Psychology: A Concise Introduction 5th Edition: Chapter 1

Mode

Number occurring the most

Mean

Numerical average for set of values

2 main aspects of normal distribution

1) Mean, median, and mode all equal because normal distribution is symmetric about its center 2) Percentages of scores falling within certain number of standard deviations of the mean is set

Correlational Study

2 variables being measured to see if they're related (how one predicts the other)

Third Variable Problem

A third variable that could possibly be responsible for observed relationship between 2 variables

Variable

Any factor that can take on more than one value

Standard Deviation

Average extent to which the scores vary from the mean for distribution of scores

External Factors

Behavioral and Sociocultural Perspective

Normal Distribution

Bell shaped frequency distribution

Internal Factors

Biological and Cognitive Perspective

Placebo Group

Control group of participants who believe they're receiving treatment, but are only getting a placebo

Double-Blind Procedure

Control measure in experiment in which neither experimenters nor participants know which participants are in the experimental and control groups

Random Assignment

Control measure in which participants randomly assigned to groups in order to equalize participant characteristics across various gaps in experiment

Spurious Correlation

Correlation in which variables are related through relationship with one or more other variables but not through casual mechanism

Operational Definition

Description of operations or procedures that researcher uses to manipulate or measure a variable

Participant Observation

Descriptive research method in which observer becomes part of group being observed

Positive Correlation

Direct relationship between 2 variables (Ex. Taller you are, more weight you gain)

Population

Entire group of people that researcher is studying

Skewed Distributions

Frequency distributions that are symmetric in shape

Experimental Group

Group exposed to independent variable

Control Group

Group not exposed to independent variable

Range

Highest minus lowest number

Behavioral Perspective

How external environmental events condition our observable behavior

Sociocultural Perspective

How other people and the cultural context impact our behavior and mental processes

Cognitive Perspective

How our mental processes, such as perception, memory, and problem solving, work and how they impact our behavior

Biological Perspective

How our physiology (especially the brain and nervous system) produces our behavior and mental processes and how genetics and evolution have impacted our physiology

Independent Variable

Hypothesized cause and the experimenter manipulates it.

Hindsight Bias

I-knew-it-all-along-phenomenon (Knew what the outcome was going to be, before it happened)

Placebo Effect

Improvement due to expectation of improving because of receiving treatment

Placebo

Inactive pill or sham treatment that has no known effects

Negative Correlation

Inverse relationship between 2 variables (Ex. More you watch TV, lower your scores )

Experiment

Manipulate one or more independent variables in a controlled setting to determine impact on one or more measured dependent variables

Right Skewed Distribution

Mean greater than median

Left Skewed Distribution

Mean less than median

Median

Middle number when re-arranged from lowest to highest

Nocebo Effect

Negative placebo effect due to expectation of adverse consequences from receiving treatment

Frequency Distribution

Organizes data in score distribution so that we know frequency of each score

Percentile Rank

Percentage of scores below specific score in distribution of scores

Case Studies

Study an individual in depth over an extended period of time

Sample

Subset of population that actually participates in research study

Descriptive Methods

Providing objective and detailed descriptions of behavior and mental processes

Survey Research

Representative sample of a group completes questionnaires or interviews to determine behavior, beliefs, and attitudes of the group

Observational Techniques

Researcher observing behavior of interest

Random Sampling

Sampling technique that obtains representative sample of population by ensuring that each individual in population has equal opportunity to be in a sample

Psychology

Science of human behavior and mental processes

Inferential Statistical Analyses

Statistical analyses that allow researchers to draw conclusions about the results of their studies; results are statistically significant if this probability is .05 or less

Meta - Analysis

Statistical technique that combines results of large number of studies on one experiment question into one analysis to arrive at an overall conclusion

Descriptive Statistics

Statistics that describe results of research study in concise fashion

Correlation Coefficient

Strength between 2 variables; Has to be between -1 and 1; closer to 1, the greater the strength

Regression Toward Mean

Tendency for extreme or unusual values on one variable to be matched on average with less extreme values on the other variable when the two variables are not perfectly correlated.

Laboratory Observation

Unobtrusively observe behavior in a laboratory setting

Naturalistic Observation

Unobtrusively observe behavior in its natural setting

Dependent Variable

Variable that's hypothesized to be affected by independent variable; measured by experimenter

Scatter Plot

Visual of correlation data; Each data point represents scores on the 2 variables for each participant