lettuce: Lettuce data set

In AKitsche/statint: Generating labelled product type interaction contrasts

Description

Simulated data, inspired by the example presented in Bradu and Gabriel.

Usage

lettuce

Format

A data frame with 48 observations on the following 3 variables.

Soil

a factor with levels S1 S2 S3, indicating the soil type

Fertilizer

a factor with levels cal.phos control magn.phos pot.metaphos, indicating the type of phosphate fertilizer

Weight

a numeric vector, indicating dry matter in grams per plot

Details

The experiment was conducted to analyse the effects of soil type and phosphate fertilizers on lettuce crops. The primary response variable was dry matter measured in grams per plot. Three different soil types, namely S1, S2 and S3, and four different levels of phosphate fertilization (including an untreated control) were investigated in a balanced, completely cross-classified treatment structure, laid out as completely randomized design with four replications per treatment combination.

Source

Bradu, D. and Gabriel, K. R. (1974). Simultaneous Statistical Inference on Interactions in Two-Way Analysis of Variance. Journal of the American Statistical Association, 69(346):428-436.

Examples

data(lettuce)
str(lettuce) 

AKitsche/statint documentation built on May 5, 2019, 11:30 a.m.