A company selling licenses for new e-commerce computer software advertises that firms using this software obtain, on average during the first year, a yield of 10% on their initial investments. A random sample of 10 of these franchises produced the following yields for the first year of operation:6.1 9.2 11.5 8.6 12.1 3.9 8.4 10.1 9.4 8.9Assuming that population yields are normally distributed, test the company’s claim.

The number of times a machine broke down each week was observed over a period of 100 weeks and recorded in the accompanying table. It was found that the average number of breakdowns per week over this period was 2.1. Test the null hypothesis that the population distribution of breakdown is Poisson.Number of breakdowns 0     1    2    3    4    5 or moreNumber of weeks          10  24   3 2 23   6     5

A sample of 26 offshore oil workers took part in a simulated escape exercise, resulting in the accompanying data on time (sec) to complete the escape. 389 356 359 363 375 425 326 395 402 373 373 370 365 367 364 325 339 393 392 369 375 359 357 404 335 398   A normal probability plot of the n = 26 observations on escape time given above shows a substantial linear pattern; the sample mean and sample standard deviation are 371.08 and 24.41, respectively. (Round your answers to two decimal places.) (a) Calculate an upper confidence bound for population mean escape time using a confidence level of 95%.   (b) Calculate an upper prediction bound for the escape time of a single additional worker using a prediction level of 95%.   c) Suppose that two additional workers will be chosen to participate in the simulated escape exercise. Denote their escape times by X27 and X28, and let Xnew denote the average of these two values. Modify the formula for a PI for a single x value to…

Childhood participation in sports, cultural groups, and youth groups appears to be related to improved self-esteem for adolescents (McGee, Williams, Howden-Chapman, Martin, & Kawachi, 2006). In a representative study, a sample of n = 100 adolescents with a history of group participation is given a stan- dardized self-esteem questionnaire. For the general population of adolescents, scores on this questionnaire form a normal distribution with a mean of p %3D 50 and %3D 15. The sample of group- a standard deviation of o %3D participation adolescents had an average of M = 53.8.

Rothamsted Experimental Station (England) has studied wheat production since 1852. Each year many small plots of equal size but different soil/fertilizer conditions are planted with wheat. At the end of the growing season, the yield (in pounds) of the wheat on the plot is measured. Suppose for a random sample of years, one plot gave the following annual wheat production (in pounds):  3.06 4.97 5.01 4.13 5.02 2.91 3.88 2.55 2.91 5.18 3.68 4.54 2.65 4.14 5.11 3.19 Use a calculator to verify that the sample variance for this plot is s^2=0.923. Another random sample of years for a second plot gave the following annual wheat production (in pounds):  3.61 3.50 3.81 3.89 3.84 3.50 3.53 3.62 3.67 4.05 3.82 4.12 3.75 3.92 4.05 4.01 Use a calculator to verify that the sample variance for this plot is s^2=0.042. Suppose that we test the claim using a=0.01 that the population variance of annual wheat production for the…

TRUE OR FALSE

what is the p value? is the p-value low? can we conclude?

Two samples of n = 5 participants each generate the following data.  Calculate a t-test score for the difference of these two groups. Group 1 Group 2 2 3 3 3 2 2 2 2 1 2     t(8) = 2.86     t(8) = 2.29     t(8) = 2.5     t(8) = 1.11

A recipe submitted to a magazine by one of its subscribers states that the mean baking time for a cheesecake is 57 minutes. A test kitchen preparing the recipe before it is published in the magazine makes the cheesecake 12 times at different times of the day in different ovens. The following baking times (in minutes) are observed. 52 54 55 57 60 63 64 64 66 64 65 66 Assume that the baking times belong to a normal population. (a) Test the null hypothesis that the mean baking time is 57 minutes against the alternative hypothesis 57. Use a=.05. (b) What is the P value?

The following three independent random samples are obtained from three normally distributed populations with equal variance. The dependent variable is starting hourly wage, and the groups are the types of position (internship, co-op, work study). Group 2: Co-op Group 3: Work Study Group 1: Internship 10 10.5 11.25 11 9.25 10.25 9.75 13.25 10.5 12.5 10.5 10.75 Use technology to conduct a one-factor ANOVA to determine if the group means are equal using a = 0.01. Group means (report to 2 decimal places): Group 1: Internship: Group 2: Co-op: Group 3: Work Study: ANOVA summary statistics: F-ratio = (report accurate to 3 decimal places) 12.25 10.5 10.75 11.5 10 10.5 р (report accurate to 4 decimal places) Conclusion: © The sample data suggest the average starting hourly wages are not the same. O There is not sufficient data to conclude the starting wages are different for the different groups.