Bannister repertory grid

The Repertory Grid is an interviewing technique which uses factor analysis to determine an idiographic measure of personality. It was devised by George Kelly in around 1955 and is based on his Personal Constructs theory of personality.

Introduction
The repertory grid is a method of assessing personality that consists of two parts. The first part is determined by the interviewee whose personality is being assessed. The interviewer asks the person to list a number of people in their life, such as:


 * Mother
 * Father
 * Best Friend
 * Partner
 * Admired Male
 * Admired Female
 * Disliked Male
 * Disliked Female

There is no limit as to how many people may be listed, but for practicality it is usually between 7 and 20 persons.

The person being assessed is then asked by the interviewer to place the listed persons into groups of three (normally determined by the interviewer) and to invent a descriptive factor to distinguish one person in the group from the other two.

For example; for the group: Mother-Father-Disliked Male, the interviewee may choose the factor 'aggressive' to distinguish the disliked male from his or her 'non-aggressive' parents.

Other factors may include:


 * 'Good -Bad'
 * 'Expensively dressed - Modestly dressed'
 * 'Less than 10% return on investment - More than 10% return on investment'
 * 'Creative - Dull'
 * 'Friendly - Remote'
 * 'Friendly - Aggressive'

These factors can be termed constructs which are the basic units by which people ascribe meaning to their experience. Every construct consists of a contrast, rather than a simple 'opposite' (If all that were offered was an opposite, e.g. 'Friendly', the exact meaning of 'Friendly' would not be discernible, as it is in the last two examples).

Once factors have been determined for each of the triad groups, each person on the interviewees list is rated on a scale of 0-10.

Using the Repertory Grid
To illustrate the last two steps by means of our example. Constructs are elicited as follows. The interviewee is asked to compare three of the elements (e.g. three of the colleagues in our example, 'Tom', 'Peter', and 'Mary'), and state which of them have some characteristic in common while being different from the third. The interviewee might respond that Tom and Mary are alike because they are keen and committed to their job while Peter is different because his energies seem to be conserved for life outside the job. So 'Keen and committed, versus Energies elsewhere' has been identified as a construct; one way that the interviewee has of construing (thinking about, giving meaning to) his or her colleagues at work.

The elements are then characterised in terms of the constructs. Typically, this is done by means of a 5-point rating system, a 1 indicating that the left pole of the construct applies ('Keen and committed') and a 5 indicating that the right pole of the construct applies ['Energies elsewhere'). On being asked to rate all of the elements, our interviewee might reply that Tom merits a 2 (fairly keen and committed), Mary a 1 (very keen and committed), and Peter a 5 (his energies are very much outside the place of employment). The remaining elements (another five people in our example) are then rated on this construct.

A different triad is chosen, a further construct elicited, and all elements rated on this new construct. And so on, until the interviewee indicates that s/he can think of no other constructs. Typically, (and of course depending on the topic) people have a limited number of genuinely different constructs for any one topic: 6 to 16 are common when they talk about their job or their occupation, for example. The richness of our meaning structures comes from the many different ways in which a limited number of constructs can be applied to individual elements. We might discover that Tom is fairly keen, very experienced, lacks social skills, is a good technical supervisor, can be trusted to follow complex instructions accurately, has no sense of humour, will always return a favour, and only sometimes help his co-workers; while Mary is very keen, fairly experienced, has good social and techncial supervisory skills, needs complex instructions explaining to her, appreciates a joke, always returns favours, and is very helpful to her co-workers. Two very different and complex vignettes, using just 8 constructs about one's co-workers.

Analysis of Results
Intersting and important information can be obtained by including self-elements such as 'Myself as I am now'; 'Myself as I would like to be' among ther elements, where the topic permits.

A single grid can be analysed for both content (eyeball inspection) and structure (cluster analysis, principal components analysis, and a variety of structural indices relating to the complexity and range of the ratings being the chief techniques used). Sets of grids are dealt with using one or other of a variety of content analysis techniques. A range of associated techniques can be used to provide very precise, operationally defined expressions of an interviewee's constructs, or a detailed expression of the interviewee's personal values, and all of these techniques are used in a collaborative way. The repertory grid is emphatically not a psychological 'test'; it is an exercise in the mutual negotiation of a person's meanings.

The repertory grid has found favour among both academics and practitioners in a great variety of fields because it has one unique characteristic. It provides a way of describing people's construct systems (loosely, understanding people's perceptions) without prejudging the terms of reference.

Unlike a conventional rating-scale questionnaire, it is not the investigator but the interviewee who provides the constructs on which a topic is rated. Market researchers, trainers, teachers, guidance counsellors, new product developers, sports scientists, and knowledge capture specialists are among the users who find the technique (originally developed for use in clinical psychology) helpful.