Finally we have estimated the relationship between income inequalities and economic development (taking per capita income as an indicator for economic development), and we found that the DSL functional form
is appropriate for Bangladesh, indicating that income inequality will continue to rise with the rise of economic development.
Compared with the more commonly used diagnostic tests for general linear models, such as testing for distribution and homoskedasticity of residuals, formal tests of the assumed functional form
of any independent variables against the dependent variable are scarcely reported in the epidemiologic literature.
Testing the estimated model on this holdout sample indicates that the model with the cubic functional form
is able to predict housing prices more accurately, as indicated by the lower percentage mean absolute error (PMAE).
Rather than stop the analysis at this point, researchers typically use the same data to try out different functional forms
and estimation techniques, and drop weak explanatory variables until plausible or satisfactory results are obtained (or the project is abandoned).
It is therefore tempting to reestimate the aggregator function using a flexible functional form
Using goodness of fit criteria, the linear functional form
provides the best estimate for the market.
Theoretically, the most desirable frontier approaches appear to be those that allow for flexibility with respect to both functional form
and the error term.
The use of a mixture distribution, in contrast to the search for a much more complex functional form
of a single distribution that can handle the observed bimodality, has several advantages.
Given the fitted functional form
for the cost function this is the same for all firms and is significantly greater than one.
An attractive functional form
is the generalized Cross-Carreau description for the shear rate dependency in combination with a pressure-dependent Williams-Landel-Ferry type of equation for the zero shear viscosity, as discussed by Hieber, et al.
In the traditional literature on consumer choice, the indirect utility function is approximated by a specific functional form
in order to obtain expenditure shares and estimates of the important own- and cross-elasticities.
While remaining a functional form
, the blues evolved into a popular form of American entertainment.
Natural frequency feeders, conveyors and shakeouts for foundry applications provided a highly functional form
of movement, improving separation and handling of sand and castings.
Parkin, McGuire, and Yale (1987) argued that estimated income elasticities are sensitive both to the functional form
of the model and to the method by which national currencies have been converted into some standardized unit of account.
However the RESET test for functional form
, which regresses squared residuals on squared fitted values is different in the two cases.