A survey published in the American Journal of Sports Medicine2 reported the number of meters (m) per week swum by two groups of swimmersthose who competed exclusively in breaststroke and those who competed in the individual medley (which includes breaststroke). The number of meters per week practicing the breaststroke was recorded for each swimmer, and the summary statistics are given below. Is there sufficient evidence to indicate that the average number of meters per week spent practicing breaststroke is greater for exclusive breaststrokers than it is for those swimming individual medley? Specialty Exclusively Breaststroke Individual Medley Sample size 130 80 Sample mean (m) 9017 5853 Sample standard deviation (m) 7162 1961 Population mean 1 2 a State the null and alternative hypotheses. b What is the appropriate rejection region for an = .01 level test? c Calculate the observed value of the appropriate test statistic. d What is your conclusion? e What is a practical reason for the conclusion you reached in part (d)?
Chapter 4 Elementary Probability Theory Material Extracted From Textbook (Brase, Charles Henry., and Corrinne Pellillo. Brase. Understandable Statistics: Concepts and Methods . 11th ed. N.p.: Cengage Learning, n.d. Print.) 4.1 What is Probability Probability is a numerical measure between 0 and 1 that describes the likelihood that an event will occur. Probabilities closer to 1 indicate that the event is more likely to occur. Probabilities closer to 0 indicate that the event is less likely to occur. Probability Assignments 1. A probability assignment based on intuition incorporates past experience, judgement, or opinion