Mnemonic techniques
(from P.A.Wozniak, Economics of Learning)
Mnemonic techniques go one step
further than the graphic approach in this sense that they use
artificially redundant graphic images to represent unique or
nonsensical information. One of the two fundamental mnemonic
techniques are mind maps and peg lists. A mind map is a graph
that in a vivid form represents the structure of semantic
connections between particular components of the learned
knowledge. A graphic model of market economy might be an example
of a mind map; however, mind maps are applicable also to all
pieces of semantically coherent knowledge, independent of their
usual form of representation in standard textbooks. Thus, the
computation of the combination of products that maximizes the
customer’s total utility (see previous section) might also
be presented in a graphic form. A flow chart is the most
impelling proposition, though any other form of a not necessarily
directed graph might do. An interesting variety of a mind map is
a graph that is mapped on the image of a familiar object, e.g.
one’s own apartment. Retrieving particular pieces of such a
graph from memory is particularly easy, though the solution is
not always universal because of the fact that each student would
rather use mapping familiar for him or herself. The most often
applied universal mapping is the one that pegs particular nodes
of the mind map to the parts of the human body. The main
shortcoming of the presented approach is strong interference
between multiple mind maps pegged to the same object.
Another popular mnemonic technique is peg lists. A peg list is a
sequence of well visualized objects associated with cardinal
numbers. For sophisticated applications, peg lists usually
consist of 101 objects pegged to numbers from 0 to 100. The main
application of peg lists is in remembering numbers and ordered
enumerations. A 101-element peg list can be used to represent all
numbers as sequential visual scenes composed of peg list
equivalents of two-figure components of the remembered number.
For example, assume that a phone number 867045 is supposed to be
memorized by means of a peg list. Assume that the following
images are associated with the two-figure components of the
number: 86 - car (first car was built by Carl Benz in 1886), 70 -
phone (Graham Bell invented the phone in 1870), and 45 - bomb
(the date of Hiroshima bombing). If we imagine a scene in which
we drive a car, pick-up a mobile phone and spark off a great
fireball by activating the ringer, then we have effectively
mapped an otherwise nonsensic phone number onto an easily
retrievable graphic scene (the mapping being effected through the
peg list).
To illustrate the phenomenon of increasing returns to scale, and the incredible competitive advantage the Ford Motor Company has gained in the early 1900s over its competitors though specialization of labor based on semi-automated assembly lines, the student might wish to note that in 1914 the FMC produced 270,000 cars with 13,000 employees; while the other 299 American auto companies at the same time, with 66,000 employees produced just 290,000 cars. The example posses a serious dilemma to a knowledge system developer. Each of the number quoted makes up useless garbage knowledge. However, taken together, the figure combine into a vivid and compelling illustration of increasing returns to scale and their importance in running any kind of business. Demanding from the student the understanding of increasing returns to scale deprives the example from its strong emotional overtones, as the student might identify him or herself with Henry Ford’s business cunning. Depriving the example from numbers takes a great deal of its vividness. The two proposed solutions are: (1) limit the question to an estimated figure that shows the FMC lead in the market, and (2) use Cloze deletion to dismember the above sentence, and use mnemonics to memorize the involved numbers. The first approach might look as follows:
Q: What was the share of the American automobile market commanded by the Ford Motor Company in 1914?
A: Close to 50%
or using Cloze deletion and mnemonic techniques:
Q: In 1914 the Ford Motor Company produced 270,000 cars with 13,000 employees; the other ... American auto companies, with 66,000 employees produced just 290,000 cars.
A: 299 (Ford turns on a light switch to see how many competitors he has got, and ... only two cats spring up turning their tails)
The seemingly flippant comments in the parentheses above are part and parcel of mnemonic representation. In the example above, an eleven-member peg list has been used with the number two represented by a light switch (the switch has two states: on and off), and nine represented by a cat ("cat has nine lives").
As the analysis of intractable items in numerous knowledge systems show that numbers take the lead in making items indigestible to human memory, the use of numbers in knowledge systems of all sort should be limited to the absolute minimum. As the discussed knowledge system on microeconomics was notably sparse in numbers (mathematical formulas do not count here), the above example was a notable exception, and, perhaps for that reason, did not cause any serious recall problems. However, had there been more such numerically saturated cases, the issue could have started being a problem.