Table 1

Model's description

Model Name

Dependent Variable

Model Specification


Family

Link

v(μ)

Equation


Normal with identity link (OLS)

cost

Normal

Identity

1

E(Y) =

Log Normal*

ln(cost)

Normal

Identity

1

E{ln(Y)} =

Sqrt Normal*

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Normal

Identity

1

E{

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} =

Gamma with log link

cost

Gamma

Log

μ2

ln{E(Y)} =

Gamma with square-root link

cost

Gamma

Square Root

μ2

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=


* Transformation of dependent variable.

Note: μ = E(y) and V(μ) is variance function.

Montez-Rath et al. BMC Medical Research Methodology 2006 6:53   doi:10.1186/1471-2288-6-53

Open Data