

Restricting residual variances to be ... 

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I am trying to run a 1factor model with one of the residual variances constrained to remain positive. I've consulted example 5.20 in the new manual, and based on it set up the following: VARIABLE: NAMES ARE y1y5; MODEL: f1 BY y1y5 (V1V5); MODEL CONSTRAINT: V5 > 0; This runs, but the output is the same as if the last two lines were never there. What am I doing wrong? Thanks much! 


v5 refers to a factor loading not a residual variance. To refer to a residual variance, say: y1y5 (v1v5); and remove the labels from the factor loadings. If you continue to have problems, send the input, data, output, and your license number to support@statmodel.com. 


Hi Linda, Thanks for your message. I'm not sure I understand how to modify the syntax. I already say: f1 on y1y5 (v1v5), except I use capital V's. Should I repeat this statement again with lower case v's as you suggest? Also, what does it mean, "remove labels from factor loadings"? 


You refer to residual variances by the name of the variable alone. ON is for regression coefficients. BY is for factor loadings. Try VARIABLE: NAMES ARE y1y5; MODEL: f1 BY y1y5; y1y5 (V1V5); MODEL CONSTRAINT: V5 > 0; 

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