Psychological Investigations

AS OCR Psychology - Psychological Investigations 

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  • Created on: 01-04-12 16:15

General Things You Need To Know

Hypotheses (Only in Experiment and Correlation) 

1. Experimental/Alternate/Research Hypothses - predicts there will be a difference in results between the conditions. 

E.g. Gender & Memory 

1 Tailed - Males will perform better on a memory test than females, as measured by the number of photos correctly recalled out of 20. 

2 Tailed - There will be a difference between males and females and their performance on a memeory test, as measured by the number of picture correctly recalled out of 20. 

2. Null Hypotheses - predicts there will be no difference betwwen the conditions.

E.g.

There will be no difference between males and females and their performance on a memory test, as measured by the number of pictures they can recall out of 20. 

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General Things You Need To Know

Independent and Dependent variables 

IV - the thing that you change betwwen the conditions 

DV - thing that you meaure 

Confounding Varables (Extraneous variables) - factors that were not controlled but that could affect the results e.g. participants mood. 

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General Things You Need To Know

Sampling Techniques 

Oppourtunity Sampling  - using whoever is avaliable at the time from the given population. 

+  Not time consuming  - the sample may be biased e.g. all girls 

Random Sampling - every person in the given population is out into a list and their names are randomly picked. e.g. putting names in a hat. 

+  everybody in the population has an equal chance of being picked       

- doesn't guarantee a sample that is totally representitive of the popultion

Self - Selected (volunteer) sampling  - involves participants electing themselves often through an advert (e.g. Milgram) 

+ - people have gvien their consent (ethics), esay to get sample and less time consuming  - most of the target population are unlikely to respond, respondents atypical, sample would probably be biased. 

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General Things You Need to Know

Quantitative and Qualitative Data 

Quantitative Data - numbers, percentages, quantites etc.. 

+ easily comparable, more reliable, objective  - lacks depth, less valid 

Qualitative Data - meanings, understandings, words etc.. 

+ detailed, more valid, increaed depth, more subjective  - often smaller samples, less reliable, more subjective, harder to generalise

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General Things You Need To Know

Descriptive Statistics 

Mean - average, add all scores together and / by how many there are

Median - middle value, if even number add two middle numbers together and / by 2 

Mode - most frequently occuring value

Nominal data - data that was seprate catergories 

Ordinal data - ordered in some way e.g. ask people to list their favourite football teams in preference order 

Ratio data - true zero point and equal interval between two points on a scale 

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General Things You Need To Know

9 Ethical Issues:

1. Consent 

2. Confientiality 

3. Collegues - if you observe a collegue conducting unethical research, you are                        obliged to report them 

4. Deception 

5. Debrief 

6. Withdrawl from investigation 

7. Giving Advice - cant give psychological advice unless you qualified to 

8. Protection of participants 

9. Observation - you are allowed to observe people withouth their consent if its                             in a place where they would ordinarily be observed 

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Self-Report

Self-report methods are investigative techniques that focus on the participants perspective. They are more likely to produce findings that reflect one participants point of view. The main two types are questionnaires/surveys and interviews. 

There are 3 types of rating scales: 

1. Bi-Polar Rating scale - Involves having answers the go from one end of a scale to another.

E.g. How would you rate Disco Dancing?

  Brilliant      Good    Okay    Poor    Rubbish   

       =              =          =          =            =   

+ easy to compare data  

- fixed responses: 'impose a framework on the participants reality' 

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Self-Report

2. Checklist Rating scale - Involves giving participants a list of things that can choose from, as to what applies to them.

E.g. What do you enjoy doing at the weekend?

seeing friends/ cinema/ swimming/ listening to music/ working 

+ produces quantitative data, whcih is easy to compare 

- fixed responses: 'impose a framework on the participants reality' 

3. Graphical Rating scale - involves giving participants a scale. 

E.g. How do you feel about testing beauty products on animals? 

   |                   |                   |              + participants are able to more acurrately  Angry        Neutral         Happy            reflect their feelings

                                                          - difficult to compare findings 

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Self-Report

Open and Closed Questions 

Open Questions - questions that don're require a fixed repsponse 

+ participants can write what they feel, produces qualittative data 

- difficult to compare 

Closed Quesitons - have fixed responses 

+  produces quantitative data so easy to compare 

- fixed responses, 'impoe a framework on the participants reality'. 

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Self-Report

Strengths and Weaknesses of Self-Report 

Quesstionaries and Surveys:

+ Record the participants experiences 

+ Response rate can be high 

+ Can sample a very large target population 

+ Can contain questions on issues that are difficult to talk about 

- Often Influenced by bias; difficult to design well 

- Response rate can be low 

- The data gathered can be complex and be difficult to interpret

- Participants may not answer answer truthfully 

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Self-Report

Interviews: 

+ Provide large amounts of qualitative data

+ Enable the researcher to respond to the participants experiences 

+ More likely to gain an insight into the participants world 

+ Can use body language to confirm verbal response 

- Difficult to carry out 

- May be influenced by experimenter biased 

- Can be difficult to analyse 

- Take a long time to carry out 

-Participants may not answer truthfully 

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Self-Report

What is meant by Reliablity? 

Conducting the test more than once and getting the same results (consistent results) 

How could you ensure that your questions/questionnaire/interview was reliable?

Use the same set of questions and same set of instructions that you fie to the participants and give them the all the same amount of time to complete the task. 

What is meant by Validity? 

When something measures what it claims to measure.

How could you ensure that your questions/questionnaire/interview was valid? 

Ensuring questions are specific and focused on the topic in hand. 

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Observation

Participant Observation - Observer gets invovlved in the study

Non-participant - observer 'sits back' and observes behaviour

Covert - observer is 'undercover'

Overt - Participants are aware of observation

Structured - behaviour is broken up into categories and a checklist is used

Unstructured (naturalistic) - natural situation is studied 

Direct observation - the observer directly observes the behaviour 

Indirect observation -observations of data, such as observing TV adverts

Time sampling - observer decides on a time interval, such as once a minute, and the observer notes any behaviour and this interval. 

Event sampling - observer keeps account of each time a particular behaviour is observed. 

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Observation

Behaviour checklist/coding system (e.g. Bandura = aggression). 

  • should be objective 
  • cover all possible component behaviours & avoid 'waste basket' category
  • shouldn't have any overlapping categories

Participant Observation:

  • Identify specifics - how to record the behaviour, e.g. behaviour checklist/coding system/record on camera/microphone... 
  • small pilot study 
  • ethics e.g. consent, access - how do you ask permission to 'enter the environment'? 

Structured Observation:

  • coding system/behaviour checklist 
  • time/even sampling 
  • who/where/when/why?
  • Inter-rater reliability  
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Observation

Strengths of Observation: 

1. A means of conducting preliminary investigations in a new area of research, to produce hypotheses for future investigations. 

2. Able to capture spontaneous & unexpected behaviour 

Weaknesses of Observation: 

1. Observers may 'see' what they expect to see - observer bias 

2. Poorly designed behaviour checklist/coding system reduces reliability (low inter-rater reliability) 

Ethical issues of observation

Informed Consent, right to withdraw, protection from harm, deception, debrief. 

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Observation

Reliability - how consistent any measure is. 

How could you ensure the your observation was reliable? 

Behaviour checklist could be used by 2 different researchers then checked for accuracy. 

Validity - extent to which research has measured what it intended to measure.

How could you ensure that your observation is valid?

Using more than 1 observer & averaging data across observers to balance out any bias. 

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Experiment

An experiment involves the manipulation and measurement of variables. For example, in a lab experiment the researcher manipulates one variable and then measures the affect on another variable. 

Possible experimental hypothesis: gender and memory 

One Tailed Experimental Hypothesis - Males will perform better than females on a memory test as measured by the number of pictures correctly recalled out of 20. 

Two tailed Experimental Hypothesis - There will be a difference between males and famles and their performance on a memory test, as measured by the number of pictures recalled out of 20. 

Null Experimental Hypothesis - There will be no difference between males and females and their performance on a memory test as measured by the number of pictures correctly recalled out of 20. 

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Experiment

Possible Independent and Dependent variables in an experiment, how each could be measured and an alternative way of measuring: Gender and Memory 

Independent Variable = gender

                                   = measured by asking participants 

                                   = alternative way of measuring could be to observe                                                     participants

Dependent Variable = memory 

                                 = measured by showing 20 pictures and seeing how many                                         they can recall

                                 =  alternative was of measuring could be showing 20 words                                          and seeing how many they can recall  

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Experiment

Writing an appropriate procedure: 

Aims

Hypotheses

Population

Sampling

Technique

Sample

Test

Administrate

Collate

Data 

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Experiment

Appropriate descriptive statistics:

Calculate the mean, median and mode for each condition, and place into tables an bar charts. 

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Correlation

Positive and negative correlation 

Positive Correlation - as one variable increases the value of the other variable will also increase. 

Negative Correlation - as one variable increases the value of the other variable will decrease. 

Scattergraphs show correlation between 2 sets of data. The extent to of the correlation is described using a correlation coefficient, whcih is a number between +1 and -1. 

Hypotheses: 

  • One tailed hypothesis - There will be a negative relationship between how people perceive the attractiveness of an animal, as measured by a Bi-Polar rating scale, and how old they are, as measured by the number of years since they were born. 
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Correlation

  • Two tailed hypothesis - There will be a relationship between how people perceive attractiveness as measured by a Bi-polar rating scale, and how old they are, as measured by the number of years, since they were born. 
  • Null hypotheses - There will be no relationship between how people perceive attractiveness, as measured by a Bi-polar rating scale, and how old they are, as measured by the number of years since they were born. 

Strength of Correlation: 

  • allows researchers to investigate topics that would not be available otherwise due to it being unethical, such as looking at factors linked to child abuse. 

Weakness of Correlation: 

  • it is difficult to produce a cause and effect as a correlation only looks at the relationship between variables and may not take all the other factors into account. 
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