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# Confidence Intervals, Differences Between T And Z Distribution

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1. What do confidence intervals represent? What is the most controllable method of increasing the precision (narrowing) of the confidence interval? What percentage of times will the mean (population proportion) not be found within the confidence interval?

2. As a sample size approaches infinity, how does the t distribution compare to the normal z distribution? When you draw a sample from a normal distribution, what can you conclude about the sample distribution? Explain.

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1. What do confidence intervals represent?
Confidence intervals represent ESTIMATION, about "the true mean of a population based on a random sample."
See: http://www.cvgs.k12.va.us/DIGSTATS/main/descriptv/d_confidence.htm

* What is the most controllable method of increasing the precision (narrowing) of the confidence interval?
The most controllable method of increasing precision or narrowing the confidence interval is to adjust the ...

#### Solution Summary

The confidence intervals and the differences between T and Z distributions are examined.

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