Model | Equation | No. of parameters |
---|---|---|
Linear | E[d i |x i ]=θ 1i x i | 1 |
Quadratic | \(\displaystyle \mathrm {E} \left [ \boldsymbol {d}_{i} | \boldsymbol {x}_{i} \right ] = \theta _{1i} \boldsymbol {x}_{i} + \theta _{2i} \boldsymbol {x}_{i}^{2}\) | 2 |
E max | \( \displaystyle \mathrm {E} \left [ \boldsymbol {d}_{i} | \boldsymbol {x}_{i} \right ] = \theta _{1i} \boldsymbol {x}_{i}^{\theta _{3i}}/ \left (\theta _{2i} + \boldsymbol {x}_{i}^{\theta _{3i}} \right)\) | 3 |
Logistic | E[d i |x i ]=θ 1i /{1+exp[(θ 2i −x i )]/θ 3i } | 3 |