Psychology Thurstone

Thurstone holds an instrumental role in the developments of psychometrics and psychophysics. In this article, we will learn about Thurstone’s life and significant works. However, we will focus on the Thurstone scale and its uses in psychology. 

Who is Thurstone? 

Louis Leon Thurstone, born on 29th May 1887, was an American psychologist who was the pathfinder in psychometrics. Psychometrics is the science that measures mental functions and attitudes. He was the most renowned psychometrician of his time and is considered the 88th most cited psychologist of this century. 

An influential psychology theorist, he is well known for his contribution to factor analysis. Similarly, he garnered a lot of attention with his discovery in the measurements of intelligence. 

Before explaining his significant works, let us know about his background and life.

Life and background

Born in Chicago to Swedish immigrant parents Conrad and Sophia Thunstrom, Louis’ life was transient. For the first 14 years of his life, he moved with his family around different cities in the United States. Hence, he had to attend various schools, and the transitions helped him attain multicultural education. 

Later, the Thunstrom family changed their surname to Thurstone to avoid confusion. Louis had to move to Illinois from Chicago and Mississippi for his father’s changing careers. From there, they moved to Sweden and stayed there for six years until finally settling in New York State when he was fourteen. 

Education

Thurstone was initially interested in mathematics and engineering. Louis started studying civil engineering at Cornell University, New York, in 1908. However, later he changed to electrical engineering and received his Master’s degree in 1912. 

While at Cornell University, Thurstone developed a patent motion picture projector. Thomas Edison liked his work and demonstrated the design at his laboratory. Following that, Thomas Edison offered Thurstone an internship in his laboratory. 

Louis Thurstone left Edison’s laboratory in East Orange, New Jersey, to pursue a teaching career at the University of Minnesota. In the fall of 1912, he started teaching the course of descriptive geometry and drafting in the College of Engineering. 

Interest in Psychology

Thurstone became interested in the psychology of learning and human factor through his teaching experience. He also believed that good engineering involves the study of human psychology. He delved deeper into how people would learn to use an engineering tool, hoping that psychology would provide answers. 

In 1914, he enrolled at the University of Chicago as a psychology graduate. He completed his PhD in 1917. After that, he was appointed the chairman of the psychology department at the Carnegie Institute of Technology. In 1924, he returned to the University of Chicago to become the associate professor of psychology and spent 28 years teaching there. 

After he retired from the University of Chicago, he established L.L. Thurstone Psychometric Laboratory. In the last three years of his life in North Carolina, he founded the psychometric society and published many important books on this field. 

He breathed his last on 30th September 1955 from heart failure leaving behind his psychologist wife, Thelma, and three children. 

What is the Thurstone scale?

The Thurstone scale is the first formal technique to measure a respondent’s social attitude towards a topic. This unidimensional scaling method employs an agree-disagree format of questions. It is typically used in the fields of Psychology and Sociology. 

The Thurstone scale is a quantitative method where a respondent’s opinion is scored. The scaling format consists of statements on a particular topic with a designated numerical value. The score indicates if the statement is favourable or unfavourable to the respondent. Finally, the average score is calculated to measure their attitude towards an opinion. 

For instance, if a respondent agrees to 4 out of 10 statements, they are 40% towards the opinion. As the rest 60% of the statement is disagreed by the respondent, they are unfavourable to the particular examination subject. Similarly, the higher the score, the more favourable the opinion. 

The Thurstone scale is very effective in statistical comparisons, and its usage goes back to the early 20th century. Before entering the fields of psychology and sociology, the scale was popular in religion.

Methods of Thurstone scale

The Thurstone scale is divided into three methods of measuring: 

Method of Equal-Appearing Intervals

In the Thurstone scaling design, the most sought-after method is equal-appearing intervals. This method chooses items that are equally spaced apart in the test.

Method of Successive Intervals

Though this method was designed to overcome the difficulties of the equal-appearing method, it is more complex to implement.

• Method of Paired Comparison

The last method is very consuming and requires twice the judgement as to the method of equal-appearing.

• Other significant works of Thurstone

Thurstone’s significant works include

• Factor Analysis 

Thurstone first coined the term factor analysis, which aims at calculating significant common factors in a correlation matrix. Analysing the common factors can rank them in the order of importance to the correlation. For instance, this method can determine the contributors to intelligence.

Theory of Intelligence

Louis Thurstone established that the differences in intellect depend on seven abilities. They are space, word fluency, verbal comprehension, number facility, rote memory, perceptual speed, and arithmetic reasoning. 

Psychological Scaling 

Psychometric scaling measures a psychological concept by analysing responses to a set of stimuli. 

Books, publications, and awards 

Louis Thurstone was excellent in academics and started publishing at sixteen. His first publication was in Scientific America. His major publications are following:

• The Nature of Intelligence (1924)
• The Fundamentals of Statistics (1925)
• The Measurement of Attitude (1929)
• The Vectors of Mind (1935)
• Multiple Factor Analysis (1947)

He also received numerous awards and honours. Some of which are the Centennial Award from Northwestern University (1951) Honorary Doctorate from the University of Goteborg. He was also the President of the American Psychological Association. 

Conclusion

Measuring attitudes and comparing opinions of the respondents is a difficult task. Students have faced difficulties in the complex process of studying the design and analysing. However, the quantitative method of Thurstone’s attitude measurement has reduced the difficulty.