Chapter 1 Psych

Theory

explains behaviors or events by offering ideas that organize what we have observed. An explanation using an integrated set of principles that organizes observations & predicts behaviors or events; can be proven or disproven

Hypothesis

testable predictions; often implied by the theory

Operational Definition

a 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 findings extends to other participants & circumstances

Descriptive Methods

describes behaviors; often through case studies, surveys, or naturalistic observations

Correlational Methods

associates different factors

Experimental Methods

manipulates factors to discover their effects

Case Study

descriptive technique in which one individual or group is studied in depth in hope of revealing universal principles

Naturalistic Observation

watching & recording the natural behavior of many individuals

Survey

descriptive technique for obtaining the self-reported attitude or behaviors of a particular groups , usually by questioning a representative, random sample of the group

Population

all those in a group being studied from which sample may be drawn

Random Sample

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

Correlation

a measure of the extent to which two factors vary together, & thus how well either factor predicts the other

Correlation Coefficient

a statistical index of the relationship between two things

Scatterplot

graphed cluster of dots which represent values of two variables slope suggests direction of relationship. Amount of scatters suggest strength of correlation. + slope = positive direct proportion, 0.0 = no correlation, - negative direct proportion

Illusionary Correlation

remembering more confirming things than disconfirming things

Regression Towards the Mean

tendency for extreme or unusual scores or events to fall back (regress) towards the average

Experiment

research method where one manipulates 1+ factors to observe effect a behavior or mental process

Experimental Group

groups in an experiment exposed to treatment, one version of the independent variable

Control Group

group in an experiment not exposed to treatment/independent variable serves as comparison between groups

Random Assignment

assigning people to control or experimental group by chance to minimize preexisting differences

Double Blind Procedure

experiment procedure where neither the participant nor the researcher knows who is in control or experimental group

Placebo Effect

experimental results caused by expectation alone; when someone improves because they think they are getting the experimental thing

Independent Variable

factor that can be/is manipulated; variable whose affect is being studied

Confounding Variable

factor other than the independent variable that might produce affect

Dependent Variable

outcome that is measured; variable may change when independent variable changes

Theoretical Principles

principles/ideas - not the actual findings to help explain everyday behaviors

Informed Consent

giving potential participants enough information about a study to enable them to choose whether they wish to participate

Debriefing

the post-experimental explanation of a study, including its purpose and any deceptions to its participants

Descriptive Statistics

summary statistics that quantitatively describe or summarize feature from a data set

Mode

most frequent value in a data set

Mean

the arithmetic average of a distribution obtained by adding the scores & dividing them by the \# of scores

Median

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

Measures of Central Tendency

single score that represents a whole set of scores; neatly summarize data

Range

the difference between the highest & lowest scores in a distribution

Standard Deviation

a computed measure of how much scores vary around the mean score

Normal Curve

a symmetrical, bell-shaped curve that describe the distribution of many types of data; most scores land near the mean

Inferential Statistics

use of measurements from the sample of subjects in the experiment to compare the treatment groups & make generalizations about the large population of subjects

Statistical Significance

a statistical statement of how likely it is that a obtained result occurred by chance