Thread: Confidence Intervals for one population mean when stigma is unknown.

1. Confidence Intervals for one population mean when stigma is unknown.

The question is:

Two t-curves have degrees of freedom 12 and 20. Which one more closely resembles the standard normal curve? Explain.

I am thinking that 20 resembles it because of the central limit therom and the fact that t scores spread out much more then z scores. If I am write or wrong, please explain to me in detail what I may be missing.

Thanks =)

2. Originally Posted by l0v3n
The question is:

Two t-curves have degrees of freedom 12 and 20. Which one more closely resembles the standard normal curve? Explain.

I am thinking that 20 resembles it because of the central limit therom and the fact that t scores spread out much more then z scores. If I am write or wrong, please explain to me in detail what I may be missing.

Thanks =)
The answer is df = 20 t-curve. Think about what the pdf of the t-distribution does in the limit df --> oo.