Chapter 1- Thinking Critically With Psychological Science

Sources of Intuition Overestimation

Hindsight bias, Overconfidence, Tendency to perceive patterns in random events 

Hindsight bias

I knew it all along phenomenon; the tendency to believe, after learning an outcome, that one would have foreseen it

Overconfidence

We think we know more than we do

Tendency to perceive patterns in random events

Post truth

Describing a modern culture where peoples emotions and personal beliefs often override their acceptance of objective facts

False news

Misinformation fed to us intentionally

Repetition

Statements become more believable when they are repeated

Availability of powerful examples

Vivid images of death

Group identity & Echo chamber of the like minded

Social identities matter in groups, read news sources that affirm our views and demonize news sources that do not

Scientific Method

The process of testing ideas about the world

Theory

Explanation using an integrated set of principles that organized observations and predicts behaviors or events 

Hypothesis

Testable prediction, often implied by a theory

Operational definition

Carefully worded statement of the exact procedures (operations) used in a research study

Replication

Repeating the essence of a research study, usually with different participants in different situations, to see whether the basic finding extends to other participants and circumstances 

A good theory 

• Effectively organizes a range of self reports and observations

• Leads to clear predictions that anyone can use to check the theory 

• Often stimulates research

• May be replicated

Descriptive research

a systematic, objective observation of people

Descriptive research goal

Its goal is to provide a clear, accurate picture of people's behaviors, thoughts, and attributes

Case study

Examines one individual in depth, Provides fruitful ideas, Cannot be used to generalize conclusions

Naturalistic observation

Records behavior in natural environment, Describes but does not explain behavior, Can be revealing

Survey

A descriptive technique for obtaining the self reported attitudes or behaviors of a group, usually by questioning a representative, random sample of that group

Wording effect 

Random sampling

Uses random sampling of the population for the best results

Correlation Research Strategy

An observation that two traits or attributes are related to each other (that is, they are “co”-related

Positive correlation (between 0 and +1.00)

Indicates a direct relationship: two things increase together or decrease together 

Negative correlation (between 0 and -1.00)

Indicates an inverse relationship: as one thing increases, the other decreases

Correlation coefficient 

Provides a statistical measure of how closely two things vary together and how well one predicts the other

Scatter plots show patterns of correlation

Correlations can range from +1.00 (scores on one measure increase in direct proportion to scores on another measure) to 0.00 (no relationship) to -1.00 (scores on one measure decrease precisely as scores rise on the other)

What is the relationship between correlation and causation?

Correlation does not prove causation

Experimentation Research Strategy

Researchers can focus on the possible effects of one or more factors in several ways 

What are the two groups in an experiment?

Experimental and control

Double blind procedure

Neither those in the study nor those collecting the data know which group is receiving the treatment

What does a double blind procedure allow for?

Treatments actual effects can be separated from potential placebo effect

Placebo effect

Effect involves results caused by expectations alone 

What are the three variables in an experiment?

Independent, Dependent, Confounding

Independent variable

Factor that is manipulated; the variable whose effect is being studied 

Dependent variable

Factor that is measured; the variable that may change when the independent variable is manipulated 

Confounding variable

Factor other than the independent variable that might produce an effect 

Experiment purpose

Test theoretical principles; do not re-create exact everyday life behaviors 

Resulting principles 

Help can explain everyday behavior, not specific findings

Psychological science 

Focuses primarily on seeking general principles that help explain many behaviors and less on particular behaviors 

Mode

most frequently occurring scores in a distribution

Mean

average; can be distorted by atypical scores

Median

middle score in a distribution; half the scores are above it, and half are below it

When is an observed difference significant?

When sample averages are reliable and the difference between them is relatively large the difference has statistical significance, meaning that it is probably not due to chance variation between the samples

The normal curve

Bell Curve