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Test 3 Review Vocabulary and symbolic notation: Point estimate of the population mean of a statistic used to estimate the value of a parameter. Confidence interval- is an interval of numbers obtained from a point estimate and a percentage that specifies how confident we are that a parameter lies in an interval. Confidence level-confidence percentage Margin of Error (E) T-distribution, degrees of freedom Assumptions for Confidence Intervals: Point estimate of the population mean value of a statistic used to estimate the parameter. Normal populations or large samples. All samples are simple random samples Chapter 8 Know that X is a point estimate of Know how to compute (1 ) 100% Confidence Interval for Remember our assumptions for CI Normal populations or large samples. All samples are simple random samples 1. When is known (Z-interval) 2. When is unknown (T-interval) Interpret the Confidence Interval What is the margin of error for a given, CI, know how it changes with increased sample size. Also know how the confidence level affects the Confidence Interval. Estimate the sample size for given E and confidence level. Chapter 9 1. Know new vocabulary and symbolic notation: Null and alternative hypotheses Two - tailed, left-tailed, right-tailed alternative hypothesis rejection region, critical value(s) test statistics significance level of the test ( ) p-value Type I and II errors 2. Remember our assumptions for Hypothesis tests: Normal populations or large samples. All samples are simple random samples Sigma is or is not known. One Mean z-test Know how to test Ho: = 0 versus appropriate alternative hypothesis Known population standard deviation Know how to compute the test statistic, Know how to interpret hypothesis test for 0 One Mean t-test Know how to test Ho: = 0 versus appropriate alternative hypothesis Calculated sample standard deviation Know how to compute and interpret CI for 0 Chapter 10 1. Non-pooled t-test: Know how to test Ho: 1 2 versus appropriate alternative hypothesis (for independent samples) Unknown population standard deviations (not assumed equal) (2 samples approximate t- test, use df=estimated by formula) Know how to compute and interpret CI for 1 2 (non-pooled case only) Know connection between two-(tailed) sided hypothesis test and confidence interval for 1 2 If CI contains 0, we can't reject Ho: 1 2 for two tailed test (at the given ) 2. Paired data t-test: Know how to test Ho: 1 2 versus appropriate alternative hypothesis (for dependent samples) Standard deviation for paired data (2 samples approximate t- test, use df=number of pairs - 1) Know how to compute and interpret CI for 1 2 Know connection between two-(tailed) sided hypothesis test and confidence interval for 1 2 If CI contains 0, we can't reject Ho: 1 2 for two tailed test (at the given )