Hypothetical Concept – Concept assumed to be present. It existence, however, has not yet been demonstrated experimentally.
Hypothetical Construct – A concept or idea that is positioned between the observation and the results of a study. The construct is of a theoretical nature. It provides an explanation for an aspect that is essentially abstract. For example: intelligence, attitude, learning, etc. See also: Intervening Variable/ Attitude/Learning
Model – 1. A mathematically formalized theory. A theory expressed in terms of symbols.
2. A segment of reality that is copied as precisely as possible on a small scale (for example, a factory modeled in cardboard). See also: Laboratory
Nomological Network – A theoretical body with all its main and partial theories, hypotheses and related theories.
Null Hypothesis – A kind of hypothesis exclusively intended for statistical purposes. The null hypothesis proposes in every instance that no mutual coherence exists between two phenomena that are being studied. The investigator always hope that this hypothesis will be refuted, since then mutual coherence may be discovered.
Occam’s Razor – Syn: Parsimony Principle See: Parsimony Principle
Parsimony Principle – Syn: Occam’s Razor A principle having to do with the formulation of theories: the shorter and simpler the theory, the better. The more (new) concepts the theory includes, the greater its obscurity. The search is for the theories that explain a great deal while using as few words (or symbols) as possible.
Pledge to Explicate – The duty that rests with the proponent of a theory to support the theory with data concerning the manner in which it should (best) be put to the test. See also: Empirical reference/ Testing
Probabilistic Hypothesis – One of the simplest forms of hypothesis used in experimental research. Fundamental form: there are more A’s than B’s. For example: more French cheese is consumed in the United States than in the United Kingdom.
Refutation of a Hypothesis – Syn: Falsification of a Hypothesis See: Falsification of a Hypothesis
Theory – A system a logical, coherent and non-conflicting assertions, conceptions and viewpoints concerning some aspect of reality, formulated in such a manner as to afford the possibility of generating testable hypotheses.
Universal Deterministic Hypothesis – Hypothesis having as fundamental form: All A’s are B. For example: all adult Americans own at least one radio. If one American is found who does not own a radio, the hypothesis has already been refuted.
Working Hypothesis – Hypothesis of a very provisional nature. It is actually more a frame of thought or a point of departure than a hypothesis. The same holds true for working theory.
Coefficient of Equivalence – The correlation-coefficient of two parallel parts of test. The measure of coherence between two parts of a test, expressed as a number. See also: Parallel form Method/Correlation-coefficient
Coefficient of Stability – The correlation-coefficient between test results obtained from having the same group of persons perform the same test twice. It indicates the degree of constancy for a test, expressed as number. See also: test-retest Method/ Correlation-coefficient
Concurrent Validity – A form of validation. It is ascertained how two criteria that are different correspond to one another. For example: A housewife completes a questionnaire concerning the estimated price of a number of products. This list is compared with the (average) factual prices.
Construct Validity – A form of validation. In a testing situation it is a question concerning the concept being measured. Is the concept, in fact, being measured by means of the relevant test questions? What is being measured in fact? For example: construct validity pertaining to the concept of honesty; does the test for honesty (with its test questions) really measure honesty? Or does it measure creativity or some other factor? The determination of construct validity is often troublesome and time-consuming.
Content Validity – Content validity involves the question. Are the items (questions) included in the test adequately large and sufficiently differentiated to create a representative sample? See also: Sample
Cross Validity – The comparison of a test, test question or part of a test with a criterion (norm) that falls outside this test. The object is to establish a firm basis for the test. For example: a test that predicts satisfactory performance from certain students in high school is compared with their final examination grades at the time of leaving school. Persons from whom a satisfactory performance had been predicted, should have high grades; otherwise, the test would have failed.
External Validity – The validity of an instrument, questionnaire or test that is not inherent. For example, the external validity of an electoral opinion poll lies in the result of the election itself. See also: Validity
Face Validity – A questionnaire or test may at times seem valid. After it is investigated, it proves to be invalid. For example, is a question pertaining to purchasing intention valid? In other words, when person indicate an intention to purchase a certain product, will they, in fact, do so? Research has shown that people do not, in every instance, say what they they do (or do what they say)
Instrumental Utility – The utility, the effectiveness, of an instrument or test. An adequate test measures what it is intended to measure. See also: Pretension/Instrument
Interjudge Reliability – Syn: Interrater reliability/Intersubjectivity The concurrence among a number of judges in a test, a study or a performance. Each judge provides his own subjective judgment. In the instance of a high degree of concurrence in all these judgments, interjudge reliability is said to exist – which does not, however, guarantee objectivity See also: Objectivity/Subjectivity