Kurt

2007-05-16 16:21:48 UTC

I am trying to assess the level of agreement between two raters who

rated items as either Yes or No. This calls for Kappa. But if one

rater rated all items the same, SPSS sees this as a constant and

doesn't calculate Kappa.

For example, SPSS will not calculate Kappa for the following data,

because Rater 2 rated everything a Yes.

Rater1 Rater2

Item1 Y Y

Item2 N Y

Item3 Y Y

Item4 Y Y

Item5 N Y

SPSS completes the crosstab (which shows that the raters agreed 60% of

the time), but as for Kappa, it returns this note:

"No measures of association are computed for the crosstabulation of

VARIABLE1 and VARIABLE2. At least one variable in each 2-way table

upon which measures of association are computed is a constant."

Is there anywhere to get around this? I can calculate Kappa by hand

with the above data; why doesn't SPSS?

Thanks.

Kurt

rated items as either Yes or No. This calls for Kappa. But if one

rater rated all items the same, SPSS sees this as a constant and

doesn't calculate Kappa.

For example, SPSS will not calculate Kappa for the following data,

because Rater 2 rated everything a Yes.

Rater1 Rater2

Item1 Y Y

Item2 N Y

Item3 Y Y

Item4 Y Y

Item5 N Y

SPSS completes the crosstab (which shows that the raters agreed 60% of

the time), but as for Kappa, it returns this note:

"No measures of association are computed for the crosstabulation of

VARIABLE1 and VARIABLE2. At least one variable in each 2-way table

upon which measures of association are computed is a constant."

Is there anywhere to get around this? I can calculate Kappa by hand

with the above data; why doesn't SPSS?

Thanks.

Kurt