alternative. This implies that the observed response unintentionally deviates from the response the user intended to give.
To prevent this in the administration of the USQ, a slider (see also ITU-R BT.500-7 Rev. 1995) is presented to the users. Users can mark their response on the slider exactly at the place they want and are no longer forced to select a response from a limited set of discrete responses. The distance between the left side of the scale and the mark that the user made on the scale is considered to be the quantification of the response. Currently a clustering algorithm is being developed to counteract the noise in the data that is introduced by quantifying responses at a higher resolution than is used by the respondent.
The results so far in the development of the USQ are promising. A series of tested items that have proven to work under various circumstances is available. If the remainder of the development of the USQ is cast in the framework of IRT, the questionnaire becomes a flexible tool that can be adapted to the needs of the researcher to assess users' satisfaction. Eventually the scope of consumer electronics products may be broadened to encompass other domains in the item bank as well.
The users are also equipped with flexible means to contribute to the satisfaction measurement. By letting the user mark their opinion on a slider, a continuous rating scale, the researcher allows them maximal freedom, thus enhancing the validity of the test results.
De B. E.R. Ruyter, & Hollemans, G. ( 1998). Towards a User Satisfaction Questionnaire for Consumer Electronics: Theoretical Basis [NL-TN 406/97]. Eindhoven: Nat.Lab. Philips Electronics N.V.
Hollemans, G., & De B. E.R. Ruyter ( 1998) Selection of Items for the User Satisfaction Questionnaire. Eindhoven University of Technology: IPO-report 1185.
ITU-R Recommendation BT.500-7 (Revised) ( 1995). Methodology for the subjective assessment of the quality of television pictures.
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