Psychometric Testing

Critical Perspectives

Barry Cripps, Barry Cripps

• Publisher: Wiley-Blackwell
• Year: 2017
• ISBN:
  9781119183006
• Edition: 1
• Topic: Psychology
• Subtopic: Industrial & Organizational Psychology
• Index: Psychology

Psychometric Testing offers an in-depth examination of the strengths and limitations psychometric testing, with coverage of diverse methods of test development and application.

• A state-of-the-art exploration of the contemporary field of psychometric testing, bringing together the latest theory and evidence-based practice from 21 global experts
• Explores a variety of topics related to the field, including test construction, use and applications in human resources and training, assessment and verification of training courses, and consulting
• Includes applications for clinical psychology, performance psychology, and sport and exercise psychology across a range of professions (research, teaching, coaching, consulting, and advising)
• Acknowledges the dynamic nature of the field and identifies future directions in need of more research, including Internet and smart phone testing

Part I
History, Theory and Utility

1
The History of Psychometrics

Craig Knight

He had the personality of kipper; on an off day.

Joan Collins

Think about the people you know for a moment. Have you ever wondered how Chris manages to maintain a sense of equilibrium under even the most testing circumstances, or why Sam is more irritating than a starched collar? Why are some people like balm to a wound, while others look to start a fight in an empty room? And wouldn’t it be useful if you could predict people’s behaviour patterns before an event rather than ruefully mopping up afterwards?

Humans have been speculating on and assessing their own variables since Cain weighed up Abel, often with the success of somebody nailing fog to a wall. If it’s hard to judge those we claim to know best, just how can you assess the personality of a good accountant, manager or leader? Of course Tibetan Buddhists re-select the same leader on an eternal basis. The rest of us have to make a more or less educated assessment of the candidates available.

It is this assessment that is central to psychometrics. If we accept the definition of psychometrics as ‘the science of measuring mental capacities and processes’ (en.oxforddictionaries.com, 2016) then the quality of that science becomes the predictor of its success.

As we will see, psychometrics is a flawed discipline. Its advocates can be vociferous and wrong. Vaunted predictive capabilities go unchecked and snake oil oozes from the cracks of many psychometric creations. No matter how persuasive the personality advocate and how beguiling the evidence, we do well to remember that nobody ever equates to a yellow circle, a traffic light or a bear. Only decent instruments – probably in the hands of trained assessors – can link skills, propensities and personalities to jobs, proclivities and outcomes.

Well-researched psychometrics can test for the qualities required in a boardroom or back office or bakery. So while these tools – like all tools – arrive in various shades of imperfection, their lack during times of recruitment and appraisal can be costly. This chapter will explore the origins and development of psychometrics, its uses and abuses. It will close by reading the runes of future developments.

Great Men and Their Humour

From when time was in its cradle people have believed that personality traits can be divined. The gift of leadership was particularly prized. Leaders were said to have natural charisma and ability which others instinctively lacked. Even as infants leaders waved their rattles like sceptres (Haney, Sirbasku & McCann, 2011). Thus followers innately looked to trail behind, while women were ‘fitted to be at home as is their nature’ (Buss & Schmitt, 2011). Scientifically illiterate though these ideas may be (Haslam, 2004), moot them in the Red Lion and witness the levels of assent amongst the crowd. The idea of a born leader remains powerfully salient. With due deference to Meir, Thatcher and Merkel, as Carlyle had it (1841, p. 47), ‘The history of the world is but the biography of great men’.

However, even a cursory look at different leaders’ personalities reveals considerable variety within the camps. Alexander the Great’s propensity for megalomania would have sat poorly with Nelson’s service ethic; Kublai Khan’s extravagance is unlikely to have appealed to Karl Marx, while Mahatma Gandhi’s peaceful resistance would probably leave Emperor Hadrian somewhat perplexed. Discussion over the cornflakes would have been tense. And the same differences of approach are found amongst carpenters, midwives and tennis players. So how does any instrument assess for role, aptitude and skill?

Personality and the Four Humours

Many of the chapters of this book will explore how various instruments gauge aspects of personality. Even between the most widely respected psychometric tools the number of perceived personality traits varies widely and runs from five to 32. However, originally there were just four.

It is a matter of conjecture whether a belief in the need for bodily balance was developed by the Indian Ayurveda system of medicine or by the Ancient Greeks. What is certain is that the concept of four distinct bodily fluids – hydraulically interdependent and all influencing human nature – survived from Hippocrates through Galen and the Roman Empire, right through to the Renaissance. Indeed we retain much of the terminology today. To be sanguine, choleric, phlegmatic or melancholy is to echo a system of personality assessment that resonates through the centuries (Figure 1.1).

Figure 1.1 The four humours

A surplus or deficiency of any one of four elemental bodily fluids – or humours – was thought to directly affect one’s feelings and health. All four humours may originate from just one bodily fluid: blood. In the open air blood sedimentation shows a dark, thick clot at its base (black bile), and erythrocytic cells (or red blood) sit on top below a layer of white blood cells which could easily have been labelled as phlegm. Phlegm was not the expectorated gloop we know today. Finally a top pool of yellow liquid (yellow bile) completes the basic substances which were thought to comprise the corporeal human.

An excess of yellow bile was expressed through overt aggression, an issue said to be associated with an agitated liver. Even now we will call somebody who is peevish and disagreeable ‘liverish’ or ‘bilious’, while alternative medicine often insists that anger remains a symptom of a disturbed liver (Singh & Ernst, 2008).

Meanwhile those said to have an excess of what the Greeks called melaina kholé, or black bile, were said to be suffering from ‘melancholy’ or depression. An excess of phlegm was thought to be behind a stolid, fixedly unemotional approach to one’s affairs, and gave rise to the modern phlegmatic personality.

In contrast to the other three humours an excess of blood carried clear personality benefits. People who are sanguine (from the Latin sanguis, ‘blood’) have always been cheerful, optimistic and confident.

Each individual had their own humoral composition, which they shared to a greater or lesser degree with others. This mix of humours precipitated personality in a view that held good from Hippocrates to Harvey via Ancient Rome and Persia. Indeed, this holistic approach is still used in personality type analysis today, where psychometricians are keen to label individuals with marks of similarity (Pittenger, 1993).

Thus, while it is considered pseudo-scientific to tell somebody that they possess a mostly phlegmatic personality (Childs, 2009), you are very likely to hear that you have the temperament of a team worker, or of an introvert, or that you have a blue/green personality. You may even be assigned a group of incongruous-sounding letters such as ENTJ from the globally dominant Myers–Briggs Personality Type Indicator. Amongst other attributes ENTJs are ‘born leaders’ (personalitypage.com, 2015). And we see the ancient terminology being recycled in the twenty-first century, even when it is known to be psychologically flawed. So are some modern interpretations any less pseudo-scientific than their rather longer-lasting forebears (Sipps, Alexander & Friedt, 1985)?

The Beginnings of Modern Psychometrics

The history of psychometrics intertwines with that of psychology. Its modern incarnations have two main progenitors. The first of these concentrates on the measurement of individual differences; the second looks at psychophysical measurements of similarity.

Charles Darwin’s (1809–82) The Origin of Species (Darwin, 1859) explained why individual members of the animal kingdom differ. It explored how specific characteristics show themselves to be more successful and adaptive to their environment than others. It is these adaptive traits that survive and are passed on to successive generations.

Sir Francis Galton (1822–1911) was a Victorian polymath whose panoply of accomplishments encompassed sociology, psychology and anthropology. He was also related to Charles Darwin and was influenced by his half-cousin’s work. Consequently Galton wondered about various adaptive traits in human beings. Not content with merely studying the differences, however, Galton wanted to measure them.

In his book Hereditary Genius (1869), Galton described how people’s characteristic...