Category scale

Stevens, S.S., and Stone, G. (1959). Finger span Ratio scale, category scale and JND scale. J. Exp. Psychol, 57, 91-95. 

The third dimension is the hedonic tone, or the category of judgement of the relative like (pleasantness) or unlike (unpleasantness) of the odour. That is an emotional level of reaction which is assessed in accordance with a given category scale, from "extremely unpleasant" to "extremely pleasant" (see for example VDI guideline 3882-... 

Reiners et al. employed a sensory analysis to check whether the results of the instrumental analyses were in agreement with their flavor profiles. The sensory panel used, consisted of nine experienced assessors, seven males and two fanales, aged 25-35 years. The sample was sniffed by the panelists (nasal evaluation) and then rinsed into the mouth (retronasal evaluation). The intensities of the odor characteristics of the olive oils scored as above on a category scale from 0 to 3.0. After an outlier test, the results were expressed as means (standard deviations). Apple-like and green notes were characteristic for the Italian oil, whereas the Spanish oil smelled intensely like black currants and the flavor of the Moroccan oil came close to eating black olives. Olive oils of several types and cultivars were sensory evaluated for main attributes by various composition panels giving important results. 

At present, the use of ME ratio scaling is both in a state of expansion and critical evaluation. The technique has been found to serve well for attitude evaluations (such as the impact of an advertisement). ME in combination with a response surface experimental designlZ has been used for optimization of food products. Ratio scaling is still experimental in that a best normalization method has not been found, nor has the method received a critical comparison to the more popular category scaling method. Both of these questions are now being addressed by the American Society for Testing and Materials (ASTM) Committee E-18 - Sensory Evaluations of Products and Materials. 

Proponents of ME claim the method to be easy to teach to naive panelists, very sensitive for measurement of intensities in the supra-threshold region and very efficient for measurement of product preference relative to some bench mark. The future of the method will depend on how it stands up to a critical comparison with category scaling methods. 

Figure 6 Body Discomfort Map. Maps can have more or less detail this map includes the foot but other maps may emphasize the arm or hand. The worker gives the amount of discomfort at any location. One discomfort scale is the Borg category scale (CR-10) shown in the figure. The CR-10 scale gives 0.5 for extremely weak and 10 for extremely strong people are permitted to go below 0.5 and above 10. Body discomfort maps are a popular technique of getting quantified input from operators. (From Corlett and Bishop 1976)...

White American military personnel for selected desserts and beverages. Modified from Meiselman (1977). Hedonic ratings based upon 9-point category scale developed by Peryam and Pilgrim (1957). 

Ordinal scale Samples are ranked for a single specific characteristic. Ordinal data are used for category scaling . The tasters are asked to rate the intensity of a sensorial stimulus by assigning a score on a limited verbal or numerical scale. The number of points on the scale used for the determination of the different flavor attributes can differ by 5, 7, 9, and 10 points. Usually a description is attached to each value. In this scale the data are merely ordinal and intervals are not equidistant. The size of the difference between two values cannot be assumed to reflect the difference between the perceived intensities. 

Hedonic scaling can be achieved using a five-, seven-, or nine-point scale. Such category scales are based on nonequal interval spacing, and for this are treated as ordinal scales. An alternative approach is to ask respondents to indicate their hedonic response... 

Kim, K. and O Mahony, M. (1998). A new approach to category scales of intensity I traditional versns rank-rating. Journal of Sensory Studies, 13, 241—249. 

In this example, the consumers are asked to rate both their perceived and ideal intensities on a 100 mm line scale, with anchor points at 10 and 90. No restrictions concerning the scale used are given, except that it should be identical for both the perceived and ideal intensities. Additionally, the consumers are asked to rate the products on liking. Specific liking questions can also be asked. For hedonic questions, a 9-point category scale is used. 

Children aged 8-9 were shown to be able to estimate the intensity of sweetness in a suitable way compared to adults, by comparing category scale, magnitude estimation and hand separation (James et al, 2003). A nine-point scale was successfully applied to the evaluation of the intensity of sweetness and creaminess in children aged 8-10 and 11-14 years, but the researchers used pair comparisons to evaluate perceptions in children aged 5-7 years (Lavin and Lawless, 1998). A five-point scale was used to describe perception of sweetness intensity throughout the age span from 6 years ... 

Finally, as regards the choice of scale, Doty (1991) argued that the simplicity and robustness of category scales make them very appropriate to elderly studies. In fact, in the study described in Section 23.4, it was observed that older subjects were using a seven-point hedonic scale in a repeatable and discriminative way. In Kremer et al. s study (2007), evaluations were made from visual analogic scales. All the previous... 

Borg, G. (1982). A category scale with ratio properties for intermodal and interindividual comparisons.. In Petzold, H. G. G. A. P. (ed.) Psychophysical Judgment and the Process of Perception. Berlin Deutscher Verlag der Wissenschaften. 

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