Since he became the president, did President Trump act with the transparency and the integrity
that you expect from a president?” 675 voters responded the poll and 351 responded “YES.”
Assume that 40% of the U.S. population supports Trump.
a. Define a binary random variable, Y, for supporting Trump (Y=1) vs. not (Y=0).
Calculate the population mean (????????) and variance (????????
) for supporting Trump.
b. Calculate the sample mean ????̅ and the sample standard deviation of ????̅ (????????̅ ) for the poll.
c. Calculate the standard error of ????̅ and construct a 95% confidence interval from the
poll using ????̅ and its sample standard error.
d. Conduct a two-sided hypothesis test at 5% significance level to determine whether
40% of the U.S. population supports Trump. State the null and the alternative
hypotheses, calculate the test statistics and the associated p-value, and conclude. Is
the Fox News survey reliable? Why? Why Not?
e. Suppose that you wanted to design a survey that had a margin of error of at most 1%.
That is: the difference between the upper bound and the lower bound of the
confidence interval should be a maximum of 2 percentage points. For example, for
????̅ = 0.52 you are aiming for the 95 % CI to be [0.51 0.53].
How large should n be if the survey uses simple random sampling?
oups were used (lawyer, physical therapist, cabinetmakers, and system analysts). The results obtained for a sample of 5 individuals from each groups. Using the "ANOVA Output" below, please answer the following questions ( Use the significance level 5%).
Q1. The value of the test statistic is ____________
Q2. The p- value of the test is _________________
Q3. At the 5% significance level, the null hypothesis is rejected if the value of the F statistics is >= _________________
Q4. Interpret the ANOVA result at the 5% significance level. Is there any difference in the job satisfaction among the four occupational groups? Answer either yes or no. Explain the reason of your answer statistically.
Data from a Trucking Company is Southern California were utilized to examine the relationship among total daily travel time (y), miles to traveled (X1), and the number of deliveries (x2). Based on the "Regression Output" below, please answer the following questions.
Q5. The number of sample used in this regression analysis is______________
Q6. What is the value of the coefficient of determination?
Q7. What is the F test statistic value for the regression model significane test?
Q8. What is the predicted travel time for X1 =95, and X2= 6?
Q9. Is X2 (number of deliveries) related to Y (travel time)? Answer either yes or no. Explain the reason of your answer statistically.
ATTACHED ARE GRAPHS