That’s Not True!!!! Research Methods in Psychology

Cause and effect –With an experiment, we can determine cause and effect because we are systematically manipulating variables –Hypothesis-what do we think will happen in the study? –Independent variable(s): –Dependent variable(s):

Operational definitions- –What do you mean by the I.V.? –What do you mean by the D.V.? –You need to define them so people who read your study know what you are talking about

Subjects: –Population –Sample - #s –Random Assignment –Experimental Group –Control Group

Extraneous vs. Confounding variables –Extraneous – –Confounding –

Flaws to look for 1. Internal –The problem with internal validity is that it becomes very difficult to generalize the results to the rest of the population. (This can also be a problem with case studies). 2. External validity-

3. Sampling bias - You need to draw a large enough sample to represent the population under study and then utilize random sampling

4. Placebo effects – Simply placing something in one’s mouth may cause one to experience a placebo effect Placebo effects can ruin the experiment because you cannot tell if the drug actually had an effect on the subject or not.

5. Distortion of self-report-Occurs when interview and surveys are given. The subject may lie in giving their answers (or just stretch the truth). Can happen in one of two ways: A. Social desirability- B. Response set- (Ex- when people agree with or disagree with everything on the survey. Most surveys are set up to elicit positive/negative answers or so that different choices should be made.

6. Experimenter bias - The best way to overcome this is to do a double-blind study, in which the experimenter does not know which subjects are in which groups

Developmental Studies In order to study development of human beings, we use several different designs: –1. Cross-sectional –2. Longitudinal –3. Sequential

Pros and cons with Research Methods 1. Naturalistic Observation –Pros – –Cons –

2. Laboratory Experiment –Pros – –Cons –

3. Surveys –Pros – –Cons –

4. Interviews –Pros – –Cons –

5. Case Study –Pros – –Cons –

Ethical Issues in Psychology 1. Subject participation – voluntary –Should not be forced or feel pressured –Should be informed of any factor of research that might make them decide not to participate –Should be allowed to end participation at any time and still get paid (if they are getting paid)

2. Subjects are not to be harmed in any way –Protect from psychological and physical harm –Studies that may only effect one’s emotions in a slight way are acceptable

3. Deception of participants – Is it okay? –Should be done to inform participants –Debriefing of subject is usually necessary

4. Right to privacy should not be violated –Don’t give out information on your subjects –If data regarding subjects will be released, subjects must be informed and consent must be obtained

5. Can we cause them harm? –Yes to animals – but you must be able to justify it –Animals should be maintained in a manner that is considered decent treatment

6. Approval must be obtained from the institution that the researcher works for –Research must be reported in an ethical fashion –Research should be reported as soon as possible for verification

Measures of Central Tendency Mean-Average of all the data Mode-# that appears most often. You may have a bimodal distribution which means that two #’s appear the same # of times and are the most frequent #’s in the data set. Median-# in the middle Range – subtract the lowest # from the highest #

Correlational Studies While experiments tell us about cause and effect, –correlational studies do NOT tell about causation –they ONLY tell us if there is a relationship Usually after the fact Often cannot experiment on humans Follow-up may be experiment with animals

Correlational Research Look for: –Positive vs. negative relationships –Strength of the number

Correlational Research +1 – – – – 0 –