Concept explainers
Statistical Significance and Practical Significance. In Exercises 13-16, determine whether the results appear to have statistical significance, and also determine whether the results appear to have practical significance.
16. IQ Scores Most people have IQ scores between 70 and 130. For $32, you can purchase a computer program from Highiqpro.com that is claimed to increase your IQ score by 10 to 20 points. The program claims to be “the only proven IQ increasing software in the brain training market,” but the author of your text could find no data supporting that claim, so let’s suppose that these results were obtained: In a study of 12 subjects using the program, the average increase in IQ score is 3 IQ points. There is a 25% chance of getting such results if the program has no effect.
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Essentials of Statistics, Books a la Carte Edition (5th Edition)
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