Workspace Node: GLZ Custom Design - Specifications - Quick Tab

The GLZ Custom Design workspace node can be accessed from the Feature Finder, ribbon bar, or Node Browser. The Quick tab of the specifications dialog box is displayed by default when you double-click the node.

Generalized linear model. This list contains the most typical models for a design.

Element Name Description
Logit model Select Logit model to set the Distribution to Binomial and the Link function to Logit.
Probit model Select Probit model to set the Distribution to Binomial and the Link function to Probit.
Multinomial logit model Select Multinomial logit model to set the Distribution to Multinomial and the Link function to Logit.
Ordinal logit model Select Ordinal logit model to set the Distribution to Ordinal multinomial and the Link function to Logit.
Ordinal probit model Select Ordinal probit model to set the Distribution to Ordinal multinomial and the Link function to Probit.
Poisson log model Select Poisson log model to set the Distribution to Poisson and the Link function to Log.
Normal log model Select Normal log model to set the Distribution to Normal and the Link function to Log.
Tweedie log model Select Tweedie model to set the Distribution to Tweedie and the Link function to Log.
Negative binomial log model Select Negative binomial log model to set the Distribution to negative binomial and the Link function to Log.
Distribution, Link functions Select the Distribution and Link functions for the dependent (response) variable in the respective lists. The link function in the generalized linear model specifies a nonlinear transformation of the predicted values so that the distribution of predicted values is one of several special members of the exponential family of distributions (e.g., normal, Gamma, Poisson, Binomial, Tweedie, etc.). The link function is therefore used to model responses when a dependent variable is assumed to be nonlinearly related to the predictors. Various link functions (see McCullagh and Nelder, 1989) are commonly used, depending on the assumed distribution of the dependent variable (y) values. When you select a distribution in the Distribution list, the available choices in the Link functions list will change accordingly.
Normal, Poisson, Gamma, Inverse normal, Tweedie, and Negative Binomial distributions When any of these Distributions are selected, the following choices are in the Link functions list:

Log link: f(z) = log(z)

Power link: f(z) = za, for a given a

Identity link: f(z) = z

Binomial, and Ordinal multinomial distributions When the Binomial or Ordinal multinomial Distribution is selected, the following choices are in the Link functions list:

Logit link: f(z) = log(z/(1-z))

Probit link: f(z) = invnorm(z) where invnorm is the inverse of the standard normal cumulative distribution function (see Distributions and their functions).

Log-Log link: f(z) = -log(-log(z))

C(omplementary)-Log-Log link: f(z) = log(-log(1-z))

Multinomial distribution When Multinomial Distribution is selected, the following choice is in the Link functions list:

Generalized Logit link: f(z1|z2, ..., zc) = log(z1/(1-z1-...-zc)) where the model has c+1 categories.

Weighted moments Select the Weighted moments check box to specify that each observation contributes the weighting variable's value for that observation. The weight values need not be integers. This module can use fractional case weights in most computations. This option will only be available after you have defined a weight variable via the W option.
DF = W-1 / N-1 When the Weighted moments check box is selected, moment statistics (e.g., mean, variance) can be based on the sum of the weight values for the weighting variable (W-1), or on the number of (unweighted) observations (N-1). The sums of squares and cross products will always be based on the weighted values of the respective observations. However, in computations requiring the degrees of freedom (e.g., standard deviation, ANOVA tables), the value for the degrees of freedom can either be computed based on the sum of the weight values, or based on the number of observations. Moment statistics are based on the sum of the weight values for the weighting variable if the W-1 option button is selected, and are based on the number of (unweighted) observations if the N-1 options button is selected. For more information on options for using integer case weights, see also Define weight.
Power parameter Type in the power parameter, or use the microscrolls to adjust the number. This option is available only when Power is selected as the Link function. The power link function is defined as f(z) = za, for a given a.
Index parameter Type in the index parameter, or use the microscrolls to adjust the number. This option is available only when Tweedie is selected as the distribution. It defines the variance function as V(µ) = µIndex Param.  This parameter is restricted such that 1 < Index Param. < 2. This defines a mixed distribution or a Poisson-Gamma distribution with support greater than 0 and a mass at 0.
Dispersion Param Type in the dispersion parameter, or use the microscrolls to adjust the number. This option is available only when Negative binomial log model is selected as the distribution. The value of the dispersion parameter is restricted to be equal to or greater than zero. An entered value of zero means the dispersion parameter is estimated via maximum likelihood. Otherwise, the entered constant value is used for the dispersion parameter. This enables you to model the data according to a Poisson-Gamma mixture distribution.

Options / C / W. See Common Options.

OK Click the OK button to accept all the specifications made in the dialog box and to close it. The analysis results will be placed in the Reporting Documents node after running (updating) the project.

See also, Specifications - Model Specification tab, Specifications - Advanced tab, Results - Summary tab, Results - Residuals 1 tab, Results - Residuals 2 tab, Results - Means tab, Results - Code Generator tab, Downstream tab, and Home tab.