which of the following is not needed to compute t statistic?

1. a hypothesized value for the population mean
2. The value of the population variance or standard deviation
3. The value of the sample mean
4. The value of the sample variance or standard deviation

Question

which of the following is not needed to compute t statistic?

1. a hypothesized value for the population mean
2. The value of the population variance or standard deviation
3. The value of the sample mean
4. The value of the sample variance or standard deviation

jim_thompson5910 · Answer

any ideas?

anonymous · Answer

I was thinking number 1 but not really sure

jim_thompson5910 · Answer

you do need the hypothesized value for the population mean

it's used in computing xbar - mu

mu = population mean

jim_thompson5910 · Answer

check out this page http://stattrek.com/probability-distributions/t-distribution.aspx

anonymous · Answer

Thank you

jim_thompson5910 · Answer

so which one is it?

anonymous · Answer

Is it number 3?

jim_thompson5910 · Answer

xbar is the sample mean

jim_thompson5910 · Answer

you need that to compute xbar - mu

anonymous · Answer

oh okay and would it be number 4 because we are using the population mean and not the sample?

jim_thompson5910 · Answer

actually it's the other way around

jim_thompson5910 · Answer

we use the sample std dev

jim_thompson5910 · Answer

we often don't know the population std dev

jim_thompson5910 · Answer

but we can calculate the sample std dev

anonymous · Answer

oh okay I understand it thank you very much

jim_thompson5910 · Answer

np