# gomez.nonnormal3: RCB experiment of rice, 12 varieties with leafhopper survival In agridat: Agricultural Datasets

## Description

RCB experiment of rice, 12 varieties with leafhopper survival

## Usage

 `1` ```data("gomez.nonnormal3") ```

## Format

A data frame with 36 observations on the following 3 variables.

`gen`

genotype/variety of rice

`rep`

replicate

`hoppers`

percentage of surviving leafhoppers

## Details

For each rice variety, 75 leafhoppers were caged and the percentage of surviving insects was determined.

Gomez suggest replacing 0 values by 1/(4*75) and replacing 100 by 1-1/(4*75) where 75 is the number of insects.

In effect, this means, for example, that (1/4)th of an insect survived.

Because the data are percents, Gomez suggested using the arcsin transformation.

Used with permission of Kwanchai Gomez.

## Source

Gomez, K.A. and Gomez, A.A.. 1984, Statistical Procedures for Agricultural Research. Wiley-Interscience. Page 307.

None.

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29``` ```## Not run: library(agridat) data(gomez.nonnormal3) dat <- gomez.nonnormal3 # First, replace 0, 100 values dat\$thoppers <- dat\$hoppers dat <- transform(dat, thoppers=ifelse(thoppers==0, 1/(4*75), thoppers)) dat <- transform(dat, thoppers=ifelse(thoppers==100, 100-1/(4*75), thoppers)) # Arcsin transformation of percentage p converted to degrees # is arcsin(sqrt(p))/(pi/2)*90 dat <- transform(dat, thoppers=asin(sqrt(thoppers/100))/(pi/2)*90) # QQ plots for raw/transformed data libs(reshape2, lattice) qqmath( ~ value|variable, data=melt(dat), main="gomez.nonnormal3 - raw/transformed QQ plot", scales=list(relation="free")) m1 <- lm(thoppers ~ gen, data=dat) anova(m1) # Match Gomez table 7.25 ## Response: thoppers ## Df Sum Sq Mean Sq F value Pr(>F) ## gen 11 16838.7 1530.79 16.502 1.316e-08 *** ## Residuals 24 2226.4 92.77 ## End(Not run) ```

agridat documentation built on Dec. 20, 2021, 9:07 a.m.