SAS Analysis of Paired Data

2002-04-06


The data are from Statistics 2MA3 Assignment #3 Q4.

period    1    2    3    4    5    6    7    8
pipe   6.64 7.89 1.83 0.42 0.85 0.29 0.57 0.63
brush  9.73 8.21 2.17 0.75 1.61 0.75 0.83 0.56

Enter the data by creating a SAS table in the table editor, or by entering the data in Excel and importing the worksheet into SAS. There should be a column "pipe" and a column "brush" with column names in the first row.

Create a new SAS library called A03, name the table Q4 and save the table in library A03.

This script creates a temporary table TMP1 in library WORK. It contains the variables pipe, brush from A03.Q4, and the new computed variables diff, rat and lograt.

data tmp1;
  set a03.q4;
  diff=brush-pipe;
  rat=brush/pipe;
  lograt=log(rat);
run;
 
proc univariate data=tmp1;
  var diff lograt;
run;

Plot histograms to see which of these variables is the most normal and hence which will give the most valid analysis. To plot the histograms, open WORK.TMP1 in Insight; from the menu, choose Solutions > Interactive Data Analysis.


Statistics 4P03/6P03