Milo and others,
I can vouch for this simple approach. In my experience it is only students
in education who have difficulty with logs. Ratio paper helps if you use
more than three cycles as you can easily show that the chart plots equal
multiply (as opposed to the add-subtract equal interval charts they use
almost to exclusion). When asked about the ratio chart I point out that it
simply multiplies plotted data and have them plot a X2 series, then a X3
series. By then most will stop "fighting the log "ratio" chart and you can
get on with the statistic. If worse comes to worse, plot an equal interval
beside a ratio chart and they will see that the ratio chart plots a straight
line while the equal interval (add-subtract) chart plots a curve.
Looking Forward,
Dennis
[In the beginning there was the Sponse...
Dennis L. Edinger
7901 W. 52nd Ave., Apt. 118
Arvada, CO 80002-4520
Ph/Fax 303-421-6329
-----Original Message-----
From: Concerned with the initial learning and teaching of statistics
[mailto:[log in to unmask]]On Behalf Of Milo Schield
Sent: Monday, October 22, 2001 4:09 PM
To: [log in to unmask]
Subject: Re: teaching introductory progression
Vincent,
Instead of using "LOGS" which many do not understand,
just show the original numbers plotted on a RATIO scale
-- which most students can readily understand.
[Yes, the scale will be logarithmic, but that is incidental.]
Sales people certainly understand percentage growth.
Having a scale where a constant percentage increase
generates a straight line should be fairly easy for these
students to grasp.
The distinction between base 10 and base e should
also be irrelevant for your students' understanding.
In your context, it sounds like LOGS are just a means
to accomplish the desired end. It doesn't sound like
students need to understand the definitions and/or
the properties of LOGS to understand diminishing returns.
Milo
==============
At 05:27 PM 10/17/2001 +0200, you wrote:
>Hello
>
>Can someone help please ? :
>
>i am trying to introduce some basic stats techniques to a group of sales
>
>people: they are bright but have no math at all !!!
>
>As part an introduction I want them to understand the law of
>diminishing returns
>
>and thus arithmetic progression and am using the old question
>"If an activity that has 20 operations "how many possible ways are there
>of completing the task ?"
>
>
>I get them to draw up a table in Excel and they get the visual very
>quickly
>but when i try to grapth the progression ....
>
>
>I can get the grapth the way i want but only if i use a log fuction
>(Naperian log) and then make scattter graph but these guys
>don't get logarithms
>
>
>Any ideas
>
>rgds
>Vincent
>--
>Vincent Short
>Chargé de Relations Entreprises / Corporate Relations
>Groupe ISAIP-ESAIP
>BP 22
>18 rue du 8 Mai 1945
>49180 St Barthélemy d'Anjou
>
>France
>
>TEL + 2 41 96 65 24
>Fax + 2 41 96 65 11
Milo Schield, Professor. Department of Business Administration
Project Coordinator, Keck Statistical Literacy Project
Statistical Literacy leader, Quantitative Literacy Team, Project
Kaleidoscope
Augsburg College Minneapolis, MN 55454 612:330-1153
Home Page: www.augsburg.edu/ppages/~schield
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