Download - Research Issues
Research Issues
Research IssuesEcological Validity – degree of
which behaviour observed in study reflects everyday life. Takes into consideration:
◦Generalisability – the extent to which the findings can be generalised.
◦Representativeness (mundane realism) – The extent to which the study mirrors real life.
TaskConsider some of the following
experiments that we have already studied. Write down whether you think they are high or low in ecological validity (consider both generalisability and representativeness) and give reasons to justify your answer.◦ Milgram’s 1963 study of obedience.◦ Hofling et al, 1966 Nurses Study◦ Rank and Jacobsen, 1977 Australian Nurses
study.◦ Mandel, 1998 Police Battalion 101.
Descriptive StatisticsMeasures of Central TendencyMeasures of DispersionVisual Display
Research IssuesEcological Validity – degree of
which behaviour observed in study reflects everyday life. Takes into consideration:
◦Generalisability – the extent to which the findings can be generalised.
◦Representativeness (mundane realism) – The extent to which the study mirrors real life.
TaskConsider some of the following
experiments that we have already studied. Write down whether you think they are high or low in ecological validity (consider both generalisability and representativeness) and give reasons to justify your answer.◦ Milgram’s 1963 study of obedience.◦ Hofling et al, 1966 Nurses Study◦ Rank and Jacobsen, 1977 Australian Nurses
study.◦ Mandel, 1998 Police Battalion 101.
Descriptive StatisticsMeasures of Central TendencyMeasures of DispersionVisual Display
Measures of Central TendencyFinding the average of raw data
using mean, median or mode.Mean – average (adding and
dividing by n)Median – middle value in ordered
listMode – most common
TaskThe class will be divided in to 5 groups.
Each group needs to find the mean, median and mode of their topic.
1. No. of coloured paper clips.2. No. of coloured pins.3. No. of SG passes at Credit level.4. No. of hours slept last night.5. No. of siblings (including step and half
siblings). You must design this task yourself and
decide what is the best way to collect the data etc.
EvaluationMean – makes use of all data
collected but it can be misleading if there are extremes.
Median – not affected by extreme scores but not al scores are taken into account.
Mode – useful when in categories (ie coloured pins)
Measures of DispersionAnother way to describe the statistics is to
show how spread out the numbers are.
Range - difference between the highest number and the lowest. A set of numbers can have the same mean but a different range.
Find the range from yesterday’s tasks.Standard Deviation – requires a
mathematical calculator. Measures the spread of the data around the mean.
Visual DisplayEasy and quick way to interpret
results.Use your data from yesterday’s
task to create a bar chart which simply displays your relevant results.
Remember to label the x and y axis.
Quantitative and Qualitative Data
Quantitative Data – Numbers, raw scores, percentages, means (descriptive data)◦ Easier to analyse◦ Simplifies human behaviour
Qualitative Data – descriptions, words, pictures, meanings (interviews)◦ Represents the complexity of human
behaviour.◦ More difficult to analyse
SamplingWhen choosing participants
experimenters must choose a selection of the population which are representative of the target population. Types of sampling are:◦Opportunity◦Volunteer◦Random◦Systematic
Sampling
Opportunity - asking people off the street.◦Anyone who is available.
Inevitably biased
Volunteer – adverts ◦Offers access to variety of
participants. Volunteer bias – more highly motivated
SamplingRandom – Randomly select
participants from the complete list of target population.◦Unbiased
Impossible to obtain complete list.Systematic – selecting every nth
member of the target population list.◦Often mistaken for random sampling –
random means taken from a hat/picked from a list without a systematic approach.
Ethical IssuesFinding a balance between the aims
of the experiment and the rights and wellbeing of the participants.
Issues to be considered are:◦Deception◦Informed consent◦The right to withdraw◦Protection from harm◦Confidentiality◦Privacy
DeceptionSometimes necessary to secure more
accurate behaviour.However – deception is unethical, it may
stop participants from giving informed consent (as they are not fully informed) and leads people to believe that psychologists are untrustworthy (not take part in an experiment again)
Ethical committee should approve such deception after weighing up pros and cons (subjective).
Debriefing (participants may still feel embarrassed).
Informed ConsentReveals true aim of the study and may
make results invalid.Participants need this information in
order to know whether they want to take part.
Presumptive consent – asking a group of similar people to the participants if they would agree to take part in the study – if they say yes you can presume that the participants would also agree (what people say and do are very different things).
Protection from physical and psychological harmSome of the bigger psychological
issues involve participant distress.
No harm (physical or psychological) should come to any participants and any risk of harm should be no greater than in the real world.
Difficult to predict the outcome of experiments eh Zimbardo’s Prison Experiment.
The Right to WithdrawMore difficult in observational field
experiments (Piliavin’s Altruism on a train study)
Everyone should have the option to quit, even with informed consent people may not be fully aware of what is going to happen.
Participants may not withdraw even if they want to through a feeling of obligation.
ConfidentialityIf findings are published it may
be difficult to promise complete confidentiality despite anonymity (St Helena), as some details may lead to participants being recognised.
Data Protection Act – confidentiality is a legal right.
Researchers shouldn’t record names.
PrivacyDifficult in field experiments.
(Middlemist et al, 1976, Pee study)
Everyone has a right to privacy.People should not be observed
without informed consent unless it is in a public place (what is a public place?)
Give retrospective consent and allowed to withhold data. (still acceptable? Someone has just watched you pee!)
Ethics Governing BodiesBritish Psychological Society
(BPS) and American Psychological Association (APA).
These bodies develop ethical guidelines (see handout) so as they are aware of what is acceptable and how to overcome any ethical issues.
Does this absolve the experimenter of responsibility?