Psychological Statistics || Module 2

Descriptive Statistics

Summarize and understand features of a data set.

Measures of Central Tendency

Find the middle or average of a dataset.

Measures of Spread

Describe variability in observed values for a variable.

Mode

Most frequently occurring value in a dataset.

Median

Middle value in a dataset when arranged in order.

Mean

Sum of all values divided by the total number of values.

Range

Difference between the highest and lowest values.

Quartiles

Values that divide a dataset into four equal parts.

Interquartile Range

Range of the middle 50% of values in a dataset.

Variance

Measure of how spread out the values in a dataset are.

Standard Deviation

Square root of the variance, indicating dispersion.

Weighted Mean

Mean that considers weights assigned to values based on importance.

Midpoint

Middle value of a class interval in grouped data.

Frequency Distribution

Arrangement of data into classes showing the frequency of each.

Cumulative Frequency

Running total of frequencies in a frequency distribution.

Unimodal

Distribution with one mode.

Multimodal

Distribution with two or more modes.

Bimodal

Distribution with two modes.

Trimodal

Distribution with three modes.

Interquartile Range (IQR)

Difference between the upper and lower quartiles.