Psychology Key Terms: Bias, Variables, Research Methods, and Data Analysis

Confirmation Bias

the tendency to look for or notice info that supports what you already believe while ignoring info that disagrees

Hindsight bias-The tendency to believe, after something happens, that you knew it would happen all along

Overconfidence

The tendency to be more confident in your knowledge or abilities than is justified by the evidence

Independent vs. Dependent Variable

IV; The variable that is changed or controlled in an experiment. DV; The variable that is measured to see whether it was affected by the independent variable

Random Assignment

Placing participants into different experimental groups by chance, helping make the groups similar

Case Study

An in-depth investigation of one person, group, or situation

Correlation

A relationship between two variables in which changes in one variable are associated with changes in another; doesn't = causation

Meta

- A study that combines the results of many previous studies to find an overall pattern or conclusion

Naturalistic Observation

Observing and recording behavior in a person's or animal's normal environment without interfering

Hypothesis

A testable prediction about the relationship between variables

Falsifiable Hypothesis

A hypothesis that can be tested and possibly proven false

Operational Definitions

Specific, measurable descriptions of how a researcher will define and measure a variable

Confounding Variables / Third Variable Problem

An outside variable that affects the results and can make it difficult to determine whether one variable actually caused a change in another

Histogram

A graph that shows how numerical data was distributed across intervals or ranges

Scatterplot (Correlational Coefficient)

A graph that uses dots to show the relationship between two numerical variables

Central Tendency

A way of describing the typical or center value of a set of data, usually using the mean, median, or mode

Variation

The amount by which data values differ from one another

Percentile Rank

The percentage of scores that fall at or below a particular score

Range

The difference between the highest and lowest values in data

Population

The entire group of people or subjects that a researcher wants to study

Representative Sample

A smaller group that closely reflects the important characteristics of the population being studied

Random Sample

A sample chosen so that every member of the population has an equal or known chance of being selected

Convenience Sampling

Choosing participants because they are easy for the researcher to reach

Sampling Bias

A problem that occurs when the sample does not accurately represent the population

Generalization

Applying the results of a study to a larger population beyond the participants who were studied

Experimental Group

The group in an experiment that receives the treatment or independent variable being tested

Control Group

The group that does not receive the experimental treatment and is used for comparison

Placebo

An inactive treatment that looks like real treatment and is used as a comparison

Single Blind

A study in which the participants do not know which group they are in, but researchers do

Double Blind

A study in which neither the participants nor the researchers directly interacting with them know who is receiving the treatment

Experimenter Bias

When a researcher's expectation unintentionally influence how a study is conducted or interpreted

Social Desirability Bias

When people give answers they think will make them look better or more socially acceptable

Qualitative (Structured Interviews)

Research that collects non-numerical info, such as people's experiences, opinions, or descriptions

Quantitative Measures (Likert Scales)

Measures that collect numerical data that can be counted or statistically analyzed

Peer Review

When other experts evaluate a research study before it's published

Replication

Repeating a study to see whether similar results can be obtained again

Statistical Significance

A statistical indication that a result is unlikely to have occurred simply because of random chance, based on a chosen significance level

Size of Sample and Statistical Significance

Larger samples generally provide more precise estimates and can make it easier to detect statistically significant effects, although a large sample doesn't automatically make an effect meaningful

Self Report Bias

Errors that occur when people report info about themselves inaccurately, intentionally or unintentionally

Social Desirability Bias

When someone gives an answer they think will make them look better or more socially acceptable