Back to the previous page

 

Trap types

You are a pest control professional who wishes to test the effectiveness of three different traps for catching rats. A trap of each design is set out and their positions interchanged periodically to eliminate the effects if other variables. The numbers of rats caught in each type of trap over the study period are recorded here. Is there a significant difference in the effectiveness of the three types of trap?

Note: These data are in their “tallied” up form (see starting point).

 

Capture data for three types of trap

Trap type	Observed frequency
Trap A	10
Trap B	27
Trap C	15

Expected frequencies are equal (17)