Utilizing Data To Make Inferences
Course Objective
After completing this course students should be able to:
? Have confidence in gathering and using sample data to discern, understand, and interpret the truth about populations and
processes.
? Think critically about the uses of and conclusions drawn from some of the most important statistical methods.
? Communicate statistical results by reporting their conclusions in writing to the instructor.
Learning Objective For This Assignment
In this course you have learned how to gather data to maximize the chance it is representative, how to utilize both graphical
methods and summary statistics to describe data and how to utilize various techniques to draw conclusions / make inferences. In
this assignment you are going to utilize the traffic flow dataset previously formed to apply the techniques of statistical inference.
You are also asked to communicate your inferences / conclusions in a report.
This assignment is designed for you to:
? Demonstrate your ability to utilize Minitab to create confidence intervals and do hypothesis tests.
? Demonstrate your ability to interpret confidence intervals and hypothesis tests.
? Demonstrate your ability to communicate, in writing, the results of your analysis and associated conclusions.
Assignment
Earlier in the course you gathered data on the traffic flow of cars and trucks during weekday mornings and afternoons at the
intersection of Spring Street and Route 27. The data have already been entered into Excel and are available on Blackboard in the
projects folder. The file name is Spring 2014 Project 1 Data.xlsx . The marketing firm has recalculated the traffic flow necessary to
justify advertising at the intersection. They have now determined that if the average traffic flow is more than 70 vehicles (cars and
trucks) in either the morning or the afternoon then advertising is justified.
Procedures
Utilize Minitab to do the following:
a. Create a confidence for the average traffic flow in the morning. Can we be 95% confident that the average traffic
flow in the morning is greater than 70? Why or why not?
b. Setup and execute a hypothesis test and determine how much evidence there is that the average traffic flow in the
morning is greater than 70.
c. Create a confidence for the average traffic flow in the afternoon. Can we be 95% confident that the average traffic
flow in the afternoon is greater than 70? Why or why not?
d. Setup and execute a hypothesis test and determine how much evidence there is that the average traffic flow in the
morning is greater than 70?
Deliverables
Utilize your results to write a one page memo to your ISA professor stating and supporting your recommendation on
whether or not advertising at this intersection is justified. Your memo should include an attachment containing your
Minitab output.
* Jobe, J. M. (1988). “An Applied Problem in an Introductory Statistics Course”, Proceedings of the American Statistical
Section on Statistical Education.
