Lee Joseph Cronbach: biography of this psychologist

This psychologist was the creator of Cronbach's alpha index, widely used in psychometrics.

It is difficult, or even impossible, to carry out research in psychology without the influence of Lee Cronbach.

He is an essential author for understanding psychology as it is today, and undoubtedly one of the most influential scholars of the last century.

His numerous contributions to the knowledge of science have a transversal character, since he devoted himself to epistemological reflection and to the definition of a method with which to enhance the rigor of the scientific findings that could be derived from this discipline.

Biography of Lee Joseph Cronbach

In the following lines we will delve into the life of the author through a brief biography of Lee Joseph Cronbach. a brief biography of Lee Joseph CronbachWe will now focus on some of his most important contributions.

Academic career

Lee Joseph Cronbach was a psychologist of American origin who made numerous contributions to the field of psychometrics and education, among which the Cronbach's alpha index (widely used today to determine the reliability of a quantitative assessment tool) stands out.

Lee Cronbach was born in the city of Fresno in 1916, where he obtained his university degree (Bachelor of Arts, 1934), and later obtained his Master's degree in Berkeley and his Ph.D. in Chicago (Educational Psychology, 1937). Throughout his career, he showed interest in the methodological rigor of the studies published within the framework of psychology.He proposed important tools to strengthen it.

As a teacher, he taught at many universities in his country, especially at Chicago, Illinois and Stanford (where he remained for a large part of his life as an academic). In recognition of his extensive contribution, Lee Cronbach was appointed president of the American Psychological Association (APA) in 1957 and of one of its divisions (Assessment and Measurement), as well as of the American Educational Research Association itself in 1964.

In addition to his contribution to psychological assessment, he developed major work in the field of instruction. During the 1970s he had the opportunity to be the director of the Stanford Assessment Consortiuma research and training organization that was attached to the Psychology departments and designed extensive projects to improve coordination among schools in the districts that make up the State of California.

Cronbach's research was also relevant in clinical and community settings. He developed programs for health and juvenile delinquency, emphasizing an extraordinary rigor in his work and making visible the importance of social and political reality in the planning and development of these programs.emphasizing an extraordinary rigor in his work and making visible the importance of social and political realities in their planning and development. With these contributions, he substantially improved the way in which research was developed in the social, health and educational fields.

Lee Cronbach died in 2001 of congestive Heart disease, leaving to posterity an enduring intellectual legacy for the future. an everlasting intellectual legacy for Psychometrics, Educational Psychology and Epistemology.. Not in vain, he is one of the authors with the largest number of references in scientific articles worldwide.

Theoretical and epistemological principles

The variety of studies in which the author's work is used exemplifies very well one of the postulates on which it is based, which is none other than the existence of two independent but firmly related psychologies: one experimental (which requires manipulation in the laboratory to observe causes/consequences with absolute control of the situation) and the other correlational (through which one could observe the way in which two variables interact with each other in less restrictive environments).

Lee Cronbach's vision of Psychology aspired to the formulation of essential laws that could become widely applicable and generalizable, in a similar way. and generalization, in a manner similar to that of physics or chemistry. He believed that it was possible to disentangle the associations that occur in human phenomena in order to establish a posteriori causal relationships that, even based on the laws of probability, would bring his object of study closer to the positivist rigor of other disciplines.

Thus, he understood human behavior and thought as realities imbued in nature, and therefore subject to the same explanatory principles as the natural sciences. The latter sought to establish certain regularities among the phenomena under study, with a special sensitivity to the probability of error inherent in their complexity, but elaborating universal principles on which to base a useful and reproducible body of knowledge.

Lee Cronbach was able to recognize that the purpose of psychology should not be limited to the experimental reproduction of laboratory conditions to test assumptions of a nomothetic nature (applicable to all subjects as particles extracted from a group), but should contemplate the phenomena that unfold in everyday environments. In this sense, he aspired to the unification of the two psychologies that he himself distinguished, in an attempt at syncretism.in an attempt at syncretism that would prove to be paradigmatic.

Lee Cronbach's reflections on this question led him to affirm that the reduction of psychic phenomena that occurs in experimental situations could not give a precise answer to the problems of the human being, whose life is debated in the permanent flow of interactions with a multiplicity of variables, among which the basic socio-cultural coordinates and the substratum of the scenario in which his day-to-day life unfolds would be emphasized.

In conclusion, I would point out that the observation of the phenomena (with a mind devoid of prejudices and open to fascination) is the key to establish a knowledge of sufficient entity to equate it with that of Physics or Chemistry.. Regarding the latter, I would remind that they are not free of uncertainty either, since the macro and microphysical world assumes a virtually infinite number of variables for their formulations).

Contributions as a methodologist

Lee Cronbach's vision of psychology was a historical milestone, showing the desire for positivist equalization with other sciences from a perspective that embraced reason and circumvented all naivety. However, the contribution for which he continues to be so well remembered today was his famous Cronbach's alpha, a measure inserted within the G-Theory (or Generalization Theory). Theory (or Generalizability Theory) with which the Classical Theory of Tests was expanded.

The Classical Test Theory contemplates that any score (empirical value) that a subject obtains in tests designed to measure a psychological construct is made up of his real score plus the random error (this being the difference observed when subtracting the empirical score and the real score). This error can occur as a result of methodological deficiencies, or even of circumstances such as the place where the measurement is carried out or the personal situation of the test taker.

The G Theory would be complementary to the Classical Test Theory.. It would seek to quantify the reliability of a test through the determination of all sources of error, guaranteeing a more accurate decision-making process. This process occupied a considerable part of the author's academic life, for which he suggested methods coming directly from statistics.

In this context, Cronbach's alpha would rise as one of the statistics designed to assess one of the statistics designed to assess the internal consistency or reliability of a measurement tool (or of its component factors). (or of its component factors). Although the concept was introduced by Cyril J. Hoyt (a professor in the Department of Educational Psychology at the University of Minnesota) and Louis Guttman (a mathematician and sociologist at the Hebrew University of Jerusalem) some years earlier; it was Cronbach who was finally able to popularize it, reformulate it and extend it to the scientific community to a greater extent.

Whenever a researcher intends to measure an attribute, has to take into account the fact that it is never directly quantifiable, but that its assessment must be carried out in a way that is not directly quantifiable.The assessment must be carried out through a process of abstraction that is in line with the theoretical model from which it is derived. This is usually done by administering a questionnaire, the items of which are subsumed as second-order factors (depression or anxiety, for example).

Cronbach's alpha is used to evaluate the way in which the measure is accurate and explores with minimum margin of error what it really claims to measure. It is the weighted average of the variances or correlations among the items that make up the factorThe score obtained from its use ranges from 0 to 1 (being 0.70 the cut-off point from which the test can be considered reliable and used for assessment purposes in any field of psychology).

An assessment at the service of society

Psychological assessment, for Cronbach, was linked in an indivisible way to social policies, and should be subject to the needs of the people in their aspiration to achieve a state of justice and plurality.. He understood that although political influences were inevitable, it was necessary to have a process of adaptation between these and social programs based on sensitivity to needs through a flexible approach to the object of study.

Because of this vision, he postulated an evaluative planning that could accommodate the enormous diversity to which each potential research was subject, in which two stages were included: the convergent and the divergent. In the first, the possible variables to be explored were extracted, while in the second, a hierarchy of priorities for the study was established.

Finally, the same author considered that the interpretation of results was a second stage in the evaluation of the results, in which part of the information could be lost. information could be lost due to the subjectivity of the evaluator.. That is why he considered essential a structured training aimed at selecting appropriate questions and directing the process to action, that is, towards a decision making process that prioritizes the improvement of the lives of the people or institutions evaluated.