# help understanding t-distribution

#### lilyungn

Hi, I need help understanding how do I use t-distribution to estimate the tα/2 . Also what is meant when it asks "verify your result with empirical rule"

#### mr fantastic

MHF Hall of Fame
Hi, I need help understanding how do I use t-distribution to estimate the tα/2 . Also what is meant when it asks "verify your result with empirical rule"
Values of t for different levels of significance can be read from a table. Most statistics textbooks have such tables (usually in an appendix at the back).

#### lilyungn

Basically i'm working on a problem that asks that part of the question. I have solved for the population mean, and have different samples with 3 data in them. I calculated the x-bar of those samples with the standard dev and have gotten their confidence intervals.

#### CaptainBlack

MHF Hall of Fame
Basically i'm working on a problem that asks that part of the question. I have solved for the population mean, and have different samples with 3 data in them. I calculated the x-bar of those samples with the standard dev and have gotten their confidence intervals.
Could you post the actual question?

CB

#### lilyungn

here is the question: I found the mean, standard dev, samples, their mean and standard dev. I'm stuck at the t-distribution part...I found the confidence interval but someone told me im supposed to use t distribution to do that, so I guess I have to do them over?

Let A, B, C, D, and E are 6 units of a population. The measurements associated with A, B, C. D, E units are 76, 77, 78, 81, and 82, respectively.

- Find the population mean and its standard deviation
- List all possible samples of size 3 from those 5 units
- From each sample, compute the mean, standard deviation, and 95% confidence interval. Use t-distribution to estimate the tα/2 because we have a small size.
- How many intervals contain population mean? Can you verify your result with empirical rule? Do they agree?