Psychology & Science Three research strategies for scientific investigation: • Survey • Case study • Experiment Survey The survey technique involves the collection of primary data about subjects, usually by selecting a representative sample of the population or universe under study, through the use of a questionnaire. It is a very popular since many different types of information can be collected, including attitudinal, motivational, behavioral & perceptive aspects. Disadvantages: How questions are worded & who asks the questions can cause errors. Advantages: quick & easy collection of information & gives the ability to identify problems & evaluate treatment programs. Case Study A Personal case study, is a.k.a. a testimonial. Disadvantages: Only applies to one individual & a great potential for error & bias can occur from; • the personal beliefs of the person doing the study. • a self fulfilling prophecy involves having a strong belief or making a statement about a future behavior & then acting, usually unknowingly to fulfill or carry out the behavior. Advantages: may provide detailed information that allows greater understanding of a particular person's life. Case studies can point the way to other research solutions. Experiment An experiment is a method for identifying cause & effect relationships by following a set of rules & guidelines that minimize the possibility of error, bias & chance occurrences. • Disadvantage: Information obtained in one experimental situation or laboratory situation may not apply in other situations. • Advantage: Identifies cause & effect. Conducting an experiment: seven rules: - Rule 1: ask (hypothesis) - Rule 2: identify variables - Independent variable (treatment) - Dependent variable (resulting behavior) - Rule 3: choose subjects (random selection) - Rule 4: assign subjects randomly - Experimental group - Control group - Rule 5: manipulate independent variable - administer treatment - Use double-blind procedure - Rule 6: measure resulting behavior (dependent variable) - Rule 7: analyze data Placebos A placebo, from the Latin for "I will please", is a medical treatment (operation, therapy, chemical solution, pill, etc.), which is administered as if it were a therapy, but which has no therapeutic value other than the placebo effect. The "placebo effect" is the phenomenon that a patient's symptoms can be alleviated by an otherwise ineffective treatment, since the individual expects or believes that it will work. Common world-wide placebos include Rhino horn, Bear gallbladders, Tiger bones & Magnets. Testimonials (which are a subset of case studies) support the use of placebos. Decisions about Doing Research Research techniques: • Interview & questionnaire • Standardized test • Laboratory experiment • Animal model Research settings: - Naturalistic setting (case study), unique to one individual; but, may provide information that cannot be obtained in any other way. - Laboratory setting, results may not transfer to "real" life; but, the controlled setting reduces errors or bias. Correlation A correlation is an association / relationship between the occurrence of two or more events, a correlation coefficient is a signed number signifying the strength & direction of that relationship. Perfect positive correlation coefficient (+1.00) (always) Positive correlation coefficient (+0.01 to +0.99) (sometimes happens) Zero correlation (0.00) (events happen at random) Negative correlation coefficient (-0.01 to -0.99) (sometimes) Perfect negative correlation coefficient (-1.00) (Never) Correlations are positive if the occurrence of the events in each domain increase together. Correlations are negative if the occurrence of the events in one domain increases as the occurrence of events in the other domain decreases. Correlation is not causation! it is a clue that can be used to predict. Study Questions: 1. How believable is a recent survey that reported that people never lie to their best friends? 2. Why do some people put more faith in testimonials than in proven research? 3. How would you explain the positive correlation (0.60) researchers found between drinking coffee and being sexually active after age 60? 4. How would you determine whether taking vitamin B reduces stress? 5. If you has a child who might have ADHD, what would you do? 6. What concerns might a student have about volunteering to be a subject in an experiment? --------------------------------- Topics in Psychology Robert C. Gates