Operationalization

The operationalization (or Messbarmachung ) is the generic term of measurement, scaling and index construction. It sets out with a theoretical construct which indicators should be (eg justice ) measured.

For example, the processing speed of the human brain may, inter alia, be operationalized by means of the reaction rate.

In addition to the measurement, as here, for example, the reaction rate must be for the operationalization but also the survey methodology, the survey instrument and in particular the parts with which the empirical information is to be obtained, are described. Finally, it is to explain the process as the information for the actual analysis is prepared. For the operationalization of a theoretical construct also includes the question of which level of measurement should have the indicators used.

The operationalization has in all the sciences of great importance, since it is the basis for the experiments can be repeated, because only in that an experiment is repeated, and would the same results be achieved, a hypothesis can be tested reliably.

Example

Is to be measured, the theoretical construct " processing speed of the human brain ." Operationalization could be an experiment in which a subject is placed in front of a device that consists of a single lamp and a pressure switch. Lamp and pressure switch are connected to a computer stopwatch that is started when the light comes on and stops when the subject presses the switch. This is the description of the survey instrument.

The switch is so designed that it stops the timer at the moment in which the finger of the test subject touched the switch. The patient must therefore overcome any resistance to trigger the switch ( description of the parts of the instrument, which are used for obtaining the information).

The subject receives the task of pressing the switch once the light comes on. As far as the description of the survey method.

In computer other socio -demographic data of the subjects in addition to the data of the stopwatch still be collected and stored ( preparation of information for the actual analysis ).

Quality criteria

The results of an empirical study can significantly depend on the choice of operationalization. Therefore, indicators and operationalization in science must fulfill three main quality criteria:

• Objectivity or intersubjective comprehensibility
• Reliability ( reliability)
• Validity ( validity )

Example: It will be found between the distance of the ears and the intelligence of a strong relationship if you operationalized intelligence by the head circumference. A critic could object to this conclusion that the head circumference is not a valid measure of intelligence ( it is not measured by what should be measured). Has the investigator also a tape measure made ​​of stretchy rubber is used, the reliability would be to complain about ( two measurements give different results ). Moreover, if has not been recorded, at which point the tape measure should be placed at the head of the person and another researcher the measurement itself therefore can not understand, so no objectivity ( intersubjective comprehensibility ) is given.

Validity sets when considering reliability ahead: If the measurement does not even reliable, so it can certainly not measure what should be measured. A validity coefficient can not be greater than the square root of the reliability coefficient.