A lot of times, people who aren\u2019t numerically-inclined will ask me how advanced stats can help them. It’s tough to come up with a useful response because statistical analysis is as much of an art as it is a science. That doesn\u2019t mean there aren\u2019t some basic things that analytics can do. Separating 2-point percentage from 3-point percentage and offensive rebounding from defensive rebounding are easy places to start.<\/p>\n
But part of the art of analytics is trying to separate the real from the imagined. The thing I want to focus on here is the notion of a shooting slump. In general, people are too quick to throw the S-word around. <\/p>\n
There\u2019s a lot of stuff out there about Baylor\u2019s Brady Heslip and his slump last season. This piece<\/a> from Andy Katz illustrates the perception, and it was a running theme of Baylor-related talk during conference play last season. If you want to use ‘slump’ to describe a player whose shooting percentage decreases from one season to the next, then it applies here as Heslip made 45.5% of his 3’s as a sophomore and 38.6% of them as a junior. But generally I take slump to mean: \u201c[Player] has lost his ability to make shots. He needs to get in the gym and work on his form.\u201d<\/p>\n To that end, I wouldn\u2019t be too concerned about Brady Heslip. Fellow stat-geek Jeff Goodman annually publishes a list of the best shooters in the country during the off-season. This might be his best contribution to the basketball community. Here\u2019s how the top 25 on that list have performed the following season.<\/p>\n That\u2019s actually a pretty good track record there for Goodman and most people would be hard-pressed to do better. (You might, for instance, just try using a list of the 25 most accurate returning 3-point shooters. You\u2019d do slightly worse, though.) The takeaway is that if you\u2019re truly one of the best shooters in the nation, a good guess for your 3-point percentage in the upcoming season is 40%. The average player on Goodman\u2019s list has gone 80-for-200 over the past four years. Heslip went 83-for-215 last season. <\/p>\n But Heslip didn\u2019t just make Goodman\u2019s list, he was ranked second on it. And the higher ranked players tend to shoot better, so we should account for that. I did a quick Excel-style regression that wouldn\u2019t fly in a published journal, but it\u2019ll do the trick here. <\/p>\n Expected 3P% = 41.88-0.916*ln(Goodman Rank)<\/p>\n<\/blockquote>\n Plug in 2 for the Goodman Rank and you get an expected 3-point percentage of 41.2. The players ranked second in prior seasons made 41.4% of their attempts in the subsequent season. Somewhere around 41% would have been a reasonable expectation for Heslip as a junior. In 215 attempts, he would be expected to make 89. (Technically, 88.6.) He made six fewer. That\u2019s hardly worthy of panicking over Heslip\u2019s shot. At least, that shouldn\u2019t be one\u2019s first guess to explain the decrease in accuracy. <\/p>\nSeason 3PM 3PA 3P%\n2010<\/a> 1931 4967 38.9\n2011<\/a> 2015 4985 40.4\n2012<\/a> 1842 4646 39.6\n2013<\/a> 2170 5358 40.5\nTot 7958 19956 39.9\n\n<\/pre>\n
\n