PPT-Hypothesis Testing Chapter 6

Inferential Statistics Making inferences about populations based on samples Chapter Outline HypothesisTesting OneTailed and TwoTailed Hypothesis Tests Decision Errors Decision Errors When the right procedures lead to the wrong decisions. ©2013 Michael J. Rosenfeld. Draft date: 1/14/2013. The sample frame, or sample universe, is the data that our sample is drawn from. In the case of the March, 2000 CPS, the sample universe includes all people residing in the US in March, 2000, who were not living in institutional settings. This sample frame has N members.. Note:. In Chapter 8 we used methods of estimating the value of a parameter.. In this chapter, we are drawing inferences about the parameter by making decisions concerning the value of the parameter. Two Hypothesis:. STAT 250. Dr. Kari Lock Morgan. SECTION 4.3. Significance level (4.3). Statistical conclusions (4.3). p-value and H. 0. If the p-value is small, then a statistic as extreme as that observed would be unlikely if the null hypothesis were true, providing significant evidence against H. +. Probability. Seminar 6. A difficult mock question for mid-term. Plot . the following graph. People . who use Facebook only (but not Twitter) are generally happier than those who use Twitter only (but not Facebook). This . Hypothesis Testing. Test of hypothesis - Test whether a population parameter is less than, equal to, or greater than a specified value.. Remember an inference without a measure of reliability is little more than a guess.. STAT 250. Dr. Kari Lock Morgan. SECTION 4.1. Hypothesis test. . Null and alternative hypotheses. . Statistical significance. Tea and the Immune System. L-. theanine. is an amino acid found in tea. Introduction. Researchers interesting in many types of questions. Earth warming. Medication effect on blood pressure. Seat belts and accidents. Are differences in means of populations and means of samples real, or by chance?. Writing a Hypothesis. Quick Questions. What do we remember about testable questions?. What is a hypothesis?. What do hypotheses have in common with testable questions?. How do we write a hypothesis?. Q. uestion. R. andom guess. Observation. Experiment. Your mom. A . hypothesis is:. A . tentative explanation . for an observation or a scientific problem that can be tested by further investigation. . Sample. , shape, location, and spread. Sample = make sure it's random, handle missing data (mcar, mar, nmar), imputation . methods. NMAR!. . Shape = Is the data skewed, normal, or flat? If normal then we can use statistical analysis for normal . Evaluating Differences and Changes. “Our overall customer satisfaction score increased from 92 percent 3 months ago to 93.5 percent today.” . Did customer satisfaction really increase? Should we celebrate?. A nuclear power plant adjacent to a residential area. STATISTICS FOR BUSINESS. (Hypothesis testing for a single population). A nuclear power plant. adjacent to a residential area. Two . local . residents die . Frances Chumney, PhD CONTENT OUTLINE  Logic of Hypothesis Testing  Error & Alpha  Hypothesis Tests  Effect Size  Statistical Power HYPOTHESIS TESTING 2 HYPOTHESIS TESTING LOGIC OF HYPOT I. Terms, Concepts. A. In general, we do not know the true value of population parameters - they must be estimated. However, we do have hypotheses about what the true values are. B. The major