Question: In the experiment in Exercise, what does it mean in terms of fish behavior if there is an interaction between presence in sample 1 and presence in sample 2? Between presence in sample 1 and presence in sample 3?

Exercise: Frank (1978) reports on the following experiment to estimate the number of minnows in a tank. The first two samples used a minnow trap to catch fish, while the third used a net to catch the minnows. Minnows trapped in the first sample were marked by clipping their caudal fin, and minnows trapped in the second sample were marked by clipping the left pectoral fin.

Sample 1?         Sample 2?        Sample 3?        Number of Fish

Y                         Y                    Y                      17

Y                         N                    Y                      28     

N                         Y                    Y                      52

N                         N                    Y                      234

Y                         Y                    N                      80

Y                         N                    N                      223

N                         Y                    N                      400

Which loglinear model provides the best fit to these data? Using that model, estimate the total number of fish and provide a 95% CI for your estimate.