Web-based versus controlled environment psychophysics experiments
Silvia Zuffi, Paolo Luigi Scala, Carla Brambilla, Giordano B. Beretta · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2007
A recent trend in psychophysics experiments related to image quality is to perform the experiments on the World Wide Web with a large number of observers instead of in a laboratory under controlled conditions. This method assumes that the large number of participants involved in a Web investigation "averages out" the parameters that the experiments would require to keep fixed in the same experiment performed, following a traditional approach, under controlled conditions. In this paper we present the results of two experiments we have conducted to assess the minimum value of color contrast to ensure readability. The first experiment was performed in a controlled environment, the second on the Web. The result emerging from the statistical data analysis is that the Web experiment yields the same conclusions as the experiment done in the laboratory.