PPT-Hypothesis Testing with

t Tests Arlo Clark Foos What have we done so far alpha levels cutoffs pvalue Onetailed vs Twotailed tests Goal Estimate likelihood of obtaining sample mean given some known population parameters . Statistics. Terms. Null hypothesis. – The claim being assessed in a hypothesis test is called the null hypothesis. . Usually, the null hypothesis is a statement of “no change from the traditional value,” “no effect,” “no difference,” or “no relationship.” . 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. Mr. Mark Anthony Garcia, M.S.. Mathematics Department. De La Salle University. Situation: Hypothesis Testing. Suppose that a political analyst predicted that senatorial candidate A will top the upcoming senatorial elections in city X with at least 0.70 or 70% of the votes.. Ho - this hypothesis holds that if the data deviate from the norm in any way, that deviation is due strictly to chance.. Alternative hypothesis. Ha - the data show something important.. Doing decision = accept/reject Ho (the decision centers around null hypothesis). 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.. What is hypothesis testing?. A statistical hypothesis is an assumption about a population parameter. This assumption may or may not be true. . The best way to determine whether a statistical hypothesis is true would be to examine the entire population. Since that is often impractical, researchers typically examine a random sample from the population. . Chong Ho Yu (Alex). Ford's Model T in Statistics. Most statistical procedures that we still use today were invented in the late 19. th. century or early 20. th. century.. The t-test was introduced by William Gosset in 1908.. Hypothesis Testing. A statement has been made. We must decide whether to . b. elieve it (or not). Our belief decision must ultimately stand on three legs:. What does our general background knowledge and experience tell us (for example, what is the reputation of the speaker)?. 5th - 9th December 2011, Rome. A hypothesis. Is the prevalence within each food consumption group significantly different between male-headed and female-headed households?. Both variables are categorical… . 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. . 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. . 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?. Type I & II Error and Test of 1 &2 Tailed Hypothesis Khagendra Kumar Dept. of Education Patna University Decision Making on Accepting & Rejecting Hypotheses  To take decision for accepting or 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