4. An experimental study was conducted in the effect of programmed materials in English on the performance of 20 selected college students. Before the program was implemented the pretest was administered and after 5 months the same instrument was used to get the test result. The following is the result of the experiment. Pretest Posttest X1 X2 20 25 30 35 10 25 15 25 20 20 10 20 18 22 14 20 15 20 20 15 18 30 15 10 15 16 20 25 18 10 40 45 10 15 10 10 12 18 20 25

4. An experimental study was conducted in the effect of programmed materials in English on the performance of 20 selected college students. Before the program was implemented the pretest was administered and after 5 months the same instrument was used to get the test result. The following is the result of the experiment. Pretest Posttest X1 X2 20 25 30 35 10 25 15 25 20 20 10 20 18 22 14 20 15 20 20 15 18 30 15 10 15 16 20 25 18 10 40 45 10 15 10 10 12 18 20 25

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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A graduate student is interested in how viewing different types of scenes affects working memory. For his study, he selects a random sample of 36 adults. The subjects complete a series of working memory tests before and after walking in an urban setting. Before the walk, the mean score on the test of working memory was 9.1. After the walk, the mean score was 1.4 higher. The graduate student has no presupposed assumptions about how viewing different types of scenes affects working memory, so he formulates the null and alternative hypotheses as: H00 : μDD = 0 H11 : μDD ≠ 0 Assume that the data satisfy all of the required assumptions for a repeated-measures t test. The graduate student calculates the following statistics for his hypothesis test: Mean difference (MDD) 1.4 Estimated population standard deviation of the differences (s) 1.6 Estimated standard error of the mean differences (sMDMD) 0.2667 Degrees of freedom (df) 35 The t statistic 5.25 The critical values of t…
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determine the degrees of freedom if necessary
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There are many ways to measure the reading ability of children. Research designed toimprove reading performance is dependent on good measures of the outcome. Onefrequently used test is the DRP, or Degree of Reading Power. A researcher suspects that themean score µ of all third- graders in Henrico County Schools is different from the nationalmean, which is 32. To test her suspicion, she administers the DRP to an SRS of 44 HenricoCounty third-grade students. The distribution of scores is summarized in the Minitab outputbelow: MEAN STDEV SEMEAN MIN Q1 MEDIAN Q3MAXDRP 35.09 11.19 1.69 14.00 26.00 35.00 44.0054.00 Construct a 90% confidence interval to estimate the mean DRP score in Henrico CountySchools.
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You are interested in investigating the efficacy of a new pain medication and design an experiment measuring pain levels before and after the administration of a new medication. You recruit 9 people to participate in your study and bring the same 9 participants in for two separate sessions. Here is the raw data: Pair Number Placebo Pain Score Pain Medication Pain Score 1 2 4 5 6 7 8 9 5 7 10 5 8 7 8 6 8 QUESTION 20 5 5 8 4 4 3 5 3 2 Use the t-test handout printout provided to calculate the t- statistic. What is the t-test statistic value? Round to the nearest tenth. What conclusion would you make on the above data, based on the t-value you calculated and the critical value of t? O You accept the null hypothesis because the t-value you calculated is inside the bounds of the critical t-value O You reject the null hypothesis because the t-value you calculated is inside the bounds of the critical t-value O You reject the null hypothesis because the t-value you calculated is outside the…