Statistics / Sadistics

1
Statistics / Sadistics

• Juggling
• Basic
• Statistical
• Notions
• Important For
• Teachers
• While
• Maintaining
• Sanity

2
Remember . . .

• There are three kinds of people in the world.
• Those who are good at math, and
• Those who arent.

3
Raw Scores without organization or context,
scores by themselves are meaningless

• George Carlins famous line Heres a partial
  football score just in, Green Bay 6.
• Ohio State 35 Michigan 32
• Annika Sorenstam 35 Lorena Ochoa 32
• John and Charley are taking a trip together.
  Charley has lived for 7 years John has lived for
  27. Who is the older of the two?
• Charley
• John
• Charley is a dog. In human years he is 46 e.g.,
  (7-1) x 5 16 46. John is a man. In human
  years he is 27.

4
Edward L. Thorndike (1874-1949). . . his pioneer
investigations in the fields of human and animal
learning are among the most influential in the
history of Psychology.
Whatever exists, exists in some quantity. If it
exists in quantity, it can be measured. E. L.
Thorndike (quote paraphrased)
5
The McNamara Fallacy . . . attributed to
economist Charles Handy

• The first step is to measure whatever can be
  easily measured.
• This is okay as far as it goes.
• The second step is to disregard that which cant
  be easily measured, or to give it an arbitrary
  value.
• This is artificial and misleading.
• The third step is to presume that what cant be
  measured easily isnt important.
• This is blindness.
• The fourth step is to say that what cant be
  easily measured doesnt exist.
• This is suicide.
• Bottom Line of the Robert McNamara fallacy
• What does not get counted does not count.

6
English Lesson When Speaking of Data

• As a teacher, you will see lots of data.
• The dictionary defines data as facts or
  figures. Notice the word data is plural and
  when speaking of data you need to use plural verb
  forms. It is an unfortunate giveaway that you
  might NOT know what you are talking about if you
  use the phrase this data is instead of these
  data are in professional conversation.
• Datum is the singular form for data. No one
  ever uses this term.

7
Scales of Measurement Organizing and Comparing
Data the use of Zero

• The first is Nominal. It is data that is
  categorized and can't be arranged in an order
  from low to high e.g. answer a question yes or
  no, colors of cars in a parking lot, race and
  gender.
• The second is Ordinal. It is data that is
  categorized and can be arranged in an order from
  low to high, but differences between the scores
  can not be determined, or are meaningless e.g.
  grades A, B, C, D, E or grade levels 9th, 10th,
  11th, 12th, or survey type questions such as do
  not like, somewhat like, like, love or another
  is movie ratings.
• The third is Interval. It is the ordinal scale,
  but with the additional property that the
  difference between the data (i.e. the interval
  size) is equal, but the scale does not have a
  natural zero starting point e.g. the years
  (2009, 2000, 1610, etc), the temperature scale
  (50, 68, 90, etc degrees F).
• The fourth is Ratio. It is the interval scale,
  but with the additional property that it does
  have a natural zero starting point. Money and
  weight are examples 0 money means you have none,
  and 4.00 is 2 X 2. Likewise with weight no
  weight means there is none and 4 pounds is 2 x 2
  pounds.
• Note Despite evidence that grading as punishment
  (such as the use of zero for missing work) does
  not work (Guskey, 2000) and the mathematical flaw
  in the use of the zero on a 100-point scale
  (Reeves, 2004), some teachers persist. Will you?
• Guskey, T. R. (2000). Grading policies that work
  against standards and how to fix them. NASSP
  Bulletin, 84(620), 2029.
• Reeves, D. B. (2004). The case against zero. Phi
  Delta Kappan, 86(4), 324325.