st: estimating related models

[Richard Goldstein <richgold@ix.netcom.com>]

I will soon be estimating two regression models that look, in simplified form, 
as follows:

heart rate = f(systolic blood pressure, systolic diameter)

sympathetic nerve activity = f(diastolic blood pressure, diastolic diameter)

Since the two types of blood pressure are clearly related to each other, these 
appear to be related models.

I have done a little reading about sureg and that might fit (the relationship 
through the predictors might result in a relationship of the residuals), but 
I'm not familiar with this type of estimation so I'm not sure and am 
requesting advice from others on the list.

Also, any other advice about estimating these models to account for the 
relationship across the predictors would be welcome.

Thanks,

Rich Goldstein

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