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Find the critical tvalue that corresponds to 80% confidence with 24 degrees of freedom.
alpha = 0.2, so t_alpha/2 = t_alpha/2 = t_0.2/2 = t_0.10
TI84: Stats > Tests > option 4
OR
PRGRM > Area Left = .9 > DF > 24
Same as invNorm function, but for samples, not populations.

Name the two tinterval construction requirements:
1) Normal probability plot suggests a normal population based in ctirical values of the correlation coefficient vs. correlation coefficient.
2) No outliers in boxplot

In confidence intervals...
if sample size is < 30, what conditions must be satisfied to compute the Confidence Interval?
Sample data must come from a population that is normally distributed with no outliers.

Confidence Interval requirements are:
1) SRS
2) n<0.05N

Confidence Interval for Population Mean:
where
TI84:
Use Stat > Tests > option 4
OR
PRGRM, where n1 = degrees of freedom
Use formula above after using calc to find value

Confidence Interval for Population Parameter:
Use Stat > Tests > Option 8 (Ttest)

Sample size is asked for:
For "E", do not use decimal points in this formula. Use the value given for "points".

For Confidence Intervals for standard deviation when s^{2} is given, do NOT use the square root part of the function, just the formula inside the square root.

Know Reasoning Questions (e.g., What happens to a confidence interval if you increase the sample size?)

Use 1PropZtest on TI84 for __________ _____ for proportions.
Requirements to construct a hypothesis tests are three:
hypothesis tests
 1) SRS
 2) np(1p)>=10
 3) n<0.05N

n ____ increase by a factor of _ to ________ E by a factor of ___.
must, 9, decrease, 1/3

Define "Margin of Error"
the amount the estimate based on the sample data could be away from the true percentage with a certain level of confidence.
This is HALF the width of the confidence interval.

Define "Critical Value":
number of standard errors to move from the mean of a sampling distribution to correspond to a specified level of confidence.

Use in place of
to find "n" for a proportion when IS GIVEN.

For confidence interval estimates for the population mean , use...
Requirements:
 1) SRS
 2) n>=30 or approximately normally distributed
TI84: Use TInterval (Stat, Tests, Option 8)

