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03-30-2011, 10:09 AM   #16
Yao Ming's Foot
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Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by Micku Exactly. And if a team has more possessions, it usually leads to more scoring across the board.

But has no impact on the def rating

Game 1

50 pts scored over 50 possessions

Game 2

100 pts scored over 100 possessions

= 100 DEF RATING

03-30-2011, 10:12 AM   #17
Calabis
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Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by Micku It does make it unfair. Because it is proportional the number of possessions. If the possessions are higher, then the defensive rating goes higher. Since possessions also adds the amount of FGA, it is unfair to compare a league who averages less possessions than a team that averages more possessions. It doesn't work that way. And with the 2nd one "While the 2nd example had the less amount of possessions, but scored the same amount of points." Sorry for the typo. --- And I see what you did. Usually there are more possessions, the team scores more. This also adds into pacing. When you put in a team who average 75 possessions and allowed 100 points, it showed bad defense than a team who allowed 100 points with 100 possessions. That 75 possessions team would have a very high FG% rating probably, or just kept scoring like mad. It doesn't work that way though. Usually more FGA means more chances for FG make. And since the FG of the 80s were in the 50% or above, it also shows that it's inflated.

Hope u have time, he doesn't understand how pace factor affects defense, he doesn't understand that having 13 to 14 more possessions, tends to equal more points, which when plugged into the formula, results in higher D rating....

hence Phila posting and adjusted D rating(to pace) in one of his YLF threads that resulted in a 91 DRating

03-30-2011, 10:15 AM   #18
Yao Ming's Foot
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Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by Calabis Hope u have time, he doesn't understand how pace factor affects defense, he doesn't understand that having 13 to 14 more possessions, tends to equal more points, which when plugged into the formula, results in higher D rating.... hence Phila posting and adjusted D rating(to pace) in one of his YLF threads that resulted in a 91 DRating

Jesus Christ you kids are dumb these days. Do you understand division?

Points Scored in the Game
--------------------------
# of Possessions

If you increase the denominator in a fraction does the value you get go up or down.

03-30-2011, 10:26 AM   #19
Micku
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Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by Yao Ming's Foot But has no impact on the def rating Game 1 50 pts scored over 50 possessions Game 2 100 pts scored over 100 possessions = 100 DEF RATING

Yes it does.

More possessions means more chances of scoring and more chances of defending. Especially if you take into account of pacing and how good the offense is.

What you are doing is showing a point per possession, which is fine. But you are demonstrating a game which everybody shoots decent % in FG. This is fine, and you're right that it wouldn't have an affect if anything stays the same.

However with more possessions, the offense get a chance to attack more, and will probably make it. If not, then their FG% may stink. FGA means more chances of points. FG% is the likely of that point, which is why comparing the eras would matter and probably will be invalid.

03-30-2011, 10:41 AM   #20
Yao Ming's Foot
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Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by Micku Yes it does. More possessions means more chances of scoring and more chances of defending. Especially if you take into account of pacing and how good the offense is. What you are doing is showing a point per possession, which is fine. But you are demonstrating a game which everybody shoots decent % in FG. This is fine, and you're right that it wouldn't have an affect if anything stays the same. However with more possessions, the offense get a chance to attack more, and will probably make it. If not, then their FG% may stink. FGA means more chances of points. FG% is the likely of that point, which is why comparing the eras would matter and probably will be invalid.

The FG% or better stated points per possession can go up or down with extra possessions. There is nothing inherent within the formula that would make it go up.

Game 1 (Game is stopped in the 3rd quarter because the power goes off in the stadium)

Team A defense gives up 75 points in 75 possessions at the end of 3 quarter.

DEF RATING = 100

The Game is restarted for 1/2 of the 4th quarter and the offense is in a slump
before the power goes out again

Team A defense gives up 78 points in 85 possessions

DEF RATING= 91.7

Power is back on and Kobe closes out the game on fire (15/15)

Team A defense gives up 108 points in 100 possessions

DEF RATING= 108

It wasn't more possessions that changed the rating. It was initially great defense in the 4th quarter as the Lakers went cold and weak defense at the end of of the game when Kobe lit them up.

 03-30-2011, 10:51 AM #21 necya Local High School Star     Join Date: Jun 2010 Posts: 1,430 Re: Defensive rating (DRtg) How you calculate it and use it the way you are talking about basketball is a shame. hopefully, just trolling on a forum can bring some fun.
03-30-2011, 11:18 AM   #22
Christofire
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Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by Micku Exactly. And if a team has more possessions, it usually leads to more scoring across the board. At least more chances of scoring.

the 2000s still have the better d ratings though...I'm missing the point of what you're getting at.

Please clarify what you're trying to say because i think it's quite clear that PACE doesnt change D ratings because it's affected by point per possession

03-30-2011, 11:21 AM   #23
Yao Ming's Foot
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Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by necya the way you are talking about basketball is a shame. hopefully, just trolling on a forum can bring some fun.

Teaching math to Jordan fanboys is a tough job, but somebody has to do it.

03-30-2011, 11:43 AM   #24
chazzy
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Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by Micku However with more possessions, the offense get a chance to attack more, and will probably make it. If not, then their FG% may stink. FGA means more chances of points. FG% is the likely of that point, which is why comparing the eras would matter and probably will be invalid.
You could also argue that with increased volume comes lowered efficiency.

03-30-2011, 01:02 PM   #25
necya
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Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by Yao Ming's Foot Teaching math to Jordan fanboys is a tough job, but somebody has to do it.

who are those jordan fanboys?? and why it's you? because we always sacrifice the ones who don't think first?

see, how you look stupid with your kobe agenda. your only goal is to continue to believe that kobe played better defense. lie to yourself if you want, but don't write all those shitty post.

03-30-2011, 04:16 PM   #26
Micku
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Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by Yao Ming's Foot The FG% or better stated points per possession can go up or down with extra possessions. There is nothing inherent within the formula that would make it go up. Game 1 (Game is stopped in the 3rd quarter because the power goes off in the stadium) Team A defense gives up 75 points in 75 possessions at the end of 3 quarter. DEF RATING = 100 The Game is restarted for 1/2 of the 4th quarter and the offense is in a slump before the power goes out again Team A defense gives up 78 points in 85 possessions DEF RATING= 91.7 Power is back on and Kobe closes out the game on fire (15/15) Team A defense gives up 108 points in 100 possessions DEF RATING= 108 It wasn't more possessions that changed the rating. It was initially great defense in the 4th quarter as the Lakers went cold and weak defense at the end of of the game when Kobe lit them up.

You're right in your calculations, but the number of possessions also gives indication to the pacing of the game. This will control the tempo of the game and makes it harder to stop. If the possessions were higher, lets say the average 80s possessions as you see on the chart like:

200 possessions.

In comparison of the early 00s:

180s possessions

It gives the chances every NBA team the chances to attack more, which usually lead to more total points. NBA history has shown this throughout history, as you can almost each decade the total points slightly went up or down in comparison to the number of possessions. Because of the number of FGA goes up, usually it means you are also scoring more. Plus with the more FTAs, it also gives more chances of points.

I think that your calculations is correct only if you assume that the offensive is either strictly decent or bad. But it depends on the situation and circumstances:

Quote:
 Let’s compare two hypothetical teams: Team A and Team B. Team A prefers to set up their offense and work the ball around, patiently searching for a good shot. Team B runs up the floor and takes the first open shot available. According to the above data, Team B should score more efficiently than Team A. At first glance, this does not seem logical. Patience is a virtue, after all, and haste normally makes waste. But when you think carefully, Team A—the slow, cautious offense—is actually playing a much riskier game than Team B. For Team A, working the ball around may sometimes result in an open shot; but it might also result in a turnover. With every pass they make and with every second that they spend on offense, Team A’s chance of committing a turnover increases.

The level of slow pacing offense, fewer possessions may also make it easier to defend in comparison to the high level offense, with faster pacing. This will also affects the defensive rating since usually more FGA=chances of more points. This will make the defensive rating go down.

- http://www.82games.com/levbot.htm

In era with very high possessions and high pacing like the 80s, with them only taking mid-range to close shots, usually will lead to more points because it is more difficult to guard it seems. This shows the era difference between each between now and back then. It's also a case that each year with different number of possessions will vary not only the offensive rating, but the defensive rating. It's also a case why it could be invalid when you compare it different seasons, but the of the level of the pacing.

Quote:
 Originally Posted by chazzy You could also argue that with increased volume comes lowered efficiency.

You probably could, but it's never been like that with the teams of the NBA. Usually whoever has the most possessions, controls the pacing of the game. And usually their offense is very high, which leads to higher scoring.

Last edited by Micku : 03-30-2011 at 04:22 PM.

03-30-2011, 05:46 PM   #27
Micku
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Re: Defensive rating (DRtg) How you calculate it and use it

Plus look at this quote:

Quote:
 “I don’t think this kind of analysis makes sense. What you’re calling higher average team productivity probably just reflects factors like a faster leaguewide pace, higher scoring per possession, and maybe trends in some specific statistics. A faster pace allows players to accumulate more statistics, so it’ll lead to higher pre-adjustment WP. With many statistics the two teams’ change in WP cancels out (e.g., a steal for one team is a turnover for the other, a defensive rebound requires a missed shot), but not with scoring, so more offense will increase pre-adjustment WP. The 1990s saw a drop in both pace and points per possession, so that explains the drop in “basketball quality.””

- http://arturogalletti.wordpress.com/...ting-for-pace/

This is what I'm saying. Usually when teams have more possession, they have the most points because the game is more face pace and it may lead to easier points. This is evidence if you look at the ppg and point total in every single decade.

As the possessions went down, so did the point totals. You can also calculate it yourself with the teams now and compare it to the 80s, 70s, and whatever. You'll notice that the average teams has more possessions, which leads to more points because they have more opportunities to score.

This is way comparing defensive rating to the any other season does not compute well because it is inflated. It is best to use defensive rating when the pacing is similar.

03-30-2011, 05:54 PM   #28
chazzy
3-time NBA All-Star

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Location: LA
Posts: 10,268
Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by Micku You probably could, but it's never been like that with the teams of the NBA. Usually whoever has the most possessions, controls the pacing of the game. And usually their offense is very high, which leads to higher scoring.
Of course the scoring would be higher, as more possessions are being used.. it's like a player who normally takes 15 shots ups his attempts to 20+; you would expect the scoring to go up but the efficiency to take a hit. Minnesota has the fastest pace in the league right now but they're near the bottom of the league in offensive efficiency. Higher pace can lead to quicker fastbreak opportunities and easier baskets if that's what you mean.

Last edited by chazzy : 03-30-2011 at 05:59 PM.

03-30-2011, 06:02 PM   #29
tpols

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Posts: 20,940
Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by Micku Yes it does. More possessions means more chances of scoring and more chances of defending. Especially if you take into account of pacing and how good the offense is. What you are doing is showing a point per possession, which is fine. But you are demonstrating a game which everybody shoots decent % in FG. This is fine, and you're right that it wouldn't have an affect if anything stays the same. However with more possessions, the offense get a chance to attack more, and will probably make it. If not, then their FG% may stink. FGA means more chances of points. FG% is the likely of that point, which is why comparing the eras would matter and probably will be invalid.
Wait.. you're saying that the more possesions a team uses and the faster they play, the better chance they have at scoring? How does that make sense? A team can be fastpaced and suck and they can be slow paced and suck. It doesn't matter. How efficient a team is has nothing to do with how many shots they take, but how good they are relative to how good the team they're playing is defensively.

Defensive rating is a completely normalized formula that computes everything relatively.. meaning it can be compared across slow and fast paced teams.

03-30-2011, 06:07 PM   #30
Yao Ming's Foot
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Re: Defensive rating (DRtg) How you calculate it and use it

Quote:
 Originally Posted by Micku You're right in your calculations, but the number of possessions also gives indication to the pacing of the game. This will control the tempo of the game and makes it harder to stop. If the possessions were higher, lets say the average 80s possessions as you see on the chart like: 200 possessions. In comparison of the early 00s: 180s possessions It gives the chances every NBA team the chances to attack more, which usually lead to more total points. NBA history has shown this throughout history, as you can almost each decade the total points slightly went up or down in comparison to the number of possessions. Because of the number of FGA goes up, usually it means you are also scoring more. Plus with the more FTAs, it also gives more chances of points. I think that your calculations is correct only if you assume that the offensive is either strictly decent or bad. But it depends on the situation and circumstances: The level of slow pacing offense, fewer possessions may also make it easier to defend in comparison to the high level offense, with faster pacing. This will also affects the defensive rating since usually more FGA=chances of more points. This will make the defensive rating go down. - http://www.82games.com/levbot.htm In era with very high possessions and high pacing like the 80s, with them only taking mid-range to close shots, usually will lead to more points because it is more difficult to guard it seems. This shows the era difference between each between now and back then. It's also a case that each year with different number of possessions will vary not only the offensive rating, but the defensive rating. It's also a case why it could be invalid when you compare it different seasons, but the of the level of the pacing. You probably could, but it's never been like that with the teams of the NBA. Usually whoever has the most possessions, controls the pacing of the game. And usually their offense is very high, which leads to higher scoring.

Thats a lot of words to say more possessions = more scoring. Nobody denies that. That was never in question. You have just successfully established that Jordan's raw scoring totals are inflated because he played in an era of fast pace. Now what?

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