T.O.T.E.

The T.O.T.E. or TOTE, standing for "Test - Operate - Test - Exit", is an iterative problem solving strategy based on feedback loops. It was described by George A. Miller, Eugene Galanter, and Karl Pibram in their 1960 book, Plans and the Structure of Behavior.

The TOTE Unit in Human Cognition

The self-control mechanisms in human tasking are explained in terms of both operations and monitoring processes. Each recurring operation would be associated to a monitoring process, to test if the intended control was met or not.

Its premise is that a common algorithm for solving non-deterministic problems in a complex system, is to test where the system is currently, then perform some operation that makes a change, then retest again, and to repeat this until the answer is satisfactory, at which point the process is complete and ends (or exits).

The generic TOTE structure is:

  1. Test to obtain some representation of the problem state
  2. Operate - intervene in some way
  3. Test again to see if the problem state is the same - if it is loop back to operate if it isn't
  4. Exit - Problem Solved

TOTEs are often nested within other TOTEs, since as a means to meet a goal, they are applicable to sub-goals too.

TOTE units commonly used in many disciplines where iterative methods are applicable, such as engineering, artificial intelligence, and cybernetics. In psychology, it is explicitly used as a key strategy within neuro-linguistic programming.

Central to the concept of the TOTE unit are the following principles:

  1. Working memory is limited to 7±2 chunks of information.
  2. Planning, consisting of TOTE units, is essential in cognitive process.
  3. Control of behavior exposes a set of chunks and TOTE units

Examples

The following is an example of a simple TOTE: When driving a car and looking for the appropriate turn off.

  • Test - is this the turnoff? - No
  • Operate - keep driving
  • Test - is this the turnoff? - No
  • Operate - keep driving
  • Test - is this the turnoff? - Yes
  • Exit

(this only finds the correct turnoff, and would be embedded in a larger TOTE)

A TOTE can also be nested within other TOTEs, for example: Cooking a meal:

  1. The top level TOTE for "testing if meal is cooked" is:
    Check meal -- leave a while -- recheck meal - take out of oven.
  2. As part of the "leave a while" part, there is a nested TOTE:
    Check 5 minutes is up -- wait a while -- recheck 5 minutes is up -- exit (ie "leave a while" subgoal is achieved)

See also

  • Eugene Galanter
  • George A. Miller
  • The Magical Number Seven, Plus or Minus Two
  • Automata theory

References

  • Miller, GA, Galanter, E., & Pribram, KA (1960). Plans and the structure of behavior. New York: Holt, Rhinehart, & Winston.

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