“…First, as with any other study on sex workers, data on this type of work are generally selected in the sense that census-type data on sex workers are not available. Data will not be available unless sex workers are willing to participate in a field study (as in [1,4,8,10,20,22]) or they come forward with an online posting and deliver information without knowing (as in this study and also in [7,18]). Second, as opposed to ''offline'' sex workers, ''online'' sex workers as used in this study tend to be better educated, financially less dependent, and part of the higher price segment of the market (see Cunningham and Kendall [6]).…”