each one into pairs based upon their IQ level
What is a controlled observation?
- An observation that is usually carried out in a lab - and has high level of control - which has a standardised procedure such as a coding frame
- Paricipants are randomly allocated to each condition
What are the advantages of a controlled observation?
- Collects quantitative data by using the pre-determined list of behavious and is therefore easy and quick to carry out
- There are high levels of control over extraneous variables due to the artificial setting, increasing the internal validity
What are the disadvantages of a controlled observation?
- It lacks in ecological validity because of the artificial setting and therefore cannot be generalised to real-life
- There is a risk of demand characteristics as they may be able to guess what behaviour the researcher wants to observe
What is a naturalistic observation?
- An observation that is carried out in the natural surroundings of the participant(s) that focuses on their naturally occurring behaviour
What are the advantages of a naturalistic observation?
- It is high in ecological validity because participants are in their natural environment, therefore encouraging their natural behaviour - this makes the research generalisable to real-life
What are the disadvantages of a naturalistic observation?
- Because there is a lack of control, there is an increased chance that extraneous variables may occur, thus making the research limited as other factors have affected the behaviour and not the IV; i.e. there is no cause and effect
What are structured observations?
- An observation that is carried out with the use of a coding frame, without direct involvement with the participants
What are the advantages of a structured observation?
- It simplifies data recording due to the checklist of behaviours - it also encouarages inter-rater reliability to be established, increasing the accuracy of the study
What are the disadvantages of a structured observation?
- By having a pre-determined list, it is likely that some critical behaviours could be missed during the observation and weren't on the pre-determined list, decreasing the accuracy of the study
What are unstructured observations?
- An observation where there is no pre-determined checklist and so the researcher notes down all behaviour observed
What are the advantages of unstructured observations?
- Provides good insight as the observation collects qualitative data
- All behaviours are taken into account
What are the disadvantages of unstructured observations?
- Because it is qualitative data, it is hard to analyse as well as to replicate
- It is likely that the observer will note down eye-catching behviours, leaving other potential critical behviours behind
- It is also likely that participants may be suspicious that they are being observed
What is a covert observation?
- When the participants are unaware that they're being observed by a researcher
What are the advantages of a covert observation?
- Because participants are unaware that they're being watched, the researcher has access to view their natural behaviour - their 'real' behaviour - especially if it's carried out in their natural surroundings
- There is less chance of demand characteristics occurring, therefore increasing the usefulness of the study, as well as the internal validity of the study
What are the disadvantages of a covert observation?
- It breaks the ethical guideline of informed consent as participants have not agreed to be observed because they do not know that they're being watched
- It is likely that the observer may appear suspicious as they have to take notes of the types of behviour being observed; they (the researcher) may have to rely on their memory in order to look less suspicious, decreasing the internal validity of the research as their memory of the behaviour being observed might not be accurate
What is an overt observation?
- An observation where the participant is aware that they're being observed and has therefore given consent to be observed
What are the advantages of an overt observation?
- It enables ethical research to be carried out, therefore increasing psychology's reputation as it is respected, therefore enabling future research to be taken place
- The researcher can openly make notes and does not have to rely on their memory
What are the disadvantages of an overt observation?
- Because the participants are wary that they're being watched, they may produce demand characteristics to suit what they think the observer wants
- It is not necessary representative to the wider target population as those who are interested in psychology may accept to participate in the observation / research
What is a non-participant observation?
- An observation where the observer is not a member of the group being studied, or is pretending to be a part of another person in the group that is being studied
What are the advantages of a non-participant observation?
- The data collected will not be biased as they are observing the group as an 'outsider', they will feel less sympathy for the participants
- If done covertly, then there is a decreased risk of demand characteristics as participants are behaving naturally
- If done overtly, then there is no issue in breaking ethical guidelines
What are the disadvantages of a non-participant observation?
- The data collected may be less accurate as the observer is observing from a distance (they are external); they may not have a full view on the participants, decreasing the validity of the study
What is a participant observation?
- When the observer is part of the group being studied and is playing the role / pretending to be a participant
What are the advantages of a participant observation?
- It enables the researcher to have a good view / insight of the observations as the researcher is internal within the group; because of this, they can gather accurate data as they are involved in the events - this increases the validity of the study
What are the disadvantages of a participant observation?
- The observer may become too involved in the events of the observation and therefore could influence behaviour e.g. the observer may recognise that a certain person is not typically quiet and could therefore purposely talk to that person in order to make them speak
- If the researcher is pretending to be a participant, it can be hard to remain hidden as they have to be involved in the events that occur in order to blend in with the group; if the observer is spotted, demand characteristics could occur, or, because there are many events happening within the group, the observer may have no / little time to note the observed behaviours down
What is time sampling?
- When the observer records what the participant(s) is / are doing in the use of pre-determined time intervals
What are the advantages of time sampling?
- It decreases researcher fatigue as they (the researcher) don't have to constantly observe the behaviour(s) from the participants
What are the disadvantages of time sampling?
- It is likely that the researcher could miss critical behaviour when not observing in the fixed time intervals; this reduces the validity and accuracy of the study
What is event sampling?
- When the observer records what the participant(s) is / are doing consistently without being interrupted
- The researcher(s) also make use of a coding frame
What are the advantages of event sampling?
- It is unlikely for the researcher(s) to miss behaviour as they are consistently observing it without being interrupted; therefore they make note of every behaviour they see and thus they collect valid data as all occurrences of behaviour is being noted
What are the disadvantages of event sampling?
- Because the researcher(s) use coding frames, critical behaviours that are not on the pre-determined checklist may be missed, decreasing the internal validity
- As the researcher(s) is / are constantly watching behaviour, it is likely that participants may get suspicious, making the researcher(s) likely to get caught
What is a correlational study?
- A statistical technique used by psychologists to see if there is a relationship between two variables
- There is no IV or DV, but rather, co-variables
What are the advantages of correlational studies?
- They allow the psychologists to statistically analyse naturally occurring events
- It enables the researcher(s) to measure the relationship between variables that would be unethical or impossible to manipulate experimentally
- Can be used to support the scientific credibility of research
- It can be used for pilot studies i.e. check for reliability and validity of a study
What are the disadvantages of correlational studies?
- It does not necessarily mean causation as there is a chance that extraneous variables have impacted the cause of the results; this means you cannot state a true cause and effect
What is the correlation co-efficient?
- It's the strength of the correlation, i.e. whether the correlation is positive or negative, or 0 (no correlation)
Writing Hypotheses for Correlations
How to write a one-tailed hypothesis for a correlational study...
- Instead of saying "there will be significantly more or less...", say: "there will be a positive correlation between..."
How to write a two-tailed hypothesis for a correlational study...
- Instead of saying "there will be a significant difference..." say: "there will be a significant relationship between..."
How to write a null hypothesis for a correlational study...
- Instead of saying "there will be no significant difference / effect / link..." say: "there will be no significant correlation between..."
MAKE SURE THAT YOUR VARIABLES ARE FULLY OPERATIONALISED!
What is a self report?
- Where the participants provide data for the researchers by completing questionnaires, surverys, interviews and/or doing a rating scale
- Enables the researcher to understand what the participants' thoughts and feelings are
What are the advantages / disadvantages of a self report?
- The advantages of a self report vary based upon what KIND of self report the researcher is conducting, i.e. if they are conducting an interview or a questionnaire.
What is a questionnaire?
- A set of questions that can be completed on pen and paper, on the internet or over telephone
What are the advantages of a questionnaire?
- It is quick and easy to gather a great deal of data from a large sample, this makes it cost- and time-effective
- There is no risk of researcher effects if the questionnaire is completed by pen and paper or the use of the internet as the researcher is not present
- If open questions are used, the researchers can gather good insight into the individual responses from the participants
What are the disadvantages of a questionnaire?
- It is open to some desirability bias as participants may give answers that themselves look better or choose answers that seem more favourable
- If the researcher is not present, then the participant cannot ask for the question to be rephrased to make them understand, and so they may not give an accurate answer; this decreases the internal validity of the research
What are the advantages of interviews?
- Participants are capable in asking for the question to be repeated or explained further should they struggle to understand the question as the interviewer is present, meaning that the respondent will give a legitimate / meaningful answer, increasing the validity and usefulness of the data collected
- It is possible to gain insight on participants' answers since they can explain their answers, especially in unstructured interviews
What are the disadvantages of interviews?
- They can be time-consuming seeing as the researcher has to administer the interview itself, in terms of designing the questions for all participants (especially if the interview is a structured one), as well as taking notes from the participants' answers
- Because the researcher is present, social desirability bias may occur, influencing participants' answers to make them appear more favourable
- Researcher effects may occur as the researcher's expectations, or the way they phrase the questions may influence the respondents' answers, decreasing validity and making the study limited
Types of questions - closed & open
What is a closed question?
- A question that has a limited range in what responses the participants can choose from (i.e. they force the participants to chose from a set of fixed choice answers)
- They can be analysed by descriptive statistics such as the mean, median and mode
- Closed questions are typically in the form of: tick lists, 'select the most applicable', rating scales, likert scales and semantic differential scales
What are the advantages of closed questions?
- They provide quantitative data, which enables the researcer to collect a great deal of data quickly and easily; it is also easy to analyse as well as replicate (i.e. it increases external reliability)
- The results can also be easily summarised and compared between participants and conditions
What are the disadvantages of closed questions?
- They restrict the answers given by the respondent and therefore the researcher cannot gain insight as to how the participants truly feel (i.e. it is quantitative data that is being recorded)
- The respondent may also become frustrated to the limited choice of answers, and this may affect their attitude towards the research being carried out
- Lacks ecological validity because it is not a day-to-day task to be forced to make choices they wouldn't make in real-life
- The misinterpretation of a question can go unnoticed, and central tendencies may occur
Types of questions - closed & open
What is an open question?
- Open questions are questions that allow the participant to respond in their own words (i.e. they are not restricted into responding with just a "yes"/"no")
- They usually take the form of a question that encourages the participant to give their opinion... 'why do you think some people don't obey the law and continue to use their mobile phone, without using a hands-free kit whilst driving?'
What are the advantages of open questions?
- Psychologists are able to gather rich, detailed information and therefore have increased realism (i.e. validity) as respondents are not forced to answer in a particular way - therefore gives more insight
- The freedom to respond removes the negative feelings participants have when forced to choose from a limited range of questions
What are the disadvantages of open questions?
- It is harder to analyse and compare responses to open questions since data needs to be coded (or quantified) in some way to do so, and this may not be easy to do (coding / quantifying the qualitative data collected, that is)
- It is difficult to establish the reliability of qualitative responses
- Participants may also give socially desirable answers, decreasing reliability
Designing a good questionnaire
How do you design a good questionnaire?
- 'Filler questions' - hide the purpose of the study, avoiding demand characteristics as well as social desirability bias. This, therefore, increases the validity of the study.
- Arranging the questions - start with easier questions and end with harder questions throughout the questionnaire. This lets the respondent relax, allowing them to answer easily instead of being stressed (should the questionnaire begin with a hard question) which could cause them to misinterpret the questions given, or even answer the questions inaccurately, thus affecting the validity.
- Pilot Studies - enables the researcher to test for validity and reliability as they can check whether; participants understand the terminology of the questions used, emotive questions have been used - causing the participant to become defensive and thus invalidating their answers, any difficulties are present - such as having too many questions and making participants bored, or if leading questions have been used - causing a bias in participant answers. Pilot studies also allow the researcher to make adjustments before they conduct the true study, thus saving their time and money.
Designing a good questionnaire [cont]
Do ethics play a part in making a good questionnaire?
- Yes, ethics play a very big part when designing any type of study. There are four principles that a researcher must consider when designing a questionnaire...
- Protection of participants: participants should not be asked embarrassing questions, and should be reminded that they do not HAVE to answer questions if they don't want to.
- Protection of participants / informed consent: participants should be given a full debrief at the end of the questionnaire, along with any sort of access to help on issues that may have been raised from answering the questions to ensure protection from harm.
- Confidentiality: questionnaires are often anonymous, and the names of the participants should not be recorded. This should be clearly stated at the start of the questionnaire.
- Right to withdraw: participants should be aware that once the questionnaire has been submitted, they WILL lose their right to withdraw.
What is an interview?
- Interviews are similar to questionnaires since they ask participants questions, however, the difference between the two is how the researcher asks the participants questions; i.e. the researcher asks the questions him/herself via telephone or face-to-face rather than giving the questions in written form. There are three types of interview that the researcher can choose from...
What is a structured interview?
- An interview which has pre-determined questions BEFORE the interview takes place, these (questions) are carefully planned to encourage specific responses from the participant
- The same questions are given in the same order to each and every participant
- The researcher will often not show any interest or expression to prevent influenced answers from the participants... they will also avoid deviating from the questions
What are the advantages of structured interviews?
- They are easy to replicate and analyse, as well as draw out trends from participants' answers, due to the data being quantitative
Structured Interviews [cont]
What are the disadvantages of structured interviews?
- Due to the procedure being very standardised, the researcher ignores any lines of interest, even if the participant responds with an interesting answer
- The interview itself is artificial, and could make the respondent feel like they're not free to add or explain their answers, thus making the data collected limited
- The fact that it is so standardised means that the study would lack ecological validity
What is an unstructured interview?
- An interview that runs very much like a 'free flowing' conversation, meaning the researcher will ask spontaneous questions
- Though the questions are spontaneous, the researcher may have a few structured questions to start off the interview
- The questions asked are based upon the participants' previous answer
What are the advantages of an unstructured interview?
- Participants' answers are more detailed, allowing the researcher to gather rich, qualitative data, and therefore provides the researcher good insight into what the participants' thoughts and feelings are, increasing the validity of the study
- The researcher can also gather a wider range of answers since every participants' answer will be different
- Because conversations occur on a day-to-day basis, the ecological validity of the study will be increased
What are the disadvantages of an unstructured interview?
- Because there is such a broad range of topics being discussed, it can be hard to summarise the data gathered, as well as analyse and draw out trends etc., therefore decreasing the reliability
What is a semi-structured interview?
- It is a compromise between a structured and unstructured interview, meaning that there are SOME set questions (in order to keep the focus on the specific study), but also spontaneous questions that deviate from the actual topic
What are the advantages of a semi-structured interview?
- This type of interview collects both qualitative AND quantitative data, allowing easy access to insight AND analysis
- It enables the participant to have a friendly and sociable conversation with the researcher, as well as allowing the researcher to also move onto the original topic after veering off any interesting lines of conversation with the interviewee
What is a peer review?
- A peer review is a process that occurs after research has been conducted in order to assess the validity of it (the study) before it is published
- It is reviewed by psychologists who are not involved in the research, but who are working in the similar field
- There are three purposes of a peer review...
1. Allocation of research funding - they are decisions about what research should be funded
2. Publication of research - academic journals provide scientists with the opportunity to share the results of their research. Only research that passes peer review is published, preventing incorrect or faulty data entering the public domain
3. Assessing university departments - all university science departments are assessed in terms of quality (Research Excellence Framework (REF)). Future funding for the department depends on whether the university has received good ratings from the REF peer review
What are the advantages for a peer review?
- It can help retain the credibility of a university with new research and checks the validity of the research before being published, meaning no false information will be passed into the public domain
Peer Reviews [cont]
What are the disadvantages of peer reviews?
- Because it is done anonymously, the reviewers can use their position of anonymity to their advantage in terms of harshly criticising rival research; they can sometimes make their rival's research fail in order to take the latter's ideas and carry out the same piece of research themselves
- Sometimes the reviewer can have a biased opinion, opposing the researcher's opinion in the study, i.e. if the study was based on the nature / nurture debate and favoured the nature side, then a reviewer may prefer the nurture side and thus fail the given research
- 'Institution bias', this means that, typically, research from prestigious universities are favoured
- There is a big issue on gender bias, as male researchers are favoured
- The 'file draw phenomenon' is something where peer reviews which have positive results are favoured (i.e. research that supports the alternate hypothesis); many negative findings (i.e. research that supports the null hypothesis) are either not published, or are left in the researcher's drawer, thus distorting our understanding of the subject
Citing Academic References
What is citing an academic reference?
- Citing an academic reference is when you use another researcher's knowledge in your own work, you are basically acknowledging their research / theories / models
- It is a way of 'thanking' the author for using their research to help construct the purpose of your research
- By referencing, you can enable other people to access what YOU have used to help your work, as well as allow your readers to read the referenced articles
- It protects you from being accused of plagiarising someone else's work as you have acknowledged the fact that you have looked at someone else's work in order to help your own work
What is Harvard Referencing?
- This is the most common method of referencing for books or journals
- To do a Harvard Referencing of a book, you should...
1. Include all of the authors' names, for example, "Boring, E.G"
2. Include the date IN BRACKETS after completing the above. e.g. "Boring, E.G. (1929)"
3. Include the title of the book, this must be in ITALICS. e.g. "Boring, E.G. (1929) A History of Experimental Psychology"
4. Include the publisher, location, edition, and any page numbers of the pages you paraphrased research from. They must be seperated by the correct punctuation mark. e.g. "Boring, E.G. (1929) A History of Experimental Psychology, New York: Century. Page 20."
Citing Academic References [cont]
How do you do a Harvard Referencing for a journal article?
- If you use the original research paper, then it must be referenced. To do this, you need to...
1. Include the surname and the intial(s) of the author(s). e.g. "Grant, H. M., Lane, C., Bredahl, J. C., Clay. J., Ferrie, J., Groves, J. E., McDorman, T. A & Dark, V. J."
2. Include the year in BRACKETS. e.g. "Grant, H. M., Lane, C., Bredahl, J. C., Clay, J., Ferrie, J., Groves, J. E., McDorman, T. A & Dark, V. J. (1998)"
3. Include the name of the journal article. e.g. "Grant, H. M., Lane, C., Bredahl, J. C., Clay, J., Ferrie, J., Groves, J. E., McDorman, T. A & Dark, V. J. (1998) Context-dependent memory for meaningful material: information for students."
4. Include the name of the journal in ITALICS. e.g. "Grant, H. M., Lane, C., Bredahl, J. C., Clay, J., Ferrie, J., Groves, J. E., McDorman, T. A & Dark, V. J. (1998) Context-dependent memory for meaningful material: information for students. Applied Cognitive Psychology"
5. Include the volume number, the issue number (IN BRACKETS), and the first and last page numbers. e.g. "Grant, H. M., Lane, C., Bredahl, J. C., Clay, J., Ferrie, J., Groves, J. E., McDorman, T. A & Dark, V. J. (1998) Context-dependent memory for meaningful material: information for students. Applied Cognitive Psychology, 12, (6), 617-623."
Writing a report
How do you write a report?
- To write a report, you must include the following:; title, contents, abstract, introduction, aim, hypothesis, method, results, discussion, references, appendix
- Each of these features are important and you need to know what they do
What is the title?
- The title informs the reader exactly what the report is about
What does the section 'abstract' mean?
- The abstract is a brief, overall summary of 150-250 words of the report itself. It covers the aim, method, results and conclusion in a very concise fashion
What does the section 'introduction, aim and hypothesis' include?
- The introduction is designed to introduce the reader to the topic area and background to the study, it is largely made up from the relevant theories and past studies / research relevant to the report
- It should have; the overview of the area, 3 specific research studies, how the said studies relate to your aim, operationalised IV(s) and DV(s) which lead to an alternate hypothesis, and finally, a null hypothesis
What is the 'method'?
- The method describes how the study was conducted and includes the; design, apparatus, participants, standardised procedure and controls
Writing a report [cont 1]
What does the subsection 'design' (under the section of 'method') include?
- The design is a subsection under the section of 'method'
- It includes the details of your design, i.e. did you use a repeated measures design? What your IV(s) and DV(s) is / are and how are they operationalised?
- You should also describe (in detail) about the decisions you made to design your research
- You need to identify expected extraneous variables, and how they might become confounding variables and how you may control these variables
What does the subsection of 'apparatus' include?
- This includes what materials and resources you used
What does the subsection of 'participants' include?- This is where you state your target population, the selection method, the sex of your participants, their age, background, and the method of application to your experimental conditions
What does the subsection of 'standardised procedure' include?- This is essentially the instructions on how you conducted your study, you bullet-point your steps clearly
- You must ensure that your steps are very clear as you want your readers to obtain the same results as you should they decide to conduct your study
Writing a report [cont 2]
What does the section 'results' include?
- This section is where the findings of your study are reported
- Your results should be reported in a clear and accurate way
- It must include descriptive statistics, i.e. the mean, median, mode and range
What does the section 'discussion' include?
- It begins with a summary of the findings of the results, before exploring the best explanations of the given findings whilst considering possible weaknesses and improvements, as well as the implications of the research and suggestions for future research
What does the section 'reference(s)' include?
- This is where the author of the report gives the details of all the research documents, journals, internet sources and books they have cited in their report
- It involves using the Harvard Referencing system
What does the section 'appendix / appendicies' include?
- This includes all raw data, statistical calculations and resources / materials that were used in the study
Types of data and central tendencies
What is primary data?
- Data that is collected from the participants directly from the researcher(s)
What are the advantages of primary data?
- It may be considered to be more trustworthy since the data collected has more validity compared to secondary data as the researcher has gone through all careful planning to gather the data needed
- The researcher operationalises the IV in order to represent what is being measured - by taking this care to do this, primary data is, in general, valid since the study is designed and carried out for the main purpose of research
What are the disadvantages of primary data?
- Expensive to obtain because each researcher or research team has to start from the beginning of a study and follow the whole study through, finding participants, organising materials and running the study
- Limited to the time, place and number of participants etc., whereas secondary data can come from different sources to give more range and detail.
What is secondary data?
- Data that has already been gathered by someone else other than the researcher(s)
Types of data and central tendencies [cont 1]
What are the advantages of secondary data?
- It saves time since the researcher(s) do not need to go through the trouble of starting a study from the very beginning in order to gather the results needed
- It also saves money as the researcher(s) do not need to invest in special equipment / participants to help them gain their results
Types of data and central tendencies [cont 2]
What are the disadvantages of secondary data?
- Unlike primary data, which is collected with a concrete idea in mind, secondary data has been collected by someone else in order to answer different research questions or objectives
- In addition, secondary data is considered to be inappropriate since the information might refer to a different country, meaning the difference in cultures (such as collectivist or individualist ones) might not make your study valid
What is the mean?
- A measure of central tendency which is calculated by adding up all the scores in the set, and dividing by the number of the scores
What are the advantages of the mean?
- All data is used to generate the final answer so is more precise
What are the disadvantages of the mean?
- If there is a large data set, then it is time-consuming to calculate the mean
- If there are any rogue outliers in the set, it can distort the mean majorly
What is the median?
- The median is where all the scores from the set are put into numerical order, and then taking the central point from this set of scores
Types of data and central tendencies [cont 3]
What are the advantages of the median?
- It marginalises the anomalies to give a more reflective / representative average
What is the disadvantage of the median?
- It takes a very long time to calculate the median if there is a very large set of data, meaning that it may not accurately reflect the data set
What is the mode?
- A measure of central tendency in which records the most frequently occurring score in a set
What are the advantages of the mode?
- Extreme values will not distort the value
What are the disadvantages of the mode?
- There may be more than one modal value, making the data less reliable
- Or, there may not be a modal value at all
What is the range?
- Where you take the biggest value away from the smallest and add 1
Types of data and central tendencies [cont 4]
What are the advantages of the range?
- Easy to calculate
What are the disadvantages of using the range?
- Doesn't take into account all values
- Doesn't indicate whether numbers are closely grouped around the mean or spread out evenly
- Anomalies can affect the range greatly
- Least precise measure
Presenting Data (Graphs)
Why might you use a tally chart?
- You might use a tally chart to collect and record raw data, and then develop the said data into a graph
What is discrete data?
- Discrete data is when the units of measurement cannot be split up, for example, there is nothing between 1 CD and 2 CDs
- It can be placed into distinct catergories
What is continuous data?
- Continuous data has a scale of measurement, like a thermometer, there is meaning at all points between the numbers (like temperature)
- It cannot be placed into distinct catergories
What types of graphs use represent discrete data?
- Bar charts
- Pie charts
What types of graphs represent continuous data?
- Line graphs
- Scatter diagrams
Presenting Data (Graphs) [cont]
What are the rules for drawing graphs?
- For all graphs, you must make sure to have the following; title, two fully labelled axis, correct scale
How do you draw a histogram?
1. Calculate the class boundaries, so where each group begins; e.g. if the groups are: (age) 5-10, 11-15, 16-17 and over 17 (the frequency for each one, in that order, is: 6, 15, 4 and 0), then the class boundaries are: 5, 11, 16 and 18
2. Work out the class widths, this is the distance BETWEEN the class boundaries, essentially, you subtract the class boundaries from one another. It tells us how much data is between the class boundaries; e.g. the first class width would be the distance between 5 and 11, which is 6. The next would be 11 and 16, which is 5, then 16 and 18 = 2.
3. The final step is to work out the frequency density. This is the frequency of values divided by the class width of values. The formula for this is: frequency density = frequency / width. In our example, this would be; 6 divided by 6 = 1, 15 divided by 5 = 3, and 4 divided by 2 = 2.
4. The values, 1, 3 and 2 are the values of the frequency density. Frequency density goes on the y axis, making the height for the columns that go on the y axis.
How do you draw a pie chart?
1. Reprsent each part of the data as a proportion of 360, since there are 360 degrees in a circle. e.g. if 55 out of 270 participants said that twitter was their favourite social media, we would represent this on the circle as a segment with an angle of (55 / 270) x 360 = 73 degrees.
2. The formula for this is: (n / total) x 360
What is variance?
- A measure of dispersion and tells us about the spread of scores around the mean.
- A small variance would suggest that the scores are all similar and close to the mean, whereas a large variance would suggest that the scores are at a larger distance from the mean.
How do you calculate variance?
1. Calculate the mean of your scores from the data
2. Subtract the mean from each number in the data set
3. Square the result of these calculations
4. Add the square numbers together to find the sum of squares
5. Divide sum of squares by n(or n - 1 if it is sample variance) (n = the number of data sets you have)
What are the strengths of variance?
- Precise measure of dispersion (better than the range) because all exact values are taken into account
What are the weaknesses of variance?
- Can hide anomolies and is not as precise as the standard deviation
What is standard deviation?
- Standard deviation is the square root of variance and therefore tells us whether the scores are similar or different from one another from the mean
How do you calculate standard deviation?
You square root your answer from your population or sample variance calculation.
What are the strengths of standard deviation?
- Most precise measurement of dispersion
What are the weaknesses of standard deviation?
- It is quite difficult to calculate
- Not useful unless data is normally distributed
Levels of measurement
What is nominal data?
- Data that is put into categories (i.e number of males or females)
What are the advantages of nominal data?
- Easy to generate from closed questions
- Large amounts of questions can be collected quickly, increases the external reliability
What are the disadvantages of nominal data?
- Without a linear scale, participants may be unable to express their degrees of response
- Can only use the mode as a measure of dispersion
What is ordinal data?
- Data that has been put into rank order (i.e. positions in a race; 1st, 2nd, 3rd)
What are the advantages of ordinal data?
- Indicates relative values on a linear scale instead of just totals, so is more informative than nominal data
What are the disadvantages of ordinal data?- Do not know how large the gap is between 1st and 2nd place, or between 2nd and 3rd or if these gaps are equal
Levels of measurement [cont]
What is interval data?
- Data that has known units with equal distances between the points on the scales (i.e. time taken in seconds, measurement in feet and inches, marks out of 100 of a knowledge test, temperature)
What are the advantages of interval data?
- More informative than ordinal and nominal as the points are directly comparable because they are all of equal value
- Scientific measures used to record the distance between values are highly reliable
Probability and significance levels
What is probability?
I- Refers to how likely something is to happen and is often expressed as a number between 0 and 1. A probability of 1 means something is certain to happen, whereas a probability of 0 means that it is impossible for something to happen.
Choosing a significance level...
(Levels of significance are written as 'p' values). If there is less than 5% probability that our results were due to chance, then we can consider it significant...
- P ≤ 0.05 means that the probability that results are due to chance is equal to or less than 5%
If psychologists want to be more certain about their results than this, they could choose a stricter significance level...
- P ≤ 0.01 means that the probability that results are due to chance is equal to or less than 1%
They might even choose something stricter such as...
- P ≤ 0.001 meaning that the probability that results are due to chance is equal to or less than 0.1%
OVERALL, AS THE PROBABILITY OF RESULTS BEING DUE TO CHANCE INCREASES, THE SIGNIFICANCE OF RESULTS DECREASES!
Type 1 and type 2 errors
What is a type 1 error?
- When the researcher is too lenient and mistakingly accepts the alternative hypothesis when they should accept the null hypothesis and reject the alternative hypothesis.
What is a type 2 error?
- When the researcher is too strict and mistakingly accepts the null hypothesis when they should accept the alternative hypothesis and reject the null hypothesis.
Key facts to remember
Observed value = number produced after applying an inferential test formula
Critical value = the list of numbers that inform you whether an observed value is significant or not - there is a different table for each different stats test
For Spearman's Rho and Chi-Squared, the observed value has to be greater than the critical value, for the rest, the observed value must be less than the critical value
The assumptions for parametric tests are...
- Populations drawn should be normally distributed
- Variances / standard deviation of populations should be approximately equal
- Should have at least interval data
- Should be no extreme scores
When do you use the Mann Whitney U test?
- When the data collected is either ordinal or interval
- When an independent measures design is used
When do you use the Chi-Squared test?
- When the data collected is nominal
- When an independent measures design is used
When do you use the Wilcoxon test?
- When the data collected is either ordinal or interval
- When a repeated measures design is used
When do you use the Binomial test?
- When the data collected is nominal
- When a repeated measures design is used
When do you use the Spearman's Rho test?- When the data collected is ordinal or interval
- When a relationship is being explored