Page 19 - Rapid Learning in Robotics

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It enlarges the field of problems and relevant disciplines, and in-
cludes also material, engineering, control, and communication sci-
ences.

The time for gathering training data becomes a major issue. This
includes also the time for preparing the learning set-up. In princi-
ple, the learning solution competes with the conventional solution
developed by a human analyzing the system.

The faced complexity draws attention also towards the efficient struc-
turing of re-usable building blocks in general, and in particular for
learning.

And finally, it makes also technically inclined people appreciate that
the complexity of biological organisms requires a rather long time of
adolescence for good reasons;

Many learning algorithms exhibit stochastic, iterative adaptation and
require a large number of training steps until the learned mapping is reli-
able. This property can also be found in the biological brain.
There is evidence, that learned associations are gradually enhanced by
repetition, and the performance is improved by practice - even when they
are learned insightfully. The stimulus-sampling theory explains the slow
learning by the complexity and variations of environment (context) stimuli.
Since the environment is always changing to a certain extent, many trials
are required before a response is associated with a relatively complete set
of context stimuli.
But there exits also other, rapid forms of associative learning, e.g. “one-
shot learning”. This can occur by insight, or triggered by a particularly
strong impression, by an exceptional event or circumstances. Another
form is “imprinting”, which is characterized by a sensitive period, within
which learning takes place. The timing can be even genetically programmed.
A remarkable example was discovered by Konrad Lorenz, when he stud-
ied the behavior of chicks and mallard ducklings. He found, that they im-
print the image and sound of their mother most effectively only from 13
to 16 hours after hatching. During this period a duckling possibly accepts
another moving object as mother (e.g. man), but not before or afterwards.
Analyzing the circumstances when rapid learning can be successful, at
least two important prerequisites can be identified: