For the models shown below, determine whether it is a linear model, an intrinsically linear model, or a nonlinear model. If the model is intrinsically linear, show how it can be linearized by a suitable transformation.

a. y e x = + + θ ε θ θ 1 2 3

b. y xx = + θθ θ ε + + θ 1 21 2 2 3

c. y = θ1 + θ2 / θ1x + ε

d. θ ε θ θ

11 2 2 3 ( )( ) x x +

e. θ θ ε