AP Psychology- Unit 0

Experiment

Experiment

A way of confirming the validity of psychological findings with consistent and repeatable results

Hypothesis

testable prediction, not yet confirmed or unconfirmed

Operational Definitions

a carefully worded statement of the exact procedures, helps with future replication

Theories

explanations that organize and predict

Intuition

an effortless feeling/thought, often incorrect

Bias

prejudice in favor of or against a thing

Experimental Group

the group being tested/exposed

Control Group

the group NOT being tested/exposed

Independent Variable (IV)

manipulated factor

Dependent Variable (DV)

consistent factor

Random Selection

a random selection of a diverse population used to eliminate bias

Random Assignment

subjects placed in experimental/control groups at random to eliminate bias

Large Sample Size

helps increase accuracy and validity of data by limiting confounding variables

Convience Sampling

technique where subjects are chosen based on proximity/accessibility (diminishes integrity)

Confounding Variables

factors that cause differences between the experimental group and the control group other than the IV (age, gender, home life, etc.)

Control Variables

anything held constant to reduce confounding variables

Sampling Bias

when a sample is not representative of the population from which it is drawn

Experimenter Bias

when the experimenter (intentionally or unintentionally) influences the results to portray a certain outcome

Social Desirability Bias

the tendency of survey respondents to give socially approved answers to questions about oneself

Correlation Study

study that determines the relationship between 2 variables

Naturalistic Observations

unhindered observations in a natural environment

Case Study

study of one individual in great detail

Meta-Analysis

a procedure for statistically combining the results of many different research studies

Bar Graphs

a graph with bars and gaps representing categories and numerical values

Histogram

a bar graph depicting a frequency distribution

Scatterplots

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 between the two variables, the amount of scatter suggests the strength of the correlation

Quantitative

Data that is in numbers

Qualitative

Data in the form of words

Correlation Coefficient

measures the relationship strength between 2 variables ranging from -1 to 1

Positive Correlation

above 0

Negative Correlation

below 0

Positive Skew

Right

Negative Skew

Left

Bimodal

data set with two peaks

Bell Curve

data set with one peak

Central Tendencies

typical value for a probability distribution

Mode

most frequently occurring score

Mean

average

Median

the middle score in a distribution

Range

the difference between the highest and lowest scores

Percentile

A point on a ranking scale of 0 to 100

Standard Deviation (SD)

measures the average difference between each score and the mean of the data set

Statistical Significance

how likely it is that an obtained result occurred by chance

Psychological Institutions

The American Psychological Association (APA) and British Psychological Society (BPS) determine the ethics and
procedures, and requires compliance from any prospective experimenters

HIPAA Privacy Rule

Law that regulates the use and disclosure of patients' protected health information (PHI).

IACUC (Institutional Animal Care and Use Committee)

committee that approves or denies permission for studies involving animals

Experimental Prerequisites

1) Obtain informed consent of the subjects
2) Protection from physical harm or discomfort
3) Confidentiality regarding subject information
4) A full debrief of the results for subjects afterwards

Informed Assent

-case in which child is informed about what is going to be required and they have the opportunity to agree to or disagree to treatment
-children of different ages require different levels of confidentiality

Critical Thinking

thinking that does not blindly accept arguments and conclusions. Rather, it examines assumptions, discerns hidden values, evaluates evidence, and assesses conclusions.

Hindsight Bias

the tendency to believe, after learning an outcome, that one would have foreseen it

Falsifiable

the possibility that a hypothesized relationship can be shown to be incorrect

Survey

non-experimental method for obtaining the self-reported attitudes or behaviors of a particular group

Self-Report Bias

bias when people report their behavior inaccurately

Random Sampling

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

Population

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

Variable

anything that can vary and is feasible and ethical to measure

Illusory Correlation

perceiving a relationship where none exists, or perceiving a stronger-than-actual relationship

Regresson Toward the Mean

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

Placebo Effect

the phenomenon in which the expectations of the participants in a study can influence their behavior

Validity

the extent to which a test measures or predicts what it is supposed to

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

numerical data used to measure and describe characteristics of groups. Includes measures of central tendency and measures of variation.

Inferential Statistics

numerical data that allow one to generalize- to infer from sample data the probability of something being true of a population

Effect Size

the strength of a relationship between two or more variables