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VERY Urgent :ct 4 calculation of variance in case of 2 parameters

A

Arpan

Member
a) There are two covariates Z1 = 1 for smoker and 0 for non smoker. Z2 = 1 for male and 0 for female.
b) the parameter estimates are beta1(hat)= .05 and beta2(hat)= 015.
c) the covariance parameter matrix for beta1(hat) and beta2(hat) is

.0002 .0001
.0001 .0003

Determine the upper limit of the 95% confidence interval for the relative risk of a female non-smoker compared to male smoker.

I want to know how variance is to be calculated.


Thanks beforehand.
 
Arpan said:
a) There are two covariates Z1 = 1 for smoker and 0 for non smoker. Z2 = 1 for male and 0 for female.
b) the parameter estimates are beta1(hat)= .05 and beta2(hat)= 015.
c) the covariance parameter matrix for beta1(hat) and beta2(hat) is

.0002 .0001
.0001 .0003

Determine the upper limit of the 95% confidence interval for the relative risk of a female non-smoker compared to male smoker.

I want to know how variance is to be calculated.


Thanks beforehand.
Click to expand...

a11 = Cov(B1,B1) = Var (B1)
a12 = Cov (B1,B2) = a21
a21 = Cov(B2,B1) = a12
a22 = Cov(B2,B2) = Var(B2)
 
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