7.6. Student’s t-Distribution http://www.ck12.org
Points to Consider
- Is there a way to determine where thet-statistic lies on a distribution?
- If a way does exist, what is the meaning of its placement?
Review Questions
- You intend to use simulation to construct an approximatet-distribution with 8 degrees of freedom by taking
random samples from a population with bowling scores that are normally distributed with mean,μ110 and
standard deviation,σ=20.
a. Explain how you will do one run of this simulation.
b. Produce four values oftusing this simulation.
Review Answers
- (a) 8 degrees of freedom mean that the sample size is( 8 + 1 )or 9. The graphing calculator will be used in
order to randomly select scores from a normally distributed population.
This command will select 9 scores from the population and store the values in List One.
These are values selected by the calculator. (b) To calculatet= x ̄−μ
s/
√
n
, enter on the calculator randNorm( 110 , 20 , 9 )L 1 :
(mean(L 1 )− 100 )/(stdDev(L 1 )/
√
9 Press enter 4 times to generate thetvalues.
The mean and stdDev functions are easily found in the catalog of the calculator( 2 nd 0 )