Consider an Experiment Using Birds in Which We Will Use

Multiple Choice

Consider an experiment using birds in which we will use a simple ANCOVA to examine the effects of seed type (low calorie vs. high calorie) and amount of salt eaten (measured by changes in the mass of a salt stick) on feather stiffness. Which of the following is a representation of the model we will use to analyze the data?

A) Feather = constant + seed + salt
B) Feather = constant + seed + salt + seed*salt
C) Salt = constant + seed + feather + seed*feather
D) Seed = constant + salt + feather + salt*feather