In communication research scales are used to assess the intensity or the strength of personal variables like traits, states, attitudes, feelings, and so on. A rating is based on a statement expressing a perception, an attribution, or an attitude toward something that is presented to the subject. He or she is asked to indicate the degree of his or her agreement with this statement by marking a corresponding label from a list provided by the scale. Bipolar Likert scales (Likert 1932) extend from negative to positive numbers (e.g., −2 to +2), whereas unipolar Likert scales start from non-negative numbers like 0 or 1 (e.g., +1 to +5). Likert scales are most frequently constructed as five-point scales, but scales with seven or even nine points are also common. The labels assigned to points on a Likert scale (like “strongly disagree,” “somewhat disagree,” “neither agree nor disagree,” “somewhat agree,” “strongly agree”) must be chosen with great care in order to hold up equal semantic distances between the labels over the entire scale. As it cannot be ensured that subjects perceive intervals between adjacent points on the scale as equidistant, responses collected from subjects should preferably be cautiously treated as ordinal (and not as interval) data.
A Guttman scale (Guttman 1950) is constructed in such a way that category items are strictly ordered according to their difficulty. For that reason it is assumed that a person agreeing with the label assigned to point 7 on a Guttman scale implicitly agrees to all items with lower numbers (i.e., 1 to 6) too. Guttman scales are helpful in constructing short questionnaires with good discriminative power. Furthermore, a semantic differential consists of a set of rating scales designed to measure the connotative meaning of concepts. End points of the scales building up a semantic differential are labeled with contrastive adjective pairs like “warm–cold” or “weak–strong.” Factor analyses (Osgood et al. 1957) revealed three factors – activity, evaluation, and potency – underlying ratings of objects on the semantic differential.
In communication research, scales are predominantly applied to access subjects’ personality traits that are related to program selection and media use, or to measure the intensity of personal reactions that go along with or follow the reception of media. For example, the tendency to seek arousal and excitement is correlated with a preference for viewing action or horror films. For the measurement of this personal disposition, Zuckerman (1994) has developed the sensation-seeking scale (SSS). The need for cognition has been demonstrated to be a predictor of program selection and the intensity of attentive media processing. This motivational trait can be measured with a scale provided by Cacioppo et al. (1984). For the measurement of emotional states evoked by media presentations (e.g., action films, dramas), questionnaires like the Self-Assessment Manikin (SAM; Lang 1980), the Positive and Negative Affect Schedule (PANAS; Watson et al. 1988), or the Differential Emotion Scale (DES; Izard 1972) are appropriate.
When interpreting data collected with scales, it must be taken into account that the subjects’ reaction might be distorted by response biases. As a further drawback especially relevant in communication research, scales can hardly be applied for the continuous measurement of response variables. For example, for the continuous assessment of emotional processes during media reception, alternative methods like the physiological measurement or the analysis of facial expressions should be chosen to complement data collected with scales.
References:
- Cacioppo, J. T., Petty, R. E., & Kao, Ch. F. (1984). The efficient assessment of need for cognition. Journal of Personality Assessment, 48, 306–307.
- Guttman, L. (1950). The basis for scalogram analysis. In S. A. Stouffer, L. Guttman, E. A. Suchman, P. F. Lazarsfeld, S. A. Starr, & J. A. Clemsen (eds.), Measurement and prediction. New York: John Wiley, pp. 76–77.
- Izard, C. E. (1972). Patterns of emotions. New York: Academic Press.
- Lang, P. J. (1980). Behavioral treatment and bio-behavioral assessment: Computer applications. In J. B. Sidowski, J. H. Johnson, & T. A. Williams (eds.), Technology in mental health care and delivery systems. Norwood: Ablex, pp. 131–170.
- Likert, R. (1932). A technique for the measurement of attitudes, Archives of Psychology, 140, 1–55.
- Mangold, R., & Brenner, K. (1999). Information auf allen Kanälen? Zum Einfluss des Kognitionsbedürfnisses auf die Tendenz zum Umschalten. Rundfunk und Fernsehen, 47, 499–514.
- Osgood, C. E., Suci, G., & Tannenbaum, P. (1957). The measurement of meaning. Urbana, IL: University of Illinois Press.
- Rohrmann, B. (1978). Empirische Studien zur Entwicklung von Anwortskalen für die sozialwissenschaftliche Forschung. Zeitschrift für Sozialpsychologie, 9, 222–249.
- Watson, D., Clark, L. A., & Tellegen, A. (1988). Development and validation of brief measures of positive and negative affect: The PANAS scales. Journal of Personality and Social Psychology, 54, 1063–1070.
- Zuckerman, M. (1994). Behavioral expression and biosocial bases of sensation seeking. New York: Cambridge University Press.