what is the constraint in the model what is the relationship between the constraints on the parameters in the model imply that where is the expected value of y_a$ how is the value of alpha used in the model what is the relationship between the constraint on the parameters in the model y_a$ is the mean of the observations that we defined for the special case of the $23$ what is the relationship between the parameters in the model and the original set of parameters? what is the constraint of the model how to write y_a$ on a model what is the constraint on the parameters in the model? why should we write a parameter of the standard model, e which parameters are indexed by the constraint in the model and how to show that the interactions can each be similarly written in terms of a single parameter? how to write the expected value of $e_a$ in a graph what is the relationship between the constraints and the original set of parameters? what is y_a$ and y_a_a$ what is the relationship between the parameter in the model and the original set of parameters how to write the expected value in y_a$ what is the constraint on the parameter in the model how to construct the model x y k what is the relation of y a$ and j a$?