On broad terms, music that is more "upvoted" tends to be selected by the "DJ" more often, but we use a trend predection algorythm to weight the selection. Thos

On broad terms, music that is more "upvoted" tends to be selected by the "DJ" more often, but we use a trend predection algorythm to weight the selection. Those are not the only criteria for selection, but its the most decisive. We assign "points" to the different criteria and then rank the next best song according to that index.