STAT 101- Exam 4 (Ch. 15 II 18-21) Iowa State University questions and answers passed

STAT 101- Exam 4 (Ch. 15 II 18-21) Iowa State
University questions and answers passed
1. Population mean Unknown mean value of the quantitative
variable from the population




2. Population standard deviation Unknown standard deviation of the
quantitative
variable from the population




3. Sample mean Mean value of the quantitative variable from
the sample; x is y in our terms




4. Sampling distribution of sample mean N (u, o/square root of n)




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,STAT 101- Exam 4 (Ch. 15 II 18-21) Iowa State
University questions and answers passed
5. Standard error of the sample mean




6. The t distribution Has a parameter to keep track of the
"degrees of freedom"




7. Degrees of freedom n-1 where n is the sample size

8. Assumptions needed for the t- Randomization condition, 10% condition,
distrib- ution Nearly Normal Population Distribution
Condition

9. Properties of t-distribution Symmetric around 0, bell-shaped, more
probability
in tails of the distribution compared to the
normal distribution, becomes closer to normal
model as sample size gets larger

10. Inference for the population mean mu Find a confidence interval for unknown
population
mean, Confidence interval gives interval of
values that are plausible for parameter of
interest-un- known parameter could be A C
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, STAT 101- Exam 4 (Ch. 15 II 18-21) Iowa State
University questions and answers passed
% confidence inter- val for mu; y line +- t*
s/ square root of n

11. t distribution table




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