Are you playing against actual people or AI generated "people"?

I would say they are AI generated. I noticed that I play to 1st place, sometimes in the middle of the night and the players in 2nd and third place scores keep growing but staying just behind me. Then I sleep a few hours, get up, and start playing again. Their scores have not gone up. As soon as I start playing their scores start to rise again. What are the chances that 2 other people in the world are going to be going to bed, getting up, and playing at the exact time I do? Slim to none. Especially not everytime.

I would agree. After months of frequent play for long periods of time to remain on top, I now realize the gaming competitors have not progressed beyond me in my absence! The site is not managing any legitimate personal tracking and goes in and out of logical patterns of control. It must exist really to support ads which become progressingly difficult to overcome. I play it for pure personal satisfaction at the end of the day and cannot trust it to actually track any personal progression or reward gains like legitimate games. It probably is no where near as challenging as playing real mahjong.

I totally agree. I am convinced they are AI generated, but still get drawn in and play more games than I would if there were no other 'players'. It is a clever strategy.