By the end of the preschool period, the __________, a bundle of nerve fibers that connect the two hemispheres of the brain, becomes considerably thicker.

For each of the below statements, state if it is true or false.  Type I error in the context of a chi-square test for independence is concluding that there is relationship between two variables when there really is not. This is a [fill1] statement.  If the slope of the regression line is negative, then there is a negative linear relationship between the variables. This is a [fill2] statement.  The absolute value of the correlation coefficient describes the strength of the linear association between X and Y. This is a [fill3] statement.  Correlation between two quantitative random variables X and Y is 0.81. Slope of the least square regression line of Y on X must be positive. This is a [fill4] statement.

Students in an introductory chemistry class participate in a mid-semester survey. They were asked whether having recitation classes better prepare them for the course. Their opinion were coded as “0” if the answer is No, “1” if the answer is somewhat helpful, “2” if the answer is yes. This variable is:  

Use the following five-number summary: Minimum Q1 Median Q3 Maximum 15 36.5 53 72 98 Select the correct statement.

A local candy shop found from the past observation that 25% of the people who enter the shop actually buy something. Four potential customers enter the shop (you may assume they are random). Find the probability of at least one sale to the four customers.  

Accounts department of an airline company claims that 2 out of 10 flights depart from a certain airport are delayed. Suppose you work for the company as a statistical consultant and want to see whether true proportion of delayed flights is different from what they claim. You randomly selected 120 flights and recorded their flight status. Out of 120 sampled flights, 18 flights were delayed. p-value of the test is  

Please note that this question consists of seven parts. Show all your work. You may use Minitab but you need to show the steps to get the answer. Just giving the answer without showing work may result in zero for the question.  A random sample of 300 students is taken and whether the student is in Honor Roll or not and whether the student is a Music student or not are noted. A contingency table of the data is given below. Expected counts are provided within the parentheses. Music Student Honor Roll Student Total Yes No Yes 17 (16.17)   33 (33.83)   50 No 80 (80.83) 170 (169.17) 250 Total 97 203 300   Write the null and alternative hypotheses to test if there is an association between “Music Student” and “Honor Roll Student.” Under the null hypothesis, how many students, who are music student and are in Honor roll, should we expect to see? Show your calculation to get this. Calculate the test statistic for the test you set up in part 1. You may use MINITAB to get the value of final test statistic. However, you need to show the mathematical calculation that resulted in the final answer.  Under the null hypothesis, what is the distribution of the test statistic? What is the degrees of freedom of the test statistic? Calculate the p-value for the test you formulate in part 1. Write the p value as a probability statement and then use may use software (MINITAB) or provided tables to find the numerical value of the p value.  Write the final conclusion in the context of the problem (use 5% significance level). From the methods you learnt in this class, suggest another test that would answer the same research question.     

How is nature represented in Shinto?

When historians look at Japan’s religious history, which tradition is Shinto most closely compared and tied to?

A nurse is assessing a newborn and observes bluish-gray discoloration over the sacral area consistent with congenital dermal melanocytosis (Mongolian spots). Which action should the nurse take?