Skip to Data Skip to Statistics Skip to Charts

Compare GroupsStatLens

Choose a dataset:

Enter values and group labels (two columns):

#	Value	Group

Open a CSV, TSV, or JSON file:

Quantitative variable: Grouping variable:

Boxplot Dotplot Histogram Density

Summary Statistics

Statistic

Compare Groups

Compare one quantitative variable across the levels of a grouping variable. The chart and the summary-statistics table show every group side by side so you can compare centers, spreads, and shapes.

Quantitative variable — the numeric measurement being compared (for example, height or test score).
Grouping variable — the categorical variable that splits the data into groups (for example, treatment vs control).
Chart type — view the groups as a Boxplot (five-number summary and outliers), a Dotplot (every value as a dot), a Histogram, or a Density curve. Boxplots make centers and spreads easy to line up; dotplots and histograms reveal shape and gaps.

The Summary Statistics table on the right reports n, mean, standard deviation, and the five-number summary for each group. Once data loads, a summary bar appears with buttons to Explore, Preview, or Download the data, and a Change Data button to load something else.

How Q1 and Q3 are computed. Split each group's ordered data at its median and take the median of each half; when n is odd the median itself belongs to neither half. That is the rule in the coursepack and on a TI-84, so quartiles worked out by hand match the box edges drawn here.

?: Show this help
Esc: Close this dialog

New to this tool? Walk through it step by step.

Open guided walkthrough ↗