Designing Psychological Investigations
Questionnaires – face-to-face, on the phone, or via the internet.
Questionnaires are a self-report method. Self-report methods involve asking participants about their feelings, beliefs and attitudes etc.
Advantages – Practical – can collect a large amount of information quickly and relatively cheaply.
Disadvantages – Bad questions – leading questions (questions that suggest a desired answer) or unclear questions can be a problem.
Biased samples – some people are more likely to respond to a questionnaire, which might make the sample unrepresentative.
Social desirability bias – people sometimes want to present themselves in a good light. What they say and what they actually think could be different, making any results unreliable.
Ethics – confidentiality can be a problem, especially around sensitive issues which people might not want to discuss.
Other self-report methods include interviews and case studies. Self-report methods provide rich, qualitative data.
Correlational Research Looks for Relationships between Variables
Correlation means that two variables appear to be connected – they rise and fall together, or one rises as the other falls. But it doesn’t always mean that one variable causes a change in the other, e.g. as age increases so might stress, but age doesn’t cause stress.
Advantages – Causal relationships – these can be ruled out if no correlation exists.
Ethics – can study variables that would be unethical to manipulate. E.g. is there a relationship between the number of cigarettes smoked and incidences of ill health?
Disadvantages – Causal relationships – these cannot be assumed from a correlation, which may be caused by a third, unknown variable. Sometimes the media (and researchers) infer causality from a correlation.
Experiments can be done in a laboratory or in the natural environment
Laboratory experiments are…