1. What is a t-distribution? 2. When is a z-test and the t-test used?
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Q: B AND C ONLY
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Q: p9 need help please with B and C. Thanks
A: The data shows the time that they spend in the shower of poor and rich.
B. Explain the following:
1. What is a t-distribution?
2. When is a z-test and the t-test used?
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Solved in 4 steps
- Please help with answers for a, b and c.Is the distribution of marital categories in the GSS representative of their distributions in the population? Let’s assume that in the U.S.: married = 48%, widowed = 6%, divorced = 12%, separated = 2%, never married = 32%. In the 2018 GSS, MARITAL is coded: 1=married, 2=widowed, 3=divorced, 4=separated, and 5=never married. Interpret the output and provide the output from this test as a part of your answer. Discuss your interpretation of the results using APA format. 1.) Assumption? 2.) Level of measurement? 3.) Null hypothesis? 4.) Research hypothesis? 5.) Select the sampling distribution and establish the critical region? 6.) Compute the test statistics? 7.) Interpret the results using APA format? *Use the graphs inserted below in images.Examine the normal quartile plot and determine whether it depicts sample data from a population with a normal distribution Does the normal quantile plot depict sample data from a population with a normal distribution? A. No. The points do not lie close to a straight lineB. Yes. The points are evenly distributed above and below the mean, 0C. The points exhibit some systematic pattern that is not a straight-line patternd. Yes. The pattern of the points is reasonable close to a straight line.
- What are the values for SS and variance for the following sample of n = 3 scores? Sample: 8, 5, 2Each of the boxplots shown summarizes 24 student scores on a recent test in two different classes. The boxplots are drawn using a common numerical scale. Which of the following must be true? 1. The lower 25% of Class B are much more spread out than the lower 25% of Class A 2. More people scored below the lower quartile for Class A than Class B 3. The distribution for Class B is skewed left and has a noticeable outlier as well, while the distribution for Class A is somewhat skewed right 4.Class A had more people between the median and the lower quartile than Class B. 3.The distribution for Class A is somewhat symmetric, while the distribution for Class B is skewed right with a noticeable outlier as wellA researcher wanted to determine if carpeted or uncarpeted rooms contain more bacteria. The table shows the results for the number of bacteria per cubic foot for both types of rooms. A normal probability plot and boxplot indicate that the data are approximately normally distributed with no outliers. Do carpeted rooms have more bacteria than uncarpeted rooms at the a = 0.01 level of significance? Full data set O Carpeted 14.3 9.8 10.7 12.2 Uncarpeted 9.5 9.5 10.9 2.1 15 3 15.8 5.4 6.4 15.2 4.3 10.6 - X Student t-distribution Area in right tail t-Distribution Area in Right Tail Degrees of Freedom 0.25 0.20 0.15 0.10 0.05 0.025 0.02 0.01 0.005 0.0025 0.001 0.0005 1.000 0.816 0.765 0.741 1.376 1.061 0.978 0.941 0.920 1.963 1.386 1.250 1.190 1.156 3.078 1.886 1.638 1.533 6.314 2.920 2.353 2.132 12.706 4.303 3.182 2.776 2.571 15.894 4.849 3.482 2.999 2.757 31.821 6.965 4.541 3.747 3.365 63.657 9.925 5.841 4.604 4.032 127.32 1 14.089 7453 5.598 318.309 636.619 31.599 12.924 8.610 6.869 22.327…
- A researcher has run an experiment on the effects of early cognitive simulation on children and their school success at age 10 years. He wants to compare his sample results to the normal distribution (z-distribution), but he is not sure whether the population distribution is normal or not. He comes to you as an expert in statistics for advice. Can he do this? Why or why not? What conditions must be met?1. We want to investigate whether traffic accidents are more likely on certain days of the week on certain road sections. Which of the following tests best fits the situation?Choose one:a. Two-way analysis of variance OR b. Compatibility test OR c. Paired t-test 2. In which of the following can it be assumed that the sample comes from a normal distribution?Choose one:a. In the Runs test (random test)b. In the compatibility testc. In a two-way analysis of varianceThe type of household for the U.S. population and for a random sample of 411 households from a community in Montana are shown below. Observed Number of Households in the Community Percent of U.S. Type of Household Households Married with children 26% 110 Married, no children Single parent One person Other (e.g., roommates, siblings) 29% 101 32 25% 98 11% 70 Use a 5% level of significance to test the claim that the distribution of U.S. households fits the Dove Creek distribution. (a) What is the level of significance? State the nul and alternate hypotheses. O Ho: The distributions are different. H: The distributions are the same. O Hg: The distributions are the same. H: The distributions are different. O Hg: The distributions are the same. H: The distributions are the same. O Hg: The distributions are different. H: The distributions are different. (b) Find the value of the chi-square statistic for the sample. (Round the expected frequencies to two decimal places. Round the test…
- a.What decision can you make? b. What does that decision mean? c. What type of error could you be making, and what would it mean?A researcher believe that increasing attention given to children will improve academic performance. He invites parents to volunteer during school to help the children with their activities. At the end of the school year he compares the academic performance of these children with the mean and standard deviation of historical rate on academic achievement. Which statistic test is appropriate for this study and why? (By using the decision tree). A. Z test B. Single sample t test C. Two independent samples t test D. Two related samples t test E. One way between subjects ANOVA F. CorrelationThe average retirement age in America is 62 years old. Do small business owners retire at an older average age? The data below shows the results of a survey of small business owners who have recently retired. Assume that the distribution of the population is normal. 73, 55, 72, 67, 56, 66, 56, 55, 74, 65, 62, 72, 75 What can be concluded at the the a = 0.01 level of significance level of significance? a. For this study, we should use Select an answer b. The null and alternative hypotheses would be: Ho ? ◇ Select an answer H₁: ? ✨ Select an answer ✰ c. The test statistic? = your answer to 3 decimal places.) d. The p-value = to 4 decimal places.) e. The p-value is ? ✨ a (please show (Please show your answer f. Based on this, we should Select an answer the null hypothesis. g. Thus, the final conclusion is that ... O The data suggest the population mean is not significantly older than 62 at a = 0.01, so there is sufficient evidence to conclude that the population mean retirement age for…