1 Impression of Psychology With hopes of satisfying curiosity, many people listen to talk-radio counselors and psychics to learn about others and themselves. Dr. Crane (radio-shrink) Psychic (Ball gazing)

2 The Need for Psychological Science Intuition & Common Sense Many people believe that intuition and common sense are enough to bring forth answers regarding human nature. Intuition and common sense may aid queries, but they are not free of error.

3 Limits of Intuition Personal interviewers may rely too much on their “gut feelings” when meeting with job applicants. Taxi/ Getty Images

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  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

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

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

The Need for Psychological Science

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

The Need for Psychological Science  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

Description Case Study  Psychologists study one or more individuals in great depth in the hope of revealing things true of us all Is language uniquely human?

Description  Survey  technique for ascertaining the self-reported attitudes or behaviors of people  usually by questioning a representative, random sample of people  Random Sample  a sample that fairly represents a population because each member has an equal chance of inclusion

Description  False Consensus Effect  tendency to overestimate the extent to which others share our beliefs and behaviors  Population  all the cases in a group, from which samples may be drawn for a study

Description  If marbles of two colors are mixed well in the large jar, the fastest way to know their ratio is to blindly transfer a few into a smaller one and count them

Description

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

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

Scientific Approach to Behavior Experimental Research Descriptive/ Correlational Research Positive Correlation High scores on X are associated with high scores on Y, and low scores on X are associated with low scores on Y. # of Cigarettes Smoked X Blood Pressure Reading Y # of Cigarettes Smoked X Blood Pressure Reading Y Ethics Statistics and Research Evaluating Research

Negative Correlation High scores on X are associated with low scores on Y, and low scores on X are associated with high scores on Y. Amount of Cocaine Ingested X # of Hours Slept Y Amount of Cocaine Ingested X # of Hours Slept Y Scientific Approach to Behavior Experimental Research Descriptive/ Correlational Research Ethics Statistics and Research Evaluating Research

Negative CorrelationPositive Correlation Strength of Relationship Increasing HighModerateLowHighModerateLow Scientific Approach to Behavior Experimental Research Descriptive/ Correlational Research Ethics Statistics and Research Evaluating Research

Scientific Approach to Behavior Experimental Research Descriptive/ Correlational Research Ethics Statistics and Research Evaluating Research.05 level of significance

Correlation Height and Temperament of 20 Men Subject Height in Inches Temperament Subject Height in Inches Temperament

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

Illusory Correlation  Illusory Correlation  the perception of a relationship where none exists ConceiveDo not conceive Adopt Do not adopt disconfirming evidence confirming evidence disconfirming evidence confirming evidence

Two Random Sequences  Your chances of being dealt either of these hands is precisely the same: 1 in 2,598,960.

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

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

Statistical Reasoning Our Brand Brand Brand Brand X Y Z 100% Percentage still functioning after 10 years Brand of truck

Statistical Reasoning Our Brand Brand Brand Brand X Y Z 100% Percentage still functioning after 10 years Brand of truck

Statistical Reasoning  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 A Skewed Distribution Mode Median Mean One Family Income per family in thousands of dollars

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?

Frequently Asked Questions about Psychology Is psychology potentially dangerous?

1 Psychology is Empirical 2 Psychology is Theoretically Diverse 3 Psychology Evolves in a Sociohistorical Context Psychology Today: Vigorous and Diversified Seven Unifying Themes Personal Application Psychology’s Early History Psychology’s Modern History

4 Behavior is Determined by Multiple Causes 5 Behavior is Shaped by Cultural Heritage 6 Heredity and Environment Jointly Influence Behavior 7 People’s Experience of the World is Highly Subjective Psychology Today: Vigorous and Diversified Seven Unifying Themes Personal Application Psychology’s Early History Psychology’s Modern History