Investigations

Investigations

1. Self Reports

   • (feelings, attitudes, beliefs0
   • Questionnaires
     • set of questions in a highly structured written form. (open or closed)
     • set of questions written in a highly structured written form (open or closed)
     • Strengths
       • - study large samples of people fairly easy and quickly, able to examine large number of variables. allows pts to reveal behaviour and feelings experienced in real life.
     • Weaknesses
       • - not respond truthfully, produce socially desirability bias, portray themselves in a good light - often leading q's, force pts to give a particular reply. questions are not always clear, unaware if pts has really understood question (invalid data)
   • Interviews
     • spoken questionnaire, record respondants replies.  can be structured with predetermined questions or unstructured with no predicted questions.  or semi structured with both pre determined questions and further questions allowing respondants to expand upon their replies.
     • Strengths
       • - in depth qualitative data, allows pts to describe their own experiences and feelings in more detail.
     • Weaknesses
       • - unstructured interviews can be very time consuming and very difficult to carry out. - structured interviews can restrict respondats replies.
   • Open/closed questions
     • open - allows participants to display their own feelings and adapt to their response. closed- simple yes or no answer
     • Strengths
       • Closed questions - produce simple quantitative data which is easy to analyse statistically open questions - allow respondants to produce in depth responses relating to what pts actually thinks, in depth qualitative data
     • Weaknesses
       • closed questions - restricted by categories, do not allow respondants to give in depth insights.
   • Rating scales
     • how strongly they agree or disagree with a statement. (strongly agree/agree/undecided/disagree/strongly disagree)
     • Strengths
       • - gives an idea of how strongly pts feel about something. gives more detail than a simple yes or no answer. - data is quantitative, easy to analyse statistically.
     • Weaknesses
       • - ptsoften choose middle range answers to prevent them from looking so extreme. - data is quantitative so does not give in depth replies. pts forces to choose from minimal choices.
   • Fixed choice questions
     • pts only have the option to choose yes or no.
     • Strengths
       •  - easy to measure and quantify and pts cannot opt fot middle range answers only.
     • Weaknesses
       • pts may not feel their are many options to choose from and desired response is not available. also the issue of not having in depth qualitative data.
   • Reliability
     • measurement is reliable if it produces similar results if the measurement is repeated again in similar circumstances. questionnaires/psychometric tests can measure reliability through split half methods. split test into two halves and pts completing both halves. if both halved produce similar results, internally reliable. improve reliability through explaining ambiguous questions and interviewers can be given training.
   • Validity
     • refers to if a study measures what it is supposed to measure. questionnaires often lack validity, pts may lie and qualitative data is better than quantitative data. assess through concurrent validity, compare results from a self report method to another self report method on the SAME topic. improve validity - leading questions avoided, open questions added which allows respondants to expand upon their replies. also, confidentiality can be reinforced to gain more truthful responses.
   • Sampling
     • Oppertunity Sampling
       • taking sample who are available at that given time
       • Strengths
         • - quick and easy in terms of time and money, can use friends, family or collegues.  seen as adequate when investigating processes which are thought to work in similar ways for most individuals such as memory processes. - can control who is being studied. particularly useful with natural experiments.
       • Weaknesses
         • produce a biased sample, researchers may choose pts from the same cultural and social group. not representative of the target population as friends have different qualities compared to general population. - pts maay decline to take part, producing an even more biased sample as those pts responding may be particular type of person
     • Self Selected
       • Pts volunteer, or respond to an advertisement or request
       • Strengths
         • relatively quick and easy to carry out, can reach a wide variety of pts.
       • Weaknesses
         • may not be representative of the target population. type of people who respond to adverts may be more obedient, and more motivated to take part in studies.
     • Random
       • taking sample from target population, everyone has an equal chance of being selected
       • Strengths
         • best technique for achieving an unbiased sample, easier to generalise to the target population
       • Weaknesses
         • time consuming and impossible to carry out if there is a large target population. sample is already not random because you usually have people volunteering and similarly if you advertise, impossible to ensure that every member of target population views the advert.