Psychological Statistics Review for Exam 1

This set of flashcards covers key vocabulary terms and concepts relevant to Psychological Statistics that will be tested on Exam 1.

Population

The entire group of individuals or instances about whom we hope to learn.

Sample

A subset of the population used to gather data.

Parameter

A characteristic or measure obtained by using all the data from a population.

Statistic

A characteristic or measure obtained by using data from a sample.

Descriptive statistics

Statistics that summarize or describe the characteristics of a data set.

Inferential statistics

Statistics that allow for making inferences about a population based on a sample.

Nominal scale

A scale that categorizes data without a specific order.

Ordinal scale

A scale that categorizes data with an order but without consistent differences between ranks.

Interval scale

A scale that measures variables with ordered categories and equal intervals, but no true zero.

Ratio scale

A scale that has ordered categories, equal intervals, and a true zero point.

Correlational research

A type of research that measures the relationship between two or more variables without manipulation.

Experimental research

A type of research that manipulates one variable to determine its effect on another variable.

Independent variable

The variable that is manipulated in an experimental study.

Dependent variable

The variable that is measured and is expected to change due to manipulation of the independent variable.

Frequency distribution

A summary of how often each value occurs in a dataset.

Central tendency

A statistic that represents the center or typical value of a dataset.

Mean

The average of a set of values, calculated by summing them and dividing by the number of values.

Median

The middle value in a dataset when the numbers are arranged in order.

Mode

The value that appears most frequently in a dataset.

Standard deviation

A measure of the amount of variation or dispersion in a set of values.

Variance

The average of the squared differences from the mean, representing the spread of a dataset.

Z-score

A measure that describes a value's relation to the mean of a group of values, expressed in terms of standard deviations.