Psychology’s Roots, Big Ideas, and Critical Thinking Tools Chapter 1

How Do Psychologists Ask and Answer Questions? The Scientific Method Description Correlation Experimentation Biopsychosocial events – our biology our psychological makeup and our environment all contribute to our behavior.

Behavior is a Biopsychosocial Event: Nature v. Nurture Nature-nurture issue: The longstanding controversy over the relative contributions that genes and experience make to the development of psychological traits and behaviors. Today, we see traits and behaviors arising from the interaction of nature and nurture Question: How are differences in intelligence, personality and psychological disorders influenced by heredity and by environment?

Why Do Psychology? The Limits of Intuition and Common Sense The Scientific Attitude Can we rely on just our intuition? Does it steer us wrong sometimes?

The Limitations of Intuition and Common Sense Intuitions and hunches are a good place to start, but must be followed up by critical thinking “The first principle is that you must not fool yourself – and you are the easiest person to fool.” – Richard Feynman

Hindsight Bias or the “I-knew-it-all-along” phenomenon. The tendency to believe, after learning an outcome, that we could have predicted it. “Anything seems commonplace, once explained.” Dr. Watson to Sherlock Holmes. Two phenomena – hindsight bias and judgmental overconfidence – illustrate why we cannot rely solely on intuition and common sense. Do exercise with solving letter scramble now.

Overconfidence Sometimes we think we know more than we actually know. Anagram How long do you think it would take to unscramble these anagrams? WREAT WATER ETYRN ENTRY People said it would take about 10 seconds, yet on average solvers took about 3 minutes (Goranson, 1978). GRABE BARGE

The Scientific Attitude The scientific attitude is composed of curiosity (passion for exploration), skepticism (doubting and questioning) and humility (ability to accept responsibility when wrong). Preview Question 5: What are the three key attitudes of scientific inquiry?

How Do Psychologists Ask and Answer Questions? The Scientific Method Description Correlation Experimentation Preview Question 6: How do psychologists construct theories?

For example, “low self-esteem contributes to depression.” Theory A theory is an explanation using an integrated set of principles that organizes and predicts behavior or events. For example, “low self-esteem contributes to depression.”

Hypothesis A hypothesis is a testable prediction, often prompted by a theory. It enables us to accept, reject or revise the theory. “People with low self-esteem will score higher on a depression test.”

Research and Observations We then test our hypothesis in a controlled setting. Have participants take two tests: one that tests self-esteem (e.g., “agree or disagree: ‘I am fun to be with.’”) and one that test for symptoms of depression. If the hypothesis is correct, people with low scores of self-esteem will have high levels of depression.

Reporting and Replicating Results Psychologists often use an operational definition, a statement of the procedures used to define research variables. E.g., depression may be operationally defined as scoring above a threshold on a depression test. Exact descriptions allow others to replicate the research, repeating the essence of the study to see whether the basic findings extends to other participants and cirumstances.

The Scientific Method

Description As we seek to understand people and refine our theories, we can gather descriptive information in one of three systematic ways: The Case Study Surveys Naturalistic Observation

Case Study Case study: a descriptive technique in which one person is studied in depth in the hope of revealing universal principles. Caveat: Just because something is true of one of us, that does not mean it will be true in all of us. E.g., just because you have an uncle who smokes 3 packs a day and lived to be 100, doesn’t mean smoking doesn’t have adverse health effects. Preview Question 7: What three techniques do psychologists use to observe and describe behavior?

Survey A survey is a descriptive technique for obtaining the self-reported attitudes or behaviors of people, usually by questioning a representative, random sample of them. Important to remember: Wording effects Random Sampling Preview Question 7: What three techniques do psychologists use to observe and describe behavior?

Wording Effects Wording can change the results of a survey. Should cigarette ads and pornography be allowed on television? vs. Should cigarette ads and pornography be forbidden from being on television?

Random Sampling Random sample: a sample that fairly represents a population because each member has an equal chance of inclusion

Surveys Think critically before accepting survey findings Consider the wording and the sample The best basis for generalizing is from a representative sample of cases

Naturalistic Observation A descriptive technique of observing and recording behavior in naturally occuring situations without trying to change or control the situation. Like case studies and surveys, it describes behavior, rather than explaining it. [Insert pic of Frans de Waal from p. 27]

Correlation Correlation: a measure of the extent to which two events vary together, and thus how well either predicts the other. The correlation coefficient expresses the relationship mathematically, ranging from -1 to +1 Positive correlation, noted as a number from zero (no correlation) to 1, means that variables increase and decrease together, like shoe size and height. Negative correlation, a number from 0 to -1, means that one variable going up predicts the other one going down, like self-esteem and depression scores

Correlation and Causation Correlation does not equal causation!

Illusory Correlation The perception of a relationship where no relationship actually exists. For example, we may notice the times that odd behavior happens with a full moon, and develop the illusion that the two events generally tend to go together.

Exploring Cause and Effect Experimentation Exploring Cause and Effect As in other sciences, experimentation is the backbone of psychological research. Experiments isolate causes and their effects. Preview Question 9: How do experiments clarify or reveal cause-effect relationships?

Exploring Cause & Effect Many factors influence behavior. Experiments (1) manipulate factors that interest us, while other factors are kept under (2) control. When we see an effect from manipulating only one variable at a time, we have isolated and discovered a cause-effect relationship.

Experiments Many factors may influence a phenomenon In an experiment, researchers vary one or more factors (independent variables) to observe the effect on some behavior or mental process (dependent variable)

Experiments If possible, participants should be randomly assigned to control and experimental groups Experimental group: exposed to the treatment (one version of the IV) Control group: contrasts the experimental group, serves as comparison to assess the effects of the treatment

Effects of mother’s milk (Lucas et al., 1992) 424 hospital preterm infants randomly assigned to either formula feedings (control) or breast-milk (experimental) Tested at age 8, the breast-milk group scored higher on intelligence tests Random assignment make sure no other difference between the group (mother’s age, intelligence, etc) explains the difference in intelligence scores

Experimentation

Summary: Value of Experiments Correlational studies uncover naturally occurring relationships Unclear about causality Experiments manipulate factors to determine their effects

Tools for Controlling Bias Placebo effect: Expectations about treatment effects can translate to real effects Control groups may be given a placebo – an inactive substance in place of the experimental treatment Many studies are double-blind – neither participants nor research staff knows which participants are in the experimental or control groups.

Comparing Research Methods