Figure 1.

Response probabilities for paired comparisons in Chinese web survey for respondents included in analysis and respondents who gave inconsistent answers to the test re-test questions. Colors on the heat maps correspond to the probability that the first health state in a paired comparison was chosen as the healthier outcome. Variation in the amount of measurement error across surveys is reflected in the varying degrees to which response probabilities follow an orderly transition from high to low between the upper left and the lower right corners in each heat map. A heat map with no measurement error and high internal consistency indicated by a smooth color transition from blue to red along the diagonal, whereas a heat map with a high amount of error would have a random assortment of colored squares. a. Heatmap of PC answers by 468,541 respondents who consistently answered the test re-test questions; b. Heatmap of PC answers by 169,890 respondents who consistently answered the test re-test questions inconsistent answers.