1. Research in Psychology Chapter Two
AP Psychology

2. Thinking Critically About Psychology
What am I being asked to believe or accept?
What evidence is available to support the assertion?
Are there alternative ways of interpreting the evidence?
What additional evidence would help to evaluate the alternatives?
What conclusions are most reasonable?

3. Reliability and Validity Evidence addressing a hypothesis should be judged in terms of reliability and validity.

4. Theories
A theory is an integrated set of statements designed to account for and predict ways of controlling certain phenomena.
They are tentative explanations that must be subjected to scientific evaluation.
They are constantly being formulated, evaluated, reformulated, and sometimes abandoned based on research results.

5. Goals of Psychological Research
To describe the phenomenon
To make accurate predictions
To demonstrate some control over the variables
To explain the phenomenon with confidence

6. Research Methods in Psychology

7. Naturalistic Observation
Feature: The process of watching without interfering as behavior occurs in the natural environment
Strengths: Provides descriptive data about behavior presumably uncontaminated by outside influences.
Pitfalls: Observer bias and participant self-consciousness can distort results

8. Case Studies
Feature: Intensive examination of the behavior and mental processes associated with a specific person, group or situation.
Strengths: Provide detailed descriptive analysis of new, complex, or rare phenomenon.
Pitfalls: May not provide representative picture of phenomena.

9. Surveys
Feature: Standard set of questions asked of a large number of participants – asks people about their behavior, attitudes, beliefs, and opinions
Strengths: Gather large amounts of descriptive data relatively quickly and inexpensively.
Pitfalls: Sampling errors, poorly phrased questions, and response biases can distort results.

10. Correlational Studies
Feature: Examine the relationships between research variables.
Strengths: Can test predictions, evaluate theories, and suggest new hypotheses.
Pitfalls: Cannot infer causal relationships between variables.

11. Correlation
Correlation – the degree to which one variable is related to another

12. Correlation Coefficients
Correlation Coefficient – a statistic, r, that summarizes the strength and direction of a relationship between two variables
Indicates direction
of relationship
(positive or negative)
Correlation
coefficient
r = +.37
Indicates strength
of relationship
(0.00 to 1.00)
Strong Correlation
Moderate Correlation
Weak Correlation

13. Illusory Correlation
The perception of a relationship where none exists
Misinterpretation of random sequences

14. Experiments
Feature: Manipulation of an independent variable and measurement of its effects on a dependent variable.
Strengths: Can establish a cause-effect relationship between independent and dependent variables.
Pitfalls: Confounding variables may prevent valid conclusions.

15. Key Terms Hypothesis Independent Variable Dependent Variable
Operational Definition
Experimental Group
Control Group
Confounding Variables
Random Variables
Participant Expectations
Placebo
Confirmation Bias

16. Figure 2.1: A Simple Two-Group Experiment
Independent Variable: Whether or not one received the EMDR treatment.
Dependent Variable: Anxiety level.

17. Sources for Confounding Variables
Random Variables
Importance of random assignment
Participants’ Expectations
Placebo effect
Experimenter Bias
Often minimized through the use of a double-blind design

18. Research
Basic research- describe and understand behavior without immediate concern for practical use.
Applied research- scientific studies to solve problems of everyday life.

19. Selecting Human Participants for Research
The sampling procedures used can:
Affect the research results.
Limit the meaning of the results
Sampling – the process of selecting participants for research

20. Representative Samples
A group of research participants whose characteristics fairly reflect the characteristics of the population from which they were selected
If psychologists want to make scientific statements about the behavior and mental processes of any large group, they must use a representative sample of participants

21. Random vs. Biased Samples
Random - A group of research participants selected from a population whose members all had an equal chance of being chosen
Biased – A group of research participants selected who did not have an equal chance of being chosen

22. Convenience Samples
Populations that are conveniently available to the researcher
Researcher must check age, gender, ethnicity, and other characteristics of participants

23. Statistical Analysis of Research Results
Descriptive Statistics - #s that describe a set of research data
Measures of Central Tendency
Measures of Variability
Correlation Coefficients
Inferential Statistics – a set of mathematical procedures that help researchers infer what their data mean

24. Cross-Sectional Research
A study of various ages at one point in time.
Positives: can gather information about the effect in each age group

25. Ethics Ethical considerations:
Reviewed by a board in academic institutions
Codes put out by APA
Obtain informed consent from all subjects
Protect subjects from harm and discomfort
Treat all data confidentially
Explain the experiment and results to subjects afterward.

26. Animal Care
Reviewed by a committee IACUC (institutional animal care and use committee)
Will periodically visit animal colonies to ensure proper care

27. Measures of Central Tendency
Mean – average
Median – halfway point
Mode – occurs most frequently

28. Measures of Variability
Range – difference between highest and lowest values
Standard Deviation (SD) – average distance between each score and the mean of the data set

29. Table 2.4: A Set of Pretreatment Anxiety Ratings

30. Citations
Psychology, Seventh Edition