DS 101 NAME ______
EXAM #1
Fall 2008 DISK # ______
DIRECTIONS: There is a time limit of 70 minutes for this exam. Make sure you have written down your flash drive number on the exam above. Answer all of the questions in the space provided, using the backside, if necessary. SHOW ALL OF YOUR WORK (THOUGHT PROCESS). Answers alone are not sufficient. You need to provide the justification for your answers. If you have problems with the computer, let the instructor know.
The data for problems 1 and 2 can be found at S:/TAYLOR/STKS.XLS
1. ( 15 points) There are two stocks listed in STKS.XLS. Walt Disney (DIS) and General Motors (GM). Based upon their rate of returns (Xt - Xt-1 ) / Xt-1 which stock is riskier? Why?
2. (15 points) Does GM follow a random walk?
H0 :
HA:
3. (15 pts) The underlying principle of all statistical inference is one the uses sample statistics to learn something (that is to infer) about parameters. Convince me that you understand this statement by writing a short paragraph describing a situation in which you might use a sample statistic to infer something about a population parameter. Clearly identify the sample, population, statistic and parameter in you example. Be as specific as possible, and do not use any example which we have discussed in class.
4. (20 points) Shown below is the sales values, per week, for Krazy Corn Cereal under different conditions regarding the shape of the container. The placement of the cereal remains the same ( medium shelf height) and the color\design remains the same throughout the experiment.
SQUARE CIRCLE PENTAGON
234 255 212
244 265 223
232 256 233
199 266 233
233 244
244 234
245
Determine if there is a significant effect due to the shape of the container. If you determine there is an effect, state what the effect represents. State any assumptions you make.
Ho:
HA:
The data for problem 4 is located at S:/TAYLORS/ALMONDS.SF6
5. (20 points) You have been assigned the task of monitoring quality control for the Blue production line at the BC Almond plant. . Each of the following series contains a set of consecutive observations. Using an appropriate control chart determine if the series are in statistical control (i.e. does specific variation exist ?)
a) BC.one
b) BC.two
c) BC.three
d) BC.four
6. . (15 pts) ) You have been given the task of analyzing the results of a recently completed survey by FSO Research in which they are seeking information that can be used by a newspaper, The Bee. The results from the survey are coded in the file FSO.SF6 for the following questions
What is your age?
____ < 20 ____ 20 - 30 ____ 31 - 40 ___ >40
What paper do you read most of the time?
_____ Chronicle ____ Union _____ BEE ___ OTHER
What is your gender?
_____ Male _____ Female
where the first response for each question is recorded as a 1, the second as a 2, ......
Which variables are not related? Which variables are related? For those that are related, explain how are they related?
END OF EXAM
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