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Research Strategies: How Psychologists Ask and Answer Questions Module 3. Research Strategies: How Psychologists Ask and Answer Questions. Description The Case Study The Survey Naturalistic Observation Correlation Correlation and Causation Illusory Correlation
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Research Strategies: How Psychologists Ask and Answer QuestionsModule 3
Research Strategies: How Psychologists Ask and Answer Questions Description • The Case Study • The Survey • Naturalistic Observation Correlation • Correlation and Causation • Illusory Correlation • Perceiving Order in Random Events
Research Strategies: How Psychologists Ask and Answer Questions Experimentation • Exploring Cause and Effect • Evaluating Therapies • Independent and Dependent Variables Statistical Reasoning • Describing Data • Making Inferences
Descriptive Methods A technique in which one person is studied in depth to reveal underlying behavioral principles. Case Study Is language uniquely human? • Advantage: tremendous amount of detail. • Disadvantage: cannot apply to others. • Famous case study: Phineas Gage
Survey A technique for ascertaining the self-reported attitudes, opinions or behaviors of people usually by questioning a representative, random sample of people. http://www.lynnefeatherstone.org
Survey Wording Effect Wording can change the results of a survey. Q: Should cigarette ads and pornography be allowed on television? (not allowed vs. forbid)
Survey False Consensus Effect A tendency to overestimate the extent to which others share our beliefs and behaviors.
Survey Population – all the cases in a group From a population, if each member has an equal chance of inclusion into a sample, we call that a random sample (unbiased). Random Sampling The fastest way to know about the marble color ratio is to blindly transfer a few into a smaller jar and count them.
LO 1.9 Case studies and surveys Random Sampling from Population INFERENCE POPULATION SAMPLE
Naturalistic and laboratory settings Descriptive Methods • Naturalistic observation – watching animals or humans behave in their normal environment. • Major Advantage: • Realistic picture of behavior. • Disadvantages: • Observer effect - tendency of people or animals to behave differently from normal when they know they are being observed. • Participant observation - a naturalistic observation in which the observer becomes a participant in the group being observed (to reduce observer effect).
Naturalistic and laboratory settings Descriptive Methods • Laboratory observation – watching animals or humans behave in a laboratory setting. • Advantages: • Control over environment. • Allows use of specialized equipment. • Disadvantage: • Artificial situation that may result in artificial behavior. • Descriptive methods lead to the formation of testable hypotheses. Menu
Indicates direction of relationship (positive or negative) Correlation coefficient Indicates strength of relationship (0.00 to 1.00) Correlation When one trait or behavior accompanies another, we say the two correlate. Correlation Coefficient is a statistical measure of relationship between two variables. r = + 0.37
Finding Relationships Correlational technique • Correlation coefficient ranges from 0 to 1.00 • Closer to 1.00, the stronger the relationship between the variables. • No correlation = 0.0. • Perfect correlation = -1.00 OR +1.00. • Positive correlation – variables are related in the same direction. • As one increases, the other increases; as one decreases, the other decreases. • Negative correlation – variables are related in opposite direction. • As one increases, the other decreases. • CORRELATION DOES NOT PROVE CAUSATION!!! Menu
Scatterplots Perfect positive correlation (+1.00) Scatterplotis a graph comprised of points generated by values of two variables.
Scatterplots Perfect negative correlation (-1.00) No relationship (0.00) Scatterplot on the left shows a negative correlation, and the one on the right shows no relationship between the two variables.
Data Data showing height and temperament in people.
Scatterplot Scatterplot showing relationship between height and temperament in people with a moderate positive correlation of +0.63.
LO 1.10 Correlational technique Correlation does NOT prove causation Menu
Do not conceive Conceive Adopt Confirming evidence Disconfirming evidence Do not adopt Disconfirming evidence Confirming evidence Illusory Correlation The perception of a relationship where none exists. Parents conceive children after adoption. Michael Newman Jr./ Photo Edit
Order in Random Events Given large number of random outcomes, a few are likely to express order. Jerry Telfer/ San Francisco Chronicle Angelo and Maria Gallina won two California lottery games on the same day.
Experimentation Exploring Cause and Effect The backbone of research in psychology. Experiments isolate causes and their effects.
Exploring Cause & Effect Many factors influence our behavior. Experiments (1)manipulate factors that interest us while keeping other factors under (2) control. Effects generated by manipulated factors isolate cause and effect relationships.
Experimental approach and terms The Experiment • Operational definition - definition of a variable of interest that allows it to be directly measured. • Independent variable (IV) - variable in an experiment that is manipulated by the experimenter. • Dependent variable (DV) - variable in an experiment that represents the measurable response or behavior of the subjects in the experiment. Definition: Aggressive play IV: Violent TV DV: Aggressive play
For example, to study the effect of breast feeding on intelligence. Breast feeding is the independent variable. For example, the effect of breast feeding on intelligence - intelligence is the dependent variable.
Evaluating Therapies Double-blind Procedure In evaluating drug therapies it is important to keep the patients and experimenter’s assistants blind to which patients got real treatment and which placebo.
Evaluating Therapies Random Assignment Assigning participants to experimental (Breast-fed) and control (formula-fed) conditions by random assignment minimizes pre-existing differences between the two groups.
LO 1.11 Experimental approach and terms Random Assignment Experimental Group Test for Differences SAMPLE Control Group Menu
LO 1.11 Experimental approach and terms Confounding Variables Effect of violent tv on aggression Experimental Group SAMPLE Are differences due to manipulation or confounding variable (mood)? Control Group Menu
LO 1.11 Experimental approach and terms No Confounding Variables Effect of violent tv on aggression Experimental Group SAMPLE Differences due to manipulation, not an extraneous variable because mood randomly determined. Control Group Menu
LO 1.11 Experimental approach and terms The Experiment Menu
Experimentation A summary of steps during experimentation.
Comparison Below is a comparison of different research methods.