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Statistical Analysis and Hypothesis Testing: A Comprehensive Study of t-tests, ANOVA, and Probability Calculations - Document preview page 1

Statistical Analysis and Hypothesis Testing: A Comprehensive Study of t-tests, ANOVA, and Probability Calculations - Page 1

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Statistical Analysis and Hypothesis Testing: A Comprehensive Study of t-tests, ANOVA, and Probability Calculations

This comprehensive study covers various statistical analyses including t-tests and ANOVA methods.

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Statistical Analysis and Hypothesis Testing: A Comprehensive Study of t-tests, ANOVA, and Probability Calculations - Page 1 preview imageStatistical Analysis and Hypothesis Testing: A Comprehensive Study of t-tests, ANOVA,and Probability Calculations1.What is the probability ofrolling a four in the gambling dice game of craps(given two six sided dice)?There are 3 possibilities of rolling a 4 (3+1, 2+2, 1+3) and a total of 36 possible outcomes. Theprobability of rolling a 4 is3/36= 1/12=0.083What is the probabilitythat a player can roll a four 3 times in a row (assume that rolling the dice eachtime does not affect the outcome of the next roll)?.083 x .083 x .083 =0.000582.Population A and Population B both have a mean height of70.0 inches with an SD of 6.0.A randomsample of 30 people is picked from population A, and random sample of 50 peopleis selected fromPopulation B.Which sample mean will probably yield a more accurate estimate of its population mean?Why?SEM(A): 6/SQRT(30)= 1.095SEM(B): 6/SQRT(50)= 0.848Sample B will yield the more accurate population mean because the SEM decreases as thepopulation increases, meaning that we achieve a closer mean of the overall mean.3.Suppose we obtained data on vein size after application of a nitroglycerin ointment in a sample of50patients.Themean vein size is found to be 8.7mm with an SD of 2.1. Using atdistribution table, whatare the confidence limits for a 95% confidence interval? For a 99% confidence interval?SEM 2.1/SQRT(50) = 0.2969SEM = .296995%99%T-dist.2.012.66CI8.7mm +/-(2.01 X 0.2969)8.7mm +/-(2.66 X 0.2969)UCL= 9.29mm, LCL=8.10mmUCL = 9.49mm, LCL =7.91mm4.In a pilot study evaluating the use of a new drug to lower resting heart rates (HR) of patients, thefollowing data was recorded:Subject#RestingHR001720028800371004870056400677007790085900966
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Statistical Analysis and Hypothesis Testing: A Comprehensive Study of t-tests, ANOVA, and Probability Calculations - Page 2 preview image
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Statistical Analysis and Hypothesis Testing: A Comprehensive Study of t-tests, ANOVA, and Probability Calculations - Page 3 preview image0106801178012890139101481015770167501769Given that the average resting HR of the general population for this study is 72, useStatCrunchtoperform the appropriatettest.a)What is the value oft?The Null hypothesis states that the mean of the sample is 72 with the only difference being arandom variation. The alternative hypothesis states that the mean of the sample is NOT 72 anddid not occur in a random way.The calculated t-statistics is1.75The critical table value for t is2.12b)Using an alpha of 0.05, is thetstatistic significant?Why?My calculated t-statistic is less than the table critical value of 2.12. The results are not statisticallysignificant because the t value is smaller than the critical table value of t. Also, the p-value isgreater than the alpha value of 0.05. Therefore, we fail to reject the null hypothesis because theresults probably did occur by chance.c)What are the confidence limits for a 95% confidence interval here and what do they mean for thispatient group?Copy and Paste your work fromStatCrunchinto your Word document submission.The confidence limits for a 95% confidence interval are: 71.15 < x < 80.73. This is,withoutconsidering the population mean of 72,as indicated in the problem. This means that we are 95percent confident that the interval from 71.15 and 80.73 does contain the true value of thepopulation mean.Hypothesis test results:μ: Mean of variableH0:μ= 72HA:μ72VariableSample MeanStd. Err.DFT-StatP-valueHR75.9411762.2581073161.74534510.100195% confidence interval results:μ: Mean of variableVariableSample MeanStd. Err.DFL. LimitU. LimitHR75.9411762.25810731671.15420380.728155.Write one or two sentences that could be used to report the results obtained for the t-test in Exercise4.The experiment in Exercise 4 ended up being not statistically significant. According to the nullhypothesis the mean of the population equals to 72 and the results occurred in a random way. Onthe other hand, the alternative hypothesis tells us that the mean of the population is not 72 and
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