Statistics in Psychology

These flashcards cover key terms and concepts related to statistics in psychology, focusing on descriptive statistics, inferential statistics, and hypothesis testing.

Central tendency

The point around which scores are clustered in the distribution of a quantitative variable.

Mean

The average score in a data set.

Median

The middle score when all scores are arranged in order.

Mode

The score that appears most frequently in a data set.

Range

The value of the largest measurement minus the smallest measurement in a data set.

Variance

A statistic that represents the sum of squares divided by the sample size.

Standard deviation

A statistic that describes the average difference between the measurements in a frequency distribution and the mean of that distribution.

Descriptive statistics

Numbers like the mean, median, mode, and standard deviation that summarize important elements of the distribution of a measured variable.

Frequency distribution

A table that indicates how many participants fall into each of the categories.

Histogram

A visual depiction of the frequency distribution using bars to illustrate the frequencies.

Outliers

Scores that are extremely high or extremely low compared to the rest of the data.

Inferential statistics

Use results from a sample to generalize conclusions about a population.

Statistical significance

Indicates that a result is not likely to have occurred by chance, typically defined as p < .05.

T-test

A statistical test that determines whether there is a significant difference between the means of two groups.

Null Hypothesis (H0)

A statement that there is no effect or no difference, and it is what is tested in a t-test.

Alternative Hypothesis (HA)

The hypothesis that there is a significant difference or effect.

Pearson product-moment correlation coefficient

A statistic used to represent the direction and strength of the relationship between two variables.