Using Lists & Spreadsheet 231
2-Prop z Interval (zInterval_2Prop)
2-Prop z Interval (two-proportion z confidence interval) computes a
confidence interval for the difference between the proportion of
successes in two populations (p
1
-p
2
). It takes as input the count of
successes in each sample (
x
1
and x
2
) and the count of observations in each
sample (n
1
and n
2
). The computed confidence interval depends on the
user-specified confidence level.
This test is useful in determining if two rates of success differ because of
something other than sampling error and standard deviation. For
example, a bettor could use this test to determine if there is an
advantage in the long run by playing one game or machine versus
playing another game or machine.
Linear Reg t Intervals (LinRegtIntervals)
Linear Reg t Intervals computes a linear regression t confidence interval
for the slope coefficient b. If the confidence interval contains 0, this is
insufficient evidence to indicate that the data exhibits a linear
relationship.
Multiple Reg Intervals (MultRegIntervals)
Computes multiple regression prediction confidence interval for the
calculated y and a confidence for y.