Statiatics Ch 9: Quiz 1 Review

Proportion parameter symbol

P

Proportion Statistic symbol

P-hat

Mean parameter symbol

u

Mean statistic symbol

X-bar

Population standard deviation symbol

o

Sample standard deviation

Sx

Proportion parameter/statistic formula

x/n

Standard deviation formula

p(p-1)/n (All squared)

Margin of error formula

Z p(p-hat - 1)/n (all squared)

Sample size for margin of error formula

(Z/MOE)(p-hat)(1 - p-hat)

To find the confidence interval of a single population mean, use…

Z-test or T-test

Calculator - confidence interval

STAT ➡TESTS➡A: 1-proZInt➡insert: x, n, c-level

Calculator - Mean for Z-score

STATS➡TESTS➡7:ZInt…➡Data(list: 1, Freq: 1)/Stat➡o, x-bar, c-level

Calculator - Mean t-score

STATS➡TEST➡8:TInt…➡insert: x-bar, sx, n, c-level

When should you use t & Z-test

Z-test: when the o is known

T-test: when the o is unknown