Aims: An aim identifies the purpose of the investigation. It is a straightforward expression of what the researcher is trying to find out from conducting an investigation. The aim typically involves the word “investigate” or “investigation”.
Example: To descibe the effects of stress on memory.
Hypothesis: A hypothesis is a precise testable statement of what the researchers predicts will be the outcome of the study.
Types of hypothesis:
- Null Hypothesis
- Alternative Hypothesis
- Directional Hypothsis
- Non Directional
Null Hypothesis: states that there is no relationship between the two variables being studied.
Example: Our memory will not be affected by stress, any changes will be due to chance.
Alternative Hypothesis:states that there is a relationship between the two variables being studied. There are two types: directional and and non-directional
Directional: predicts the nature of the effect of the independent variable on the dependent variable.
Example: The more stressed you are the worse their memory will be
Non Directional: predicts that the independent variable will have an effect on the dependent variable, but the direction of the effect is not specified.
Example: There willl be a difference in memory, when stress levels increase
Sampling: A sample is the group of people who take part in the investigation. The people who take part are referred to as “participants”. There are 3 types of sampling.
- Random Sampling
- Opportunity Sampling
- Volunteer Sample
Random Sampling: Every Member of the target population has an equal chance of being included in the sample
- It's unbiased
- Risk of being Skewed even if it is mathmatically unbiased
Opportunity Sampling: A very common method of sampling is to use whoever is available at the time.
- Time saving and efficient
- The sample will be biased and unrepresentative
Volunteer Sampling: consists of participants becoming part of a study because they volunteer when asked or in response to an advert.
- Participants will be motivated
- Sample will be personality biased as they all chose to volenteer
Expermiental Design: Is how participants are allocated to the different conditions (or IV groups) in an experiment. There are 3 types of experimental design.
- Repeated Measures
- Independent Groups Design
- Matched Pairs Design
Repeated Measures: Participants are expossed to all conditions.
- No Individual Differences
- Order effects and Demarnd Characteristics
Independent Group Design
Independent Group Design: Participants are only expossed to one condition.
- No Order Effects
- Individual Differences.
Matched Pair Design
Matched Pair Design: Participants are paired with another participant in a diffferent condition and matched on a variable where their results are compared.
- There is no order effect or demarnd characteristics.
- Individual differences and time consuming matching participants.
Ethics in research
Ethics: Ethics in research ensure the safety of participants. Participants may be human or animals, both of which have guidelines that need to be met.
Human guidelines: For human participants the overriding principle is that there must be no physical or psychological harm to participants
Animal guidelines: For animals ensure they are protected, pain must be minimised and they must be well cared for.
The Role of the Researcher and Participant's right
The role of the Researcher: The researcher must always act in a professional manner, making sure that the best interests of the participants, and of society in general, are met.
Participants Rights: Researchers must always maintain respect for the participants. Participants’ rights include; Conﬁdentiality, Voluntary Participation, Withdrawal Rights, Informed Consent,
Confidentiality:This means that participants must not be identiﬁed in any way in terms of test results, their involvement in the study or any other conﬁdential data. For Example participants would be represented as a figure instead of individuals.
Voluntary Participation and Withdrawal Rights
Voluntary Participation: Participants have the right to refuse to take part in a study. There must not be any pressure to take part in a study, nor should they be tricked into taking part by deception.
Withdrawal Rights: Participants have the right to leave a study at any stage, regardless of the possible effects on the results. They also have the right to withdraw their results after the study has been completed. This must be explained to the participants before beginning the study.
Informed concent and Deception
Informed Consent: Participants must be given information about a study before they agree to take part. For participants who are either too young or too intellectually disabled to give their consent, their guardian must be given the information before giving consent on their behalf.
Deception: in Research This is only permitted if the results would be confounded if the participants had much information before taking part in the study. The researcher must ensure that participants do not unexpectedly suffer distress; the study must be stopped immediately if this occurs. Participants must be debriefed when the study is complete.
Debriefing: Debrieﬁng occurs after completion of the study and participants are told the results and conclusions of the study. Any erroneous beliefs about the study are corrected, especially if there was any deception involved. Participants are informed of the availability of, and how to obtain, counselling if they feel they need it
Reliablity and Validaty
Reliablity: Is the consistency of the Research. Is it able to be repeated?
Internal Validaty: Internal validity refers to whether the effects observed in a study are due to the manipulation of the independent variable and not some other factor.
External Validaty: External validity refers to the extent to which the results of a study can be generalized to other settings (ecological validity), other people (population validity) and over time (historical validity).
Lab Experiment and Field Experment
Lab Experiment: This type of experiment is conducted in a well-controlled environment – not necessarily a laboratory – and therefore accurate and objective measurements are possible.
Field Experiement: These are conducted in the everyday (i.e. natural) environment of the participants but the situations are still artificially set up.
Natural Experiment and Case Study
Natural Experiment: In a natural Experiment, rather than Direct manipulation, the research takes advantage of a naturally occurring change in an IV. There is NO control other than the control already in place.
Case Study: Case studies are in-depth investigations of a single person, group, event or community.
Natural Observation: Observed in a natural environment, e.g. school or workplace
Lab-based observation: Labs can be ‘dressed up’ to look more natural, like a playroom, where children can be observed using a one-way mirror
Questionaires: Are a type of Self Reprt technique. They can be thought of as a kind of written interview.
Closed Questions: Allow limited responce.
Open Question: There is more oppurtunity to answer freely.
Interviews: They are Similar to questionaires in the way they are both self report techniques. However, interviews tend to be face to face.
Stuctured: There is a fixed, predetermined set of questions that are put to every participant in the same order and in the same way. The interviewer stays within their role and maintains social distance from the interviewee.
Unstructured: There are no set questions and the participant is given the opportunity to raise whatever topics he/she feels are relevant and ask them in their own way. In this kind of interview much qualitative data is likely to be collected.
Quantative and Qualative Research
Quantative Research: Quantitative research gathers data in numerical form which can be put into categories, or in rank order, or measured in units of measurement. This type of data can be used to construct graphs and tables of raw data.
Qualative Research: Qualitative research gathers information that is not in numerical form. For example, diary accounts, Open ended questions, unstructures interviews and unstructured observations. Qualitative data is typically descriptive data and as such is harder to analyze than quantitative data.
Mode, Median and Mean
Mode: The most frequently occuring number in a set of scores.
Median: The central number in a set of scores
Mean: The Average of the set of scores
Measures of Dispersion
Range: IS the simples measure of dispersion and is caculated by finding the lowest and the highest scores in the data.
Semi-Interquartile Range: The Semi-interquatile range is often preferred to the range because it is less sensitive to extreme scores. it measures the score which lie in the middle 50% of the range.
Standard Deviation: Tells us the mean distance of scores from tge neab if a set if scores. A large standard Deviation shows that there is a wide spread in the range.
Presenting the Data:
Table of the scores,
Frequency polygon and
Bar Charts, Histograms and Frequency Polygons
Bar Charts: These are used for data which come in categories. Each thing can only fit in one category
Histograms: Similar to a a bar chart. However Histograms deal with continous data, meaning the variable on the horizontal axis is a scale, instead of categories.
Frequency Polygons: A frequency polygon is similar to a histogram, however the mid point of the bars would have been joint with a continuous line.
Scattergraphs: Are used to display data when a study is correlational. This means the relationship is being investigated.
Positive Correlations: As one variable increases the other also increases.
Negative Correlations: As one variable increases the other decreases
Zero Correlations: There appears to be no correlations