Class Starter # 5 zWhat are the 3 types of research done by psychologists?

Myers’ PSYCHOLOGY (7th Ed) Chapter 1 Thinking Critically with Psychological Science

The Need for Psychological Science Psychologists, like all scientists, use the scientific method to construct theories that organize observations and imply testable hypotheses

The Need for Psychological Science

3 Broad Categories of Research z1) Experiments based on scientific method; “cause and effect” z2) Descriptive studies-case studies, surveys, & naturalistic observation z3) Correlation studies-look for a relationship between variables

The Need for Psychological Science  Theory  an explanation using an integrated set of principles that organizes and predicts observations  Hypothesis  a testable prediction  often implied by a theory

Experimentation  Experiment  an investigator manipulates one or more factors (independent variables) to observe their effect on some behavior or mental process (the dependent variable)  by random assignment of participants the experiment controls other relevant factors

Experimentation  Operational Definition  a statement of procedures (operations) used to define research variables  Example-  intelligence may be operationally defined as what an intelligence test measures

Experimentation  Independent Variable  the experimental factor that is manipulated  the variable whose effect is being studied  Dependent Variable  the experimental factor that may change in response to manipulations of the independent variable  in psychology it is usually a behavior or mental process

Experimentation  Random Assignment  assigning participants to experimental and control conditions by chance  minimizes pre-existing differences between those assigned to the different groups

Experimentation  Placebo  an inert substance or condition that may be administered instead of a presumed active agent, such as a drug, to see if it triggers the effects believed to characterize the active agent  Double-blind Procedure  both the research participants and the research staff are ignorant (blind) about whether the research participants have received the treatment or a placebo  commonly used in drug-evaluation studies

Experimentation  Experimental Condition  the condition of an experiment that exposes participants to the treatment, that is, to one version of the independent variable  Control Condition  the condition of an experiment that contrasts with the experimental treatment  serves as a comparison for evaluating the effect of the treatment

Experimentation  Replication  repeating the essence of a research study to see whether the basic finding generalizes to other participants and circumstances  usually with different participants in different situations

Description Psychologists describe behavior using case studies, surveys, and naturalistic observation

Case Study  Psychologists study one or more individuals in great depth in the hope of revealing things true of us all Ex. case study of Phineas Gage, railroad worker who was stabbed through the brain with a metal shaft.

Surveys  technique for ascertaining the self-reported attitudes or behaviors of people  usually by questioning a representative, random sample of people

Naturalistic Observation  observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation

The Need for Psychological Science  Critical Thinking  thinking that does not blindly accept arguments and conclusions  examines assumptions  discerns hidden values  evaluates evidence

Terms  Hindsight Bias  we tend to believe, after learning an outcome, that we would have foreseen it  the “I-knew-it-all-along” phenomenon  Overconfidence  we tend to think we know more than we do

Terms  False Consensus Effect  tendency to overestimate the extent to which others share our beliefs and behaviors zExample Romantic relationships between people often start off with a glow as hormones and False Consensus overshadow real differences. However, the cloud-9 effect eventually wears off as the loving couple eventually discover that they are not, after all, that similar (and in fact often are amazingly incompatible!).

Terms  Illusory Correlation  the perception of a relationship where none exists

Correlation  Correlation Coefficient  a statistical measure of the extent to which two factors vary together, and thus how well either factor predicts the other Correlation coefficient Indicates direction of relationship (positive or negative) Indicates strength of relationship (0.00 to 1.00) r = +.37

Correlation  Scatterplot  a graphed cluster of dots, each of which represents the values of two variables  the slope of the points suggests the direction of the relationship  the amount of scatter suggests the strength of the correlation  little scatter indicates high correlation  also called a scattergram or scatter diagram

Correlation Perfect positive correlation (+1.00) No relationship (0.00)Perfect negative correlation (-1.00) Scatterplots, showing patterns of correlations

Correlation Scatterplot of Height and Temperament Temperament scores Height in inches

Correlation Three Possible Cause-Effect Relationships (1) Low self-esteem Depression (2) Depression Low self-esteem Depression (3) Distressing events or biological predisposition could cause or and

Comparing Research Methods

Statistics  Mode  the most frequently occurring score in a distribution  Mean  the arithmetic average of a distribution  obtained by adding the scores and then dividing by the number of scores  Median  the middle score in a distribution  half the scores are above it and half are below it

Statistical Reasoning  Range  the difference between the highest and lowest scores in a distribution  Standard Deviation  a computed measure of how much scores vary around the mean  Statistical Significance  a statistical statement of how likely it is that an obtained result occurred by chance

Frequently Asked Questions about Psychology Can laboratory experiments illuminate everyday life?

Frequently Asked Questions about Psychology Does behavior depend on ones culture?  Culture--the enduring behaviors, ideas, attitudes, and traditions shared by a large group of people and transmitted from one generation to the next

Frequently Asked Questions about Psychology Does behavior vary with gender?

Frequently Asked Questions about Psychology Why do psychologists study animals? Is it ethical to experiment on animals? Is it ethical to experiment on people?

Frequently Asked Questions about Psychology Is psychology free of value judgments?