In this third installment of "Useful Basketball Stats" I wanted to present an easy to understand and very easy to implement 21st century stat. This is called EFFECTIVE FIELD GOAL PERCENTAGE. Everyone understands basic Field Goal (FG) % because it is just the total number of field goals made (FGM) out of total field goals attempted (FGA) so FG% = FGM/FGA........as easy as it gets so far. The one thing about the sport of basketball, and in this case specifically, field goals (excluding foul shots) there are two point values for field goals: 2 and 3. In soccer you don't get an extra point or goal if you score outside of 25 yards, it's the same to tap it in the net vs. blast a goal-kick into the opposing net. However, in basketball the area outside the arc accounts for one more point. Armed with this information there is a better way to understand your shooting average on field goals.
The reason eFG% tells a better story than FG% is that it takes into consideration that the 3pt make is worth 50% more than the 2pt make. The formula is: eFG% = (FGM+(0.5 x 3PM))/FGA ------ 3PM = number of 3pt shots made If you do not shoot any threes at all your FG% = eFG% and if you make 3pt shots than the formula gives you credit for it. FG% doesn't tell you enough because a 2ft shot is far different than a 22ft shot, and they shouldn't be valued the same. If the math and short Excel formulas scare you just think, it's still just makes/shots taken, but add (0.5 x 3PM) to your total makes. Hope this helps and gives you an understanding, having a shot chart with percentages shown from different spots on the floor is another useful way to differentiate FG% from different areas. Then as I said in a previous post you can also start to get specific with %s on contested vs. uncontested shots and start to get some answers about your offense. If you end up shooting a lot of contested shots in your offense maybe you need to investigate why. For your specific team what kind of shots do you want from what particular spots? What will put your best players in the best positions to succeed? All good questions to reflect on before, during, and after your respective seasons. Thanks for reading!
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In this second installment of useful basketball stats, I wanted to include a metric which isn't quite so familiar to people. Usage rate combines various values in a typical box score to estimate the number of team plays which are "used" by an individual player in the minutes they played. The values used in this estimate are rooted in the typical end of a possession which ends in three possible ways: a turnover, a field goal, or a free throw. Comparing these values, both team and individual, along with factoring in minutes played bring you the Usage Rate.
The formula is: 100 * ((FGA + 0.44 * FTA + TOV) * (Tm MP / 5)) / (MP * (Tm FGA + 0.44 * Tm FTA + Tm TOV)).
In an NBA example the leader in USG% last year 2016/2017 was Russell Westbrook at 41.7% So Westbrook used 41.7% of all the total possible plays in a game. These is obviously easy to understand qualitatively because Westbrook averaged a triple-double and was the at the center of all the action for the Thunder. In a more relatable example for all levels of basketball......in my team's final game of the first semester my starting point guard had a great line of 18 pts, 8 rb, 8 ast - shooting 60% from the field, and playing 31 minutes. Her USG% that game was 22.1% So when she was on the floor she was involved in that percentage of the teams plays. The weakness of this stat is that it does not include assists in usage terms. You could have a player who fought for a rebound, dribbled through 3 people, and layed a drop pass to a teammate for a layup but technically she didn't "use" that play by this metric. There are other tools to compare this stat against such as Assist% and Offensive Rating which help to paint a clear picture about player effectiveness and efficiency. These analytics are tools, not silver bullet solutions, but they certainly tell you a lot more than a typical box score! Some great resources for getting familiar with advanced stats and analytics are:
This is post is the first in a small 4-part series I am writing up to discuss basketball statistics, analytics and the useful application of different easy stats. Box-score stats really do not tell much of a story, but hopefully some of the ideas I am going to discuss will help to create a better narrative of what really happens in a game and over the course of a season.
The stat we are going to look at for Part 1 is a measure of offensive and specifically shooting efficiency. This stat is painfully simple but drills down to an essential focus on shooting efficiency. Pts/FGA is the stat. It is easy to understand and implement, It takes into account the fact that 3pt shots are worth more than 2pt FG's, so it inherently considers 3P%. It is different than the widely used Points Per Possession because instead of valuing each possession separately (maybe you fired up a few bad shots but got the offensive rebound to extend the single possession) it considers EVERY shot and the quality of them. Similar to Points Per Possession the more free throws you make the higher your Pts/FGA will be. This stat is a great lens to look at team scoring efficiency from game to game, but it is also extremely useful in looking at individual player efficiency and effectiveness. If you have a player shooting lots of tough, contested jumpers (and not getting to the FT Line) it will show through in this stat very clearly. Perhaps the most powerful application of this stat which I call "scoring efficiency" is to match it with charting shot quality. Many teams have rating systems for their shots; tagging a number to a specific shot type (I've seen this done several ways) for example: Open Layup = 9, Wide Open 3 - 7, Wide Open 2 (outside key) - 5, Contested 2 (outside paint) = 3, Contested 3pt = 2. You can play around with the valuing system to suit your concepts and style of play. Without over-complicating things (a common fault for me) it would be hugely beneficial for teams to simply start tracking Open vs. Contested Shots, and then perhaps tagging onto that where on the floor these came from. That by itself would tell you a lot. For a great (and well linked article on this see: http://articles.basketballogy.com/2012/your-shot-chart-is-lying-to-you-and-what-to-do-about-it/ Credit for the Pts/FGA stat and the first place I saw it to Ben Taylor in his book "Thinking Basketball." Stay tuned for Part 2 next week! FOOTNOTE: As noted in Taylor's book Pts/FGA is the same stat as True Shooting%, (TS% just arranges the numbers in the form of a percentage). I would contend that Pts/FGA is a more tangible, easier to understand stat for players/coaches than True Shooting%. The simplicity of the stat combined with all the contributing factors that can go into "Pts" and "FGA's" can make for clear comparisons and easy application. |
AuthorCoach Matt - Father, Coach, Life Long Learner, Basketball Addict Archives
June 2020
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