Sabre

MASS

Sabre manual

Syntax: MASS number
or
MASS keyword=number [ keyword=number [ keyword=number]] where number is 1,2,4,6,8,10,12,14,16,20,24,28,32,36,40,44,48,56,64,72, 80,88,96,104,112,128,144,160,176,192,208,224,240 or 256 and keyword is FIRST, SECOND or THIRD.

Purpose:
MASS number sets the number of quadrature points used in the numerical integration as part of the model fitting process in univariate models instigated by the FIT command.

MASS FIRST=number specifies the number of quadrature points for the first response in bivariate or trivariate models.

MASS SECOND=number specifies the number of quadrature points for the second response in bivariate or trivariate models.

MASS THIRD=number specifies the number of quadrature points for the third response in trivariate models.

The default number of quadrature points used is 12.

A large number of mass points will produce more accurate integration, but will increase the time taken for each iteration.

For binary data, using a mass point of 1 with end-points free is equivalent to ignoring the case-structure of the data, and fits the famous mover-stayer model of Blumen et al (1957).

Using a mass point of 1 with end-points fixed at zero is equivalent to a standard logistic/log-linear model (and thus to using the LFIT command).

The MASS setting has no effect on the LFIT command.

The current setting of the MASS parameter may be obtained by issuing the DISPLAY SETTINGS command.