What happens to the t statistic when n becomes larger? t-statistic becomes larger O t-statistic becomes smaller t-statistic does not change not enough information to answer the question

Learn with an example v Samples are drawn from a population with mean 56 and standard deviation 23. Each sample has 8 randomly and independently chosen elements. Find the mean, µz, of the distribution of sample means. Submit

A fitness trainer is interested in investigating whether ethnicity and the first exercise activity that members engage in are dependent. The table below shows the results of the trainer's observation of randomly selected members. Frequencies of Ethnicity and Exercise Activity Weight Machines White Hispanic Black Other Cardio 84 84 68 48 98 97 51 70 O Homogeneity O Independence Free Weights 81 98 69 41 What can be concluded at the α = 0.05 significance level? a. What is the correct statistical test to use? O Goodness-of-Fit Paired t-test b. What are the null and alternative hypotheses? Ho: O Ethnicity and first exercise activity are dependent. O Ethnicity and first exercise activity are independent. O The distribution of first exercise activity is not the same for each ethnicity. O The distribution of first exercise activity is the same for each ethnicity. H₁: O The distribution of first exercise activity is the same for each ethnicity. O Ethnicity and first exercise activity are…

answer multiple choices

The table below shows the mean number of daily errors by air traffic controller trainees during the first two weeks on the job. We want to perform a paired t-test at a = .05 to see if the mean daily errors decreased significantly Trainee T1 T2 T3 T4 T5 T6 T7 Week 1 5.1 3. 12.1 6.2 11.5 7.8 2.2 Week 2 3.2 2.2 8.7 7.7 9.4 7.8 3.1 The test statistic is; O 1.25 O 1.75 O 0.87 O 0.79

Question: There choose one (is/is not) enough evidence to conclude that the mean weight is choose one (more than/less than/ different than) 75 pounds.

☐True ☐False Statisticalpower is about your observed statistic (e.g., z,t). The further away from zero your statistic is, the more powerful your study is.

Gender and Frequency of Status Updates on Facebook The Pew Research Center conducted a survey of randomly sampled American adults, asking them about their use of social networking sites such as Facebook. The table below shows the self-reported frequency of status updates on Facebook by gender. Are frequency of status updates and gender related? chi-square statistic = i p-value = i Conclusion: ĮStatus/Gender Ho- Every day 3 - 5 days/week 1 - 2 days/week Every few weeks Less often Total Male Female Total 42 46 70 77 88 386 59 79 79 151 186 491 130 105 149 Round your answer for the chi-square statistic to one decimal place, and your answer for the p-value to three decimal places. 156 337 877 Table 1 Gender and frequency of status updates on Facebook

Data of variable-A is collected as shown to the right. Is the mean of Variable-A less than 80? State null hypothesis and choose level of significance, a = 0.05. (Use Excel ttest function, provide clear logic and reasoning.) Variable-A Variable-B 78.8 81.9 76.9 78.0 67.8 69.7 68.9 74.7 70.5 70.0 80.0 68.2 63.0 88.7 78.7 86.7 85.4 69.5 87.0 75.1 82.4 71.8 78.2 58.1 76.9 74.8 60.2 93.2 82.6 84.6 67.2 66.5 71.7 77.2 68.9 74.0 69.3 77.7 89.1 78.6 76.3 68.3 74.0 89.0 69.4 82.1 76.3 78.0 66.2 80.3 73.9 82.4 79.1 83.1 80.4 66.4 66.2 67.6 80.9 75.3

How many caffeine drinks per day        Count of how many caffeine drinks per day 3 61 2 54 4 38 1 31 0 27 5 23 6 14 7 5 8 5 10 1 2.5 1 1.5 1 9 1 Grant total  262 Calculate the mean, standard deviation, and variance for the variable “How many caffeine drinks per day”. What is the median and range “How many caffeine drinks per day” Determine the first quartile (Q1), third quartile (Q3), and interquartile range (IQR) for the variable “How many caffeine drinks per day”. Calculate the lower and upper limits using the quartile method to determine if there are any outliers for the variable “How many caffeine drinks per day”. Calculate the lower and upper limits using the standard deviation method to determine if there are any outliers for the variable “How many caffeine drinks per day”.