Datasets for Statistical Analysis

Barley yield and manure

Keywords:

manure, barley, fertilizer, split plot

Categories:

biology;
designed experiments

Description:

The data come from an a classic experiment to measure the effect of manure on the yield of barley. Six blocks of three whole plots were used, together with three varieties of barley. Each whole plot was divided into four subplots to cater for the four levels of manure: 0, 0.01, 0.02 and 0.04 tons per acre. The block and variety types are both qualitative variables and so some coding is necessary to include them into a regression model. The data form a completely randomized design.

There are 72 observations on four variables.

Variables:

Block	The block used (coded 1, 2, 3, 4, 5, 6)
Variety	The variety of barley (coded 1, 2 or 3)
Manure	The amount of manure used, either 0, 0.01, 0.02 or 0.04 tons per acre. These have been coded as 0, 1, 2 and 4 respectively, and so can be treated as an ordered factor.
Yield	The barley yield (units unknown)

Data Quality:

There are no missing values.

Source:

Hand et al. dataset 320.

Notes:

References: