hi
I've been using this code to set a reference level for uni and
multivariate analysis
rmix$interviewmethodcode<-relevel(mix$interviewmethodcode,ref="SAQ")
summary(rma.1<-rma(yi,vi,mods=~interviewmethodcode,data=rmix,method="SJ",knha=F,weighted=F,intercept=T))
giving this output:
Model Results:
estimate se zval pval ci.lb ci.ub
intrcpt 0.1437 0.0176 8.1485 <.0001 0.1091
0.1783 ***
interviewmethodcodeACASI 0.0022 0.0412 0.0545 0.9566 -0.0784
0.0829
interviewmethodcodeFTFI -0.0926 0.0656 -1.4112 0.1582 -0.2213
0.0360
However, when i use the same code with a different variable (below) I get the
error message - "Error in qr.solve(wX, diag(k)) : singular matrix 'a' in
solve".
rmix$continent<-relevel(mix$continent,ref="North America")
summary(rma.1<-rma(yi,vi,mods=~continent,data=rmix,method="SJ",knha=F,weighted=F,intercept=T))
Can anyone help to see where the problem is?
thanks
Branwen
hi
I've been using this code to set a reference level for uni and multivariate
analysis
rmix$interviewmethodcode<-relevel(mix$interviewmethodcode,ref="SAQ")
summary(rma.1<-rma(yi,vi,mods=~interviewmethodcode,data=rmix,method="SJ",knha=F,weighted=F,intercept=T))
giving this output:
Model Results:
estimate se zval pval ci.lb ci.ub
intrcpt 0.1437 0.0176 8.1485 <.0001 0.1091
0.1783 ***
interviewmethodcodeACASI 0.0022 0.0412 0.0545 0.9566 -0.0784
0.0829
interviewmethodcodeFTFI -0.0926 0.0656 -1.4112 0.1582 -0.2213
0.0360
However, when i use the same code with a different variable (below) I get the
error message - "Error in qr.solve(wX, diag(k)) : singular matrix 'a' in
solve".
rmix$continent<-relevel(mix$continent,ref="North America")
summary(rma.1<-rma(yi,vi,mods=~continent,data=rmix,method="SJ",knha=F,weighted=F,intercept=T))
Can anyone help to see where the problem is?
thanks
Branwen
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