AND ITS VARIOUS DEVICES. Attitude is such an abstract, complex mental set. up that its measurement has remained controversial.

Transcription

1 CHAPTER III attitude measurement AND ITS VARIOUS DEVICES Attitude is such an abstract, complex mental set up that its measurement has remained controversial. Psychologists studied attitudes of individuals but such studies were more of a qualitative nature rather than quantitative ones. The rise of Psychometrics provided enough instruments to construct psychological tools. Intelligence, aptitudes, interests, achievements were begun to be measured quantitatively through suitable tests. Psychometricians devised suitable techniques to measure attitudes also. Scientific treatment to attitudes requires quantification. Attitude scales began to be devised which could assess attitudes in a quantitative manner. The attitude scales may be classified according to methods of constructing attitude measuring'devices. These devices are - (a) Priori Scales. i (b) Psychophysical Scales. (c) Sigma Scales. (d) Master Scales, etc. above devices here. It would be worthwhile to explain in brief the

2 (63) (a) Priori Scales : The crudest method of measuring attitudes is that of the case method, closely followed by ballot counting, as exemplified in various public opinion polls. Such devices are in fact two-point " Scales* " The proportions of *yes* and *no votes are taken as an index of the existing social attitude for a given population. (b) Psychophysical Scales : The method of such scales consists of arranging a series of opinions relevant to a given attitude object, ranging all the way from most favourable to most unfavourable, in equally spaced, experimentally determined units along a continuum. (c) Sigma Scales s These scales are constructed on the assumption that attitudes are distributed normally. The attitudes are measured using standard deviation units* The method is criticised on the ground that it makes the doubtful assumption of normality of distribution. And such findings do not warrant discarding the judging group, especially if measurement of individuals rather than groups is desired.

3 (64) (d) Master Scales i It Is a device in which the statements of the scale do not refer to a particular attitude object but they are stated in a general form. Such scales are largely devised as they can be useful for various attitude objects. Of the above scales, Thurstone s H technique of Equal-appearing intervals ","The method of Paired Comparisons "»"The Method of successive interval " and Likert's " Method of summated Ratings " are largely used. The first three techniques belong to Psychological scales and the last one belongs to Sigma Scales. Techniques The Method of Equal-appearing intervals : The method of Equal-appearing intervals as developed by Thurstone and his associates is derived from psychophysical techniques. It seeks to arrange people on a continuous scale having equal-appearing units- The procedure is as follows : There are three main steps in this technique - 1. Preparation of possible items, 2. Sorting out by judges and 3. Testing for relevance. In the beginning a large number of simple statements which

4 (65) express some kind cf opinion about the attitude object under study are collected.. Possible statements are obtained by collecting opinions from writers and laymen reflecting all shades of belief. These items should cover the entire continuum of attitude toward the object in question, from extreme unfavourable on the one hand to extreme favourable on the other. Each item is placed on a slip of paper. The entire pack of slips is then given to a judge who places the slips in eleven piles, ranging from one extreme to the other in approximately equal steps. This is the reason for the name " method of equal-appearing intervals." The equal intervals are differences in attitude that appear equal to the judges. ', After a statement has been.scaled by a number of judges, it is discarded if judges disagree markedly in sorting out it.for statements retained, the. scale value is the median position assigne \ by the judges. To give an idea of the spread of the distribution scale value (S) the about the^inter-quartile range (Q) is also calculated'. This Q may be regarded as a measure of ambiguity of a statement and thus will give an objective criteria for eliminating unsuitable items. The statements chosen are then placed in a preliminary check list. This list is given to subjects as a means of checking the relevance of items. The scores of those who check a given item are tabulated. Items which are frequently checked by people whose, attitude score is far from the scale value of the item are discarded. /

5 (66) The final scale consists of items which have passed the tests for ambiguity and relevancy. Final items are selected to represent the entire range of attitudes* The Method of Paired Comparisons : A particularly sound technique, the paired comparison method, has received less attention than it deserves. The subject is given the paired terms, each term being paired with another term. The subject marks the preferred member of each pair. From these judgements, one can reconstruct with great reliability the rank order of preferences and can determine a scale-value or acceptance score for each group. Paired comparisons have the advantage of being precise, free from response sets and relatively hard to falsify, since each item demands a response. The weaknesses of the method are that it is time consuming and it does not measure what each person believes about each stimulus, as it measures relative preferences only. Suitable adaptation of the method might overcome this difficulty. The Method of Successive Intervals : This method, like the method of equal**appearing intervals, requires but a single, judgement from each subject for each statement to be scaled. It is, therefore, a convenient method to use when the number of statements to be scaled is large.

6 (67) Any of the judging methods as described in the method of equal-appearing intervals may be used. Data will be in the same form. For each statement there will be a frequency distribution showing the number of time that the statement has been placed in each of the successive intervals. These frequencies may be cumulated, from left to right, and the cumulative frequencies may be expressed as cumulative proportions by multiplying each one by the reciprocal of the number of judges. The scale values of the statements may then be taken as the medians of the corresponding cumulative proportion distributions. Tie further procedure is same as it is in the method of equal-appearing intervals. The Method of Summated Ratings : This method generally associated with the work of Rensis Likert, is an application to attitude scaling of item-analysis procedures borrowed from test-construction techniques. The fundamental steps are as follows : First of all as in the case of method of equalappearing intervals, a large number of statements relating to the attitude object in question are collected. These items are to be carefully edited by the investigator to eliminate ambiguous, irrelevant, and otherwise faulty items.

7 (68) The items are then drawn up in the form of a questionnaire or attitude test, each item being given multiple response categories of " Strongly agree, agree, undecided, disagree, strongly disagree. n The statements should be so constructed that for half of them an " agree " response represents a favourable attitude toward the attitude bject in question, and for the other half a " disagree " response represents a favourable attitude. This experiment instrument is then administered to a reasonably large group of subjects and asked to indicate their own attitudes by checking the response to each item which most nearly expresses their feeling on that item. The subject indicates his reaction to each statement usually on a five point scale. These answers are credited 5, 4, 3, 2 and l respectively for favourable statements and 1, 2, 3,4 and 5 respectively for unfavourable statements. A favourable attitude is shown in a high score. A subjects score is the sum of the weights assigned to the responses which he has made. The items are then analysed for their discriminatory power with respect to measurement of the attitude in question, by any one of the several item-analysis procedures available. Perhaps, the simplest index is to take the top and bottom 27 per cent of subjects on the distribution of total scores, and calculate the mean of the responses to each item for each of these groups separately. Those, items are the most

8 (69) discriminating which show the greatest discrepancy in mean response between high and low extreme groups* The final attitude scale is then constructed by choosing the twenty to twenty-five statements from the total list which show the greatest discrimination. These items are used with the same five agree-disagree response categories* and scoring is done in the same *iay. Comparison of Testing Techniques Several investigators have tried to establish the comparative merits of the Thurstone and Likert techniques. Since corresponding scales of the two types have high correlations, there is little difference except in convenience. For most purposes, the general conclusion is that it matters little which method is used. The time required to construct a Thurstone type scale is a drawback. Careful construction of a Likert type scale requires about half the time needed for the Thurstone procedure. The factors which make for invalid self-report are equally present in both tests. The Likert Method permits response sets to influence the score, which might lower validity, whereas directions for the Thurstone scale require one to check say, the six statements with which he most agrees, no response sets affect the score.

9 \ (70) In equal-appearing interval scales, the attitude score obtained by a single subject has an absolute interpretation. That is because the attitude score is taken as the Median of the scale values of the statements with which the subject agrees. Thus the interpretation of an attitude score on an equal-appearing interval scale can be made independently of the distribution of scores for a particular group Of subjects. Whereas, the interpretation of an attitude score on a sumraated rating scale cannot be made independently of the distribution of scores of some defined group. The summated rating score corresponding to zero or neutral point on a favourable unfavourable continuum is not known; as it is assumed to be known in the case of equal-appearing interval scores. Nor is there any evidence to indicate that the neutral point on a summated rating scale necessarily corresponds to the mid-point of the possible range of scores, i.e. to the score of 50 on a 25 item scale. Scaloqram Analysis It differs considerably from the methods of constructing attitude scales that have been previously described. In one sense, it is not a method for constructing or developing an attitude scale, although it has been referred to as such by other writers. It is referred as a Guttman Scale or a Cumulative Seale, as it is set forth in some detail by Guttman.

10 The question arises about a proper criterion for unidimensionality of a scale. Guttman, who is principally responsible for the theory and techniques of " Scale analysis, has proposed the following,^ If a single quantitative score is to represent, without ambiguity, the behaviour of an individual on a large group of items, we must know the individual's score, to know his behaviour on each and every item in the group, Guttn*an has called this as the principle of reproductivity. Method used in the Present Scale The method adopted in present scale is based on Thurstone's Technique of Equal-appearing intervals. Though laborious, the method certainly possesses an advantage over the other techniques in so far as it helps to assign a quantitative score to each of the statements contained in the scale. The detailed planning of the investigation is described in the next chapter. 1 i Guttman, Louis : A Basis for Scaling Qualitative Data " American Sociological Review, 1944, pp

11 (72) SELECTED REFERENCES 1. Edwards A.L. : Techniques of Attitude Scale Construction i New York, Appleton-century Crofts, Inc., 1957, Ch. II-VII. 2# Remmers H.H. : Introduction to Opinion and Attitude Measurement : New York, Harper Brothers/Ch. IV, Pp , Greene H.A., Jorgensen A.N. and Gerberich J.R. : Measurement and Evaluation in the Elementary School : New York, Longomans Green and Co. 1953, Pp Guttman, Louis : A Basis for Scaling Qualitative Data t American Sociological Review, 1944, Pp Downie N.M. i Fundamentals of Measurement Techniques and Practices : New York, Oxford University Press, 1958, Ch. j.6, Pp Remmer H.H. and Gage N.L. : Educational Measurement and Evaluation : New York, Harper and Brothers, 1955, Ch. XIV, Pp