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IT-223 - Assignment #1

All questions in this assignment should be saved into a Microsoft Word document or any ‘doc’ or ‘RTF’ compatible file.  PDF is also fine. This file will then be submitted to COL.

This assignment is a combination of theoretical questions along with a few 'numbers' questions. All answers including graphs should be in a standard word processing document (Microsoft Word, Google Document).You will submit this file as an attachment to COL. The values in brackets are max points for each question.

Graphs:  You will be asked to draw a few graphs for this assignment. In order to submit, you will have to scan those graphs into your Word document.  If you don't have access to a scanner, you may need to run out to Kinkos or similar to get it in. However, I expect that this will be the only time in the course where you will need to scan anything.  If you absolutely can not get to a scanner (e.g. a DL student who lives in the middle of nowhere), let me know and we can discuss other options. A clever technique used by one student was simply to photograph his graphs using a digital camera/phone etc and paste from their into the document.

Question #1 (10):  American Airlines flight 91 from London to Chicago O'Hare is scheduled to arrive at 7:50 PM.  Not surprisingly, several flights arrive several (or many!) minutes early, and several flights arrive late. The following flight times were recorded over a 6-day sequence (all times are PM):  8:05, 7:49, 8:43, 7:50, 11:47,  7:31.

Give the 5-number summary and draw a box plot (use the modified box plot if there are any outliers).

On average (i.e. using the mean) how many minutes early or late does this flight tend to arrive?  Is the mean an ideal statistic for determining the center of this distribution? (Hint: Is there an outlier? How would you decide?) Show your calculations.

Question #2 (9): The following table gives the survival times in days of several guinea pigs after they were injected with tubercle bacilli in a medical experiment.

41,99,103,103,105,107,111,113,114,117,119,598

·         (3) Draw a histogram (pick what you think is an ideal bin-size).  Draw what you think is a good density curve over the historgram.

·         (3) Then describe the distribution of survival times. Are there any outliers?

·         (3) Summarize the distribution by giving the five-number summary and by drawing a modified box-plot.

BONUS VERSION - Worth up to 5 additional points: Use this dataset instead:

66 123 126 43 53 167 56 139 58 57 118  113 109 162 147 203 102 80 162 329 81 81 598 81 82 145 156 90 73 45 100 81 89 102 97 156

Question #3 (6): This is not a stats question… Read the article at the top of the class web page called ‘Curve of Forgetting’.  Summarize the article. Your summary does not have to be long, but it does need to demonstrate that you read and understood the article.

Question #4 (8):  The following dataset comes from a series of student scores on a standardized exam:  687, 692, 681, 598, 789, 763, 990, 490.  Calculate the mean and median.

Question #5 (7): This is not a statistics question, and  is meant to be some easy points.  Next lecture, we will begin using a very powerful (and expensive!) statistical software package called SPSS.  DePaul has a special license that allows us to remotely use SPSS that has been installed on DePaul machines. To do this, however, you need to set up remote desktop.  This in of itself is not very difficult, but may take a little bit of playing around.  All you have to do for this question, is go through the steps and demonstrate that you have successfully connected to SPSS. Begin by going to the ‘Resources’ page and, go through the steps needed to start SPSS using remote desktop. Once SPSS has been started, paste in a screenshot  to show that you successfully got it started. This will give you full points for the question.  One way to get the screenshot into your document  is to press the ‘PrintScreen’ button on your keyboard, then open your Word document and press control-V.

Submit your assignment to COL. As will always be the case, it is due 10 minutes before class time.