"Christine A. Calmes" <[EMAIL PROTECTED]> wrote: > > [...] Basically, I am trying to test a > psychological model in which a person's level of passive, negative > communication with others in their environment (CORUMTO) on one week > predicts their level of depression on the following week (BDIAFTER) > controlling for their level of depression on the same week that that > they co-ruminate (BDI). The WEEK variable accounts for the fact that > there are 7 weeks worth of data in the model and that scores on adjacent > weeks are more closer related than scores on weeks that are further > apart.
The alternative would be to fit using the sem package, explicitly modelling the time-series and estimating the lagged effects of CORUMTO and BDI -- it may be possible to disentangle the separate effects (a la instrumental variables type analysis). This would be easiest if there are 7 rounds of observations for everyone. The many time series packages may also be usable for this. David Duffy. -- | David Duffy (MBBS PhD) ,-_|\ | email: [EMAIL PROTECTED] ph: INT+61+7+3362-0217 fax: -0101 / * | Epidemiology Unit, Queensland Institute of Medical Research \_,-._/ | 300 Herston Rd, Brisbane, Queensland 4029, Australia GPG 4D0B994A v ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
