This menu carries out the gamma statistic of agreement for assessing the agreement between two variables measured using
ordinal scales. In GenStat these would each be represented as factors whose levels represent a ranking of the individuals
according to some measurement. For example, suppose we have a factor A with r levels and a factor B with k levels. The data
then consists of an r by k table classified by A and B, whose entries indicate the number of times that the ith
level of variable A occurs with the jth level of variable B. The table must not contain any missing values. The
statistic has the value 1 when there is no disagreement in the ordering of the variables, -1 if the
ordering defined by A has no disagreement with the reverse of the ordering
defined by B, and zero if the variables are independent.
Data
Species a two-way table containing the data.
Create Table
Allows you to create a table either by using existing factors or by using a blank spreadsheet.
Available Data
This lists tables that can be used as data for the test. Double-click on a name to copy it into the Data field, or type the
name in directly.
Method
Controls the type of test that is to be performed. Select Two-sided if you want a two-sided test
(i.e. no prior knowledge is assumed about the type of association). Alternatively, selecting
Positive association will give a one-sided test of the null hypothesis that there is a positive
association and selecting Negative association will produce a one-sided test that there is a negative
association.
See Also