" Exercise 2.1

 Statistical Methods in Biology: Design and Analysis of Experiments and Regression
 by S.J. Welham, S.A. Gezan, S.J. Clark & A. Mead (2014)
 Chapman & Hall/CRC Press, Boca Raton, Florida. ISBN: 978-1-4398-0878-8
 Version 1, 16/09/2014 "

" Set working directory - change to location of your data file "
\SET [WORKINGDIRECTORY='d:/stats4biol/data/']

" Read data from working directory "
FILEREAD [NAME='GRASS.DAT'; IMETHOD=read] FGROUPS=no

" Bar chart "
" Set up factor with all possible numbers of plants per quadrat 
  & assign counts as factor values "
FACTOR [LEVELS=!(0,1,2...15); VALUES=#Count] IDENTIFIER=fCount
" Get frequency table of counts "
TABULATE [CLASSIFICATION=fCount; COUNTS=Freq]
PRINT Freq
" Set up axis labels "
YAXIS WINDOW=1; TITLE='Number of quadrats'
XAXIS WINDOW=1; TITLE='Number of plants'
" Plot bar chart"
BARCHART [KEY=0] DATA=Freq; PEN=1

" Sample statistics "
DESCRIBE [SELECTION=mean,median,q1,q3] DATA=Count

" Box plot with mean added as reference level "
CALCULATE Mean=MEAN(Count)
BOXPLOT [AXISTITLE='Number of plants'; REFERENCELINE=Mean] DATA=Count 

" End of File "