Introduction to statistics final exam

STAT 200: Introduction to Statistics Final Examination, Fall 2017 OL4

STAT 200 OL4/US2 Sections Final Exam
Fall 2017

The final exam will be posted at 12:01 am on December 15, and it is due at 11:59 pm on December 17, 2017. Eastern Time is our reference time.

This is an open-book exam. You may refer to your text and other course materials for the current course as you work on the exam, and you may use a calculator. You must complete the exam individually. Neither collaboration nor consultation with others is allowed. It is a violation of the UMUC Academic Dishonesty and Plagiarism policy to use unauthorized materials or work from others.

Answer all 20 questions. Make sure your answers are as complete as possible. Show all of your supporting work and reasoning. Answers that come straight from calculators, programs or software packages without any explanation will not be accepted. If you need to use technology (for example, Excel, online or hand- held calculators, statistical packages) to aid in your calculation, you must cite the sources and explain how you get the results. You can only submit the Word doc answer sheet. Final Exam answer sheets must be uploaded before the deadline as they will not be accepted via email.

Record your answers and work on the separate Word doc answer sheet provided.

This exam has 20 questions; 5% for each question.

You must include the Honor Pledge on the title page of your submitted final exam. Exams submitted without the Honor Pledge will not be accepted.

STAT 200: Introduction to Statistics Final Examination, Fall 2017 OL4

1.

True or False. Justify for full credit.

(a) If A and B are disjoint, P(A) = 0.4 and P(B) = 0.5, then P(A OR B) = 0.9.

(b) If the variance for a data set is zero, then all the observations in this data set must be
identical.

(c) There may be more than one mode in a data set.

(d) A 90% confidence interval is wider than a 95% confidence interval of the same parameter.

(e) In a right-tailed test, the value of the test statistic is 2. The test statistic follows a
distribution with the distribution curve shown below. If we know the shaded area is 0.03, then we have sufficient evidence to reject the null hypothesis at 0.05 level of significance.

Choose the best answer. Justify for full credit.

UMUC STAT Club wanted to estimate the study hours of STAT 200 students. One STAT 200 section was randomly selected and all students from that section were asked to fill out the questionnaire. This type of sampling is called:

2.

(a)

(b)

A study was conducted at a local college to analyze the trend of average GPA of all students graduated from the college. According to the Registrar, the average GPA for students with economics major from the class of 2016 is 3.5. The value 3.5 is a

(i) statistic

(ii) parameter

(iii) cannot be determined