Overview

The Data tab is where you tell Prism which variables from your Multiple Variables table to include in the analysis. You'll specify:

•Which variable is your response (Y) variable - the outcome you want to analyze

•Which variables are your grouping variables (factors) - the categorical predictors that define your experimental groups

This is the first tab you'll see when you select Multifactor ANOVA from the Analyze menu.

The Variable Assignment Interface

The Data tab for Multifactor ANOVA is divided into three main sections:

Available variables (left panel):

•Shows all variables (columns) from your Multiple Variables table

•Variables are indicated by icons:

oLine icon (): Continuous numeric variable (potential response variable)

oBar icon (): Categorical variable (potential grouping variable)

•Use the search box to filter variables by name

Response (Y) variable (top right panel):

•This is where you specify the outcome variable you want to analyze

•For Multifactor ANOVA, you may only specify a single response variable

Grouping variable(s) (bottom right panel):

•This is where you specify your factors (categorical predictors)

•Select two or more grouping variables to include in your model

•These define the groups you're comparing

Assigning and Removing Variables

To assign a response variable:

1.In the Available variables panel, find your response variable (the outcome you measured)

2.Click and drag it to the Response (Y) variable or grouping variable(s) panel, OR

3.Click on the Add button (plus icon) in the response variable or grouping variable(s) panels, then search or select the desired variable from the list that appears

a.You may only add a single response variable for multifactor ANOVA

b.You may add as many grouping variables (factors) as needed

Example: In a plant growth experiment, you would drag "Height" to the Response panel. You might also drag "Fertilizer", "Watering", and "Light" to the Grouping variables panel to conduct a "three-way ANOVA" on this data

 

To remove a variable:

1.In the Response or Grouping panel, find the variable you want to remove

2.Click and drag it back to the Available variables panel, OR

3.Hover your mouse over the variable and click the Remove button (x icon)

Example: Setting Up a 3-Factor Analysis

Scenario: You're analyzing plant height as affected by Fertilizer type, Watering frequency, and Light exposure.

Your Multiple Variables table has these columns:

•PlantID (identification)

•Height (continuous)

•Fertilizer (3 levels: None, Organic, Synthetic)

•Watering (3 levels: Daily, Weekly, Biweekly)

•Light (3 levels: Shade, Partial, Full)

Step 1: Identify variables to use

•Response: Height

•Grouping variables: Fertilizer, Watering, Light

•Don't use: PlantID (identification), Notes (not a grouping variable)

Step 2: Assign response variable

•Find "Height" in Available variables (should have line icon )

•Drag to Response (Y) variable(s) panel

•Verify it appears in the Response panel

Step 3: Assign grouping variables

•Find "Fertilizer" in Available variables (should have bar icon )

•Drag to Grouping variable(s) panel

•Repeat for "Watering"

•Repeat for "Light"

•Verify all three appear in the Grouping variables panel

Step 4: Verify setup

•Response panel contains: Height

•Grouping panel contains: Fertilizer, Watering, Light

•Available variables panel contains: PlantID, Notes (unused)

Step 5: Click OK or proceed to the Model tab