Summary for Week 2 (September 21-23)

We started Chapter 2 by discussing an interesting (and historical) graph by C. Minard who described the movement of Napoleon's army in the 1812-13 Russian campaign. (We also heard a piece of classical music.)

We continued by looking at the shape of a distribution and learned about stem-and-leaf diagrams, dot plots and histograms. In all cases we used MegaStat to draw these graphs. We discussed a method for determining the best value of K and L, and drew a histogram with correct class lengths and number of classes.

We discovered that many data sets are symmetrical, but they could also be positively- and negatively-skewed. (McMaster salaries we looked at were positively-skewed.)

Next, we reviewed the mean, median and mode as measures of central tendency. The variability measures of range (not too useful), variance and standard deviation were introduced. (Recall the example I gave with two buckets of water.) The sample standard deviation has a slightly different formula for which I gave an intuitive explanation.

We will continue with the Empirical Rule for "normal populations" which we did not finish yet.

I plan to complete Chapter 2 next week.

Summary for Week 1 (Septembr 14-16)

We started by taking a quick look at the course outline.

In Chapter 1, we discussed the use of statistics in different disciplines, defined populations and samples and looked at the sampling problem associated with the "Dewey defeats Truman" incident in 1948.


Next, we learned how to generate random numbers (marbles in a bucket, random number table, and finally by MegaStat).  We classified data as quantitative vs. qualitative, and cross-sectional vs. time-series. For the time series case we looked at the coffee temperature case (Stella Liebeck vs. McDonald's).

The two concepts of being in statistical control, and being capable were also introduced. We wrapped up our discussion with a look at a blood pressure data taken over time, thus completing Chapter 1.

Help on Installing MegaStat

As I indicated on page 4 of the course outline, please refer to,
(i) Excel's help on "add-in", and
(ii) MegaStat's <GettingStarted-MegaStat07.pdf> file for installation instructions. This .pdf file is on the CD that comes with the book.

Section C02 (2010-09-16)

I was planning/hoping to spend a minute or two on plotting a MegaStat graph of 24 coffee temperature values in the Excel file on the course web site:

http://www.business.mcmaster.ca/courses/q600/ChapterComments/documents/CoffeeTemp.xls

As you remember, the system turned itself off at the end of the class and I couldn't show you the Excel file.

Here are the steps to follow to plot the graph (assuming that you have installed MegaStat):

Double-click on the file and start Excel | Add-Ins > MegaStat > Descriptive Statistics > Input Range (A2 to A25) > Choose Runs Plot > OK

Does the Runs Plot indicate that the process (coffee temps) is in statistical control, and capable?

First blog from Dr. Parlar

Dear Bus Q600 students.

This is the first time I am using a blog in any of my courses. I hope you will find it useful.

Let me know how we can make good use of this new tool to improve the learning process in our course.

Please sign in (on the right) using your Google, Twitter or Yahoo accounts.