Computer Exercises: Estimation
(This exercise was give to work with Microsoft Excel and
SPSS. It may be modified to work with other programs, and it
may have to be modified to work with the current version of
Excel and SPSS.)
How old do you think people on average when they die
_______? (Fill in a number before you do anything else.)
Every week important people die, and obituaries are
written about them. Several years ago 30 people who died had
obits written about them in one of the issues of the Sunday
Chicago Tribune. Here were their ages:
89.00 90.00 66.00 39.00 55.00
81.00 101.00 79.00 44.00 65.00
67.00 96.00 72.00 69.00 100.00
71.00 72.00 83.00 63.00 84.00
91.00 81.00 77.00 82.00 72.00
83.00 86.00 86.00 36.00 71.00
1. Enter these data into Excel and compute the mean
__________, median __________, mode __________, range
__________, and standard deviation __________. Save your
results.
2. It is time to meet SPSS. Open the program, and see if
you can open your Excel data into it. If not, retype it. You
should have a column with 30 numbers. Click on the top of
the column (which says var) and give your column a name
(like age).
2. Once you have your 30 numbers, you can compute stuff.
Pull down Statistics to Summarize to Descriptives. Move your
variable over to the variable side (Highlight it, and then
click the arrow). Hit Options and click on all the fun
things you want to see. Hit Continue then OK. You will then
see mean __________, and standard deviation __________.
3. Let's try some more. Pull down Statistics to Summarize
to Frequencies. Move Age to the variable window, then click
the statistics button. Click whatever you want, then click
continue. The click the Charts button. Turn on the radio
button for histogram and click on the "With Normal curve."
Click continue, and then click OK. Are you impressed yet?
4. (Looking aheadstatistical inference). Pull down
Statistics to "Compare Means" to "One Sample T Test." Enter
the number from the top of this sheet (your guess as to the
average age of death) in the test Value. Then hit OK. You
will have no clue as to what these results mean, but you
will once you understand hypothesis testing!!!
(Other sources of data that I used for course assignments on
estimation and hypothesis testing were taken from Ebay,
Facebook, and survey results that I was given. Trying to get
what was cleary random samples from Ebay and Facebook was
difficult and not completely satisfactory, but the
assignments were fun for the students. The surveys were
about things that were specific to the local campus and
would not be of interest to others.)
