Two Categorical Variables: Fertilizer Treatment and Plant Health

An agricultural researcher is testing whether a new fertilizer treatment reduces plant disease. They randomly assign plants to either fertilizer treatment or control. After growing, they record whether each plant is disease-free or diseased.

Compare the two groups and explore risk, odds, relative risk, and risk difference to understand if the treatment is effective.

To use the interactive with a keyboard, press Tab to move through the controls. When sample size box is selected, use arrow keys to change the value. Then tab to Generate Data or Reset and press Enter.

Setup

Plants per group

Learning mode Real World (unknown population rates) What-if Lab (adjust rates)

What-if: Population healthy rates

Fertilizer: 80%

Control: 40%

Underlying healthy rates used in simulation

Fertilizer: 80%
Control: 40%
Real World mode uses the fixed course settings.

Each click generates a new random experiment.

Click "Generate Data" to start

Results

Healthy

Diseased

Fertilizer Group

Control Group

Group	Healthy	Diseased	Total
Fertilizer	-	-	-
Control	-	-	-
Total	-	-	-

Risk of "Healthy"

Fertilizer group: -
Control group: -

Odds of "Healthy"

Fertilizer group: -
Control group: -

Relative Risk

-

Increased Risk

-

Odds Ratio (Fertilizer odds / Control odds)

-

Risk Difference (Healthy risk with fertilizer - Healthy risk with control)

-

Your results code (paste this into Canvas)