Open vs. 299 Daylongs

[gjfeldman]

A few weeks ago, the ACBL 299er daylong tournaments appeared. I wondered whether one would do better playing open daylongs or the new 299er, so I randomly selected 400 results for the C stratification from MP-1 and 299er daylongs. The results are shown below in a plot of masterpoint reward vs. percentage score. The blue dots are for MP-1 and the red dots are for 299er. In both cases, about 45% of the results get zero masterpoints.

 

 

The first thing you notice is that there is a large range of rewards for each percentage score. The ACBL does this on purpose through sectioning and a hidden metasectioning so that the stronger players do not gobble up all the masterpoints leaving weaker players discouraged. This is generally accepted since it all averages out in the end.

 

However, for a given percentage score, the 299er rewards are less than the MP-1 rewards. The dotted curve is a third order polynomial fit to the data, showing that to get a particular award it is necessary to score about 5 or 6 percentage points higher in a 299er tournament than an MP-1 tournament. But my experience is that, on the average, I do score about 5 or 6 percentage points better in 299er tournaments. I think that this expectation may vary for different individuals depending on their skill level and their stratification level in both types of tournaments.

[mycroft]

299er club games are rated for top-flight overall as 80% of open club games. Because you should expect to do significantly better when the more experienced players are removed from the game.