标题: How do we compute DF and T-critical (Exampe #2) [打印本页] 作者: invic 时间: 2013-4-16 15:06 标题: How do we compute DF and T-critical (Exampe #2)
Wanda Brunner, CFA, is trying to calculate a 99% confidence interval for a regression equation based on the following information:
What are the lower and upper bounds for variable CS?
The coefficient for CS is .32
The standard error is .025
My first question is: How do we know it’s a two tailed test?
My second question is: How do we know what the DF are so we can compute T-critical?
This is what they give as the answer:
The critical t-value is 2.42 at the 99% confidence level (two tailed test). The estimated slope coefficient is 0.32 and the standard error is 0.025. The 99% confidence interval is 0.32 作者: Bad5shah 时间: 2013-4-16 15:11
CPK
Can you please compute DF from the data given above?
thanks作者: cfalevel2011 时间: 2013-4-16 15:17
they should’ve given you the number of sample points… haven’t they?
in the absence of that - you cannot do this ….作者: genuinecfa 时间: 2013-4-16 15:21
man - it gives you df=40 on the question… at least when I look at the question online作者: Kapie 时间: 2013-4-16 15:24
also the online version says 98% confidence interval (df=40).
possibly an update of QBank is called for.作者: ayodayo 时间: 2013-4-16 15:26
I use the qbank, but not the online qbank. I use the qbank that is downloaded to the hard-drive.
On my question, the df is not given :-(