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Formal Research Methods

Psychological Investigations. Formal Research Methods. This session. 3 Types of experiments…. Laboratory experiment- these are conducted under highly controlled conditions to avoid extraneous or confounding variables eg : noise from effecting the results.

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Formal Research Methods

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  1. Psychological Investigations Formal Research Methods

  2. This session

  3. 3 Types of experiments….. • Laboratory experiment- these are conducted under highly controlled conditions to avoid extraneous or confounding variableseg: noise from effecting the results. • Strengths: Highly controlled variables + replicability. • Weaknesses: Artificial can lack realism + not relate to real world (low Ecological Validity) + higher chance of investigator bias + demand characteristics. • Watch ‘mythbusters experiment’

  4. 3 Types of Experiments Field experiments: these are conducted in the real world but the researcher still controls variables as much as possible. The Independent variable is still controlled with an expected Dependent variable. Strengths :Controlled variables in a natural environment + higher ecological validity, pps behave more naturally than in lab Weaknesses:but less control over extraneous variable; often time consuming; random allocation to conditions difficult.

  5. 3 Types of Experiments • Quasi (natural) experiments conducted in the real world but with less control over the IV and allowing the DV to naturally vary. Strengths: useful where it would be unethical/impossible to manipulate the IV; high levels of ecological validity. Weaknesses:We have no control over the independent variable; no random allocation to conditions.

  6. Glossary of Terms to add to your list!! • Demand characteristics: when pps try to please the experimenter or guess the aim of the study (SOCIAL DESIRABILITY BIAS) • Investigator Bias/ Hawthorne effect: When the experimenter biases the results by intervening verbally or non-verbally and influencing pps. • Pilot Test: This is a mini-run of the study to iron out methodological problems and allows procedural changes to be made before the ‘real’ experiment starts. NB: Watch video ‘Experimental method’

  7. SAMPLING- how are you going to find participants??? • There are many ways to interest the public to be pps. The most common ways are the following: • OPPORTUNITY SAMPLING- to find/ask whoever is available at the time. • A02- Quick / Cheap / Easy but not representative • RANDOM SAMPLING- picking out names from a hat or numbers randomly from a telephone directory. • A02- Expensive and time consuming but representative sample • SELF SELECTED/VOLUNTEER SAMPLING- the person them self shows interest in your research or they sign up to be a participant in your research. • AO2- Easy to get results. Demand characteristics and may not be representative of the whole population • There is also QUOTA sampling too. This means the population being investigated is divided up into categories. Eg: Investigating Maths ability at Purbeck School. This could be subdivided into year groups, ability groups, SEN, G+T ....... Then each category does the Maths test and the results are compared.

  8. Positive Correlation Negative Correlation Zero Correlation Correlation Coefficients +1.0 Perfect Positive +0.8 Strong +0.2 Weak 0 Zero - 0.2 Weak - 0.8 Strong - 1.0 Perfect Negative Correlation= the relationship between 2 variables

  9. Evaluation of correlations • Positives: 1. allows us to see how two variables relate to each other. 2.one can use one variable with many others to see the different relationships. • Eg: the number of ice cream sales tested with sunny/rainy weather, seasons, time of day • Weakness: 1.It is purely a description of relationships between variables. 2.It does not allow us to say one variable causes changes in another.3 there could be influences from a third variable

  10. VARIABLES IN RESEARCH HEAT NOISE

  11. OPERATIONALISATION- identifying the independent variable to be studied Psychologists are generally interested in what goes on in people’s minds. This presents them with a problem, because we can’t see what goes on in people’s minds. We can only see and measure their behaviour. This means that psychologists often have to work out ways of measuring mental processes (which can’t be seen) based on behavioural processes (which can). In technical terms psychologists use operational definitions of mental processes.

  12. What is an Aim? How is it different to a hypothesis? • An Aim is a reason given for the investigation in order to clarify the topic being studied. • A hypothesis is a prediction between two variables…….the independent variable and the dependent variable. • Complete the writing aims exercise in the booklet.

  13. Hypothesis- one/two tailed and null • Directional hypotheses predict the direction in which the results are expected to run (ONE TAILED) • eg:Eg:Taking regular exercise will decrease risk of heart disease • Non-directional hypotheses predict an effect of the IV on the DV, but not a direction (TWO TAILED) eg:There will be a significant difference between the amount of exercise taken and the chance of developing heart disease. • Null hypothesis states that any relationship or difference between the variables will just be down to chance…..eg:Any difference between the amount of exercise taken and the chance of developing heart disease is due to chance.

  14. Correlation – Hypotheses There will be a significant [direction] correlation between [variable 1] (measured by [something]) and [variable 2] (measured by [something]) There will be no significant correlation between [variable 1] (measured by [something]) and [variable 2] (measured by [something]) Alternative. Null

  15. Correlation – Hypotheses There will be a significant [direction] correlation between [variable 1] (measured by [something]) and [variable 2] (measured by [something]) There will be a significant correlation between [variable 1] (measured by [something]) and [variable 2] (measured by [something]) 1Tailed No Direction 2Tailed

  16. Experimental designs • Independent groups • Repeated measures • Matched pairs • Hitler hates qualitative data

  17. Independent Measures Participants are only in one condition. Experiments • Repeated Measures • The same participants repeat the two conditions Condition 1 Condition 2 Condition 1 Condition 2 Counter balancing – alter order of Pp’s

  18. Compare the results for the two groups Independent groups Recruit a group of participants Divide them into two This group does the experimental task with the IV set for condition 1 This group does the experimental task with the IV set for condition 2 Measure the DV for each group

  19. Compare the results for the two conditions Repeated measures Recruit a group of participants Condition 1 Condition 2 The group does the experimental task with the IV set for condition 1 The group repeats the experimental task with the IV set for condition 2

  20. Independent groups What sorts of problem are likely to arise from using two different groups of people? Problem: 1.The natural variation between the individuals (participant variables) in each group may affect the DV measurements. 2. Need a lot more pps. Control: After the PPs have been recruited, they should be randomly assigned to their groups. This should ensure the groups are similar, on average. Positives:easy to do as only 1 person at a time + no order effects (boredom, tiredness, practice)

  21. Repeated measures • What sorts of problem are likely to arise from using the same group of people twice? Control: Divide the PPs into two groups. Half does condition A first, then condition B. The rest do condition B then condition A. DV measurements for the conditions A and B are then compared (counterbalancing= ABBA effect Problem: Doing both conditions may (1) give PPs practice on the task; (2) make them bored or tired=Order effects; (3) allow them to work out the aim of the study=demand characteristics

  22. Experiments Matched Pairs – make two groups of participants as similar as possible. Condition 1 Condition 2 Male (Bob) 21 IQ = 105 Male (Richard) 21 IQ = 105 Female (Dawn) 25 IQ = 115 Female (Cara) 25 IQ = 115

  23. Compare the results for the matched pairs Matched participants Recruit a group of participants Find out what sorts of people you have in the group Recruit another group that matches them one for one Treat the experiment as independent measures Condition 1 Condition 2

  24. Matched pairs • What sorts of problem are likely to arise from using matched pairs of PPs? Problem: Several problems: (1) time consuming; (2) an exact match is rarely possible; (3) if one PP drops out you lose 2 PPs’ data. Positives:can carry out twin research and investigate specific behaviour. Control: Members of each pair should be randomly assigned to conditions. However, this does not solve all these problems.

  25. WALT….

  26. Evaluation of Experimental Designs

  27. Extension Task:Test your knowledge1.In groups read the studies and match up the correct IV/DV.

  28. Higher order thinking skills….. Now that you have identified the IV/DV for each study ....can you identify which study was: a)......a FIELD or LABORATORY EXPERIMENT. b) which study used..... INDEPENDENT MEASURES (1 pp=1 result) or REPEATED MEASURES (1pp=2+ results)

  29. Check you know:Variables in Experiments!! Independent variable- the variable being measured. Dependent variable-the result Extraneous Variables- variables that affect the experiment eg: participant /situational Participant Variables • Individual Differences- mood, gender, IQ Situational Variables • Any feature of the experiment that could influence a participants behavioureg: noise, heat, temperature

  30. Ethics in both Informal and Formal Research • Informed Consent • Deception • Right to Withdraw • Protection from harm • Confidentiality • Anonymity Teacher reminder:

  31. Activity- find the definitions that match with the ethical terms

  32. Gaining participants permission to take part in the studyafter being given detailed information about the research When participants are not told the true aims of the research and have not really given their informed consent

  33. Avoid or minimise mental or physical harm to participants. Keep results or participant’s personal information safe and not open to public access. Avoid using participant’s names or personal details. Offer participants the chance to leave the study at any time or if they feel uncomfortable with the procedures.

  34. What they mean?? • Informed Consent- gaining pps permission to take part in the study. • Deception- try not to deceive pps • Right to Withdraw- offer them the chance to leave the study at any time • Protection from harm- avoid mental or physical harm • Confidentiality – keep their results safe and not open to public access. • Anonymity- don’t use names or personal details

  35. Explain which ethics (+why) are important for the following types of research

  36. This session

  37. STARTER ACTIVITY: Identify the words in the anagrams. • EAVBRIAL • ETNEXRMIPE • SEHYPSTOHI • ESXOUTEARN

  38. Task: Match the key term with definition

  39. Key Words for your glossary!! • Standardised Instructions= written/verbal instructions said to pps explaining exactly what they will be doing in the study. • Debrief=explaining the aims of the research after the study including promising to keep the findings confidential but accessible by the pps at any time once the research has been completed.

  40. 12R/P WALT…..

  41. Reliability and Validity Reliability=CONSISTENCY • Questionnaires: Split-Half Method =re-ask questions in different order (ie: even numbers followed by odd numbers) • Interviews: Replicate them (Same as above) • Observation: Conduct an observation of behaviour using different observers (inter-observer reliability) Validity – ACCURACY • Interview: Ask OPEN questions – more valid • Observation- Improve by using wider categories or by asking participants – self-report • Questionnaire- make sure the questions relate to the topic being studied.

  42. With EXPERIMENTS…useTEST-RETEST….Validity is checked using the SAME participants to see if the second set of results were similar to the first. Reliability is done by repeating the procedure on a new set of pps to see if the results are consistent. BRAINS

  43. At last: Lets do some experiments!! • In groups work your way around all the different experiments or as many as you can!!. • Follow the instructions on the sheet. 2 students to collect results + 2 do experiment and then swap around. • Once you have collected your groups results move onto the next experiment. • Don’t forgot to write down what each experiment was about. Then in your groups choose ONE experiment and plan on the sheet provided.

  44. At last: Lets do some experiments!! • Experiment 1:An investigation into appearance and attraction • Experiment 2:An investigation into aggressive ratings of video games and films.

  45. Experiment 1: Instructions • Title: An investigation into appearance and attraction. • In front of you are cards with celebrities dressed in different styles (casual, smart, extreme). Your task is to rate each celeb from 1-5 (1=not attractive to 5=extremely attractive) based on their appearance. • Each of you must give a rating score. Work your way through all 3 boards (only male or only female depending upon your gender). Fill in the results table. NB: If your group are female only look at the male boards. If your group are male only look at the female boards. If your group are a mix of genders then can the boys rate the female boards and the girls rate the male boards. • Collect in your results.

  46. Experiment 2: Instructions • Title: An investigation into aggressive ratings of video games and films. • Task: Each person must separately rate the images sheets from 1=not violent to 10=very violent. • Record your scores in the results table provided.

  47. Results table- CASUALGirls rating male boards Boys rating female boards

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