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Swashcuff
08-28-2010, 09:40 AM
http://www.basketball-reference.com/blog/?p=7276


Here are some quick logistic regressions I ran between offensive/defensive efficiency (as measured by my 1951-2010 estimation equation) and whether or not a team won a championship...

The first regression is between regular-season offensive/defensive rating (relative to the league average) and championships won since 1951, the first year for which I can estimate possessions. The logistic equation to predict championship probability from RS efficiencies was:

p(C) ~ 1 / (1 + EXP(4.7267572 - (0.3988116 * Offense) + (0.612137 * Defense)))

From this equation, we would expect an average team during the Regular Season (0.0 on offense & defense) to have a 0.9% chance of winning an NBA title. If you increase offense to the following levels while keeping defense average, you see this pattern:


Offense Defense p(C)
0.0 0.0 0.9%
1.0 0.0 1.3%
2.0 0.0 1.9%
3.0 0.0 2.8%
4.0 0.0 4.2%
5.0 0.0 6.1%
6.0 0.0 8.8%
7.0 0.0 12.6%
8.0 0.0 17.7%
9.0 0.0 24.3%
10.0 0.0 32.3%
Conversely, if you make the defense better while keeping the offense average, here are the expected championship probabilities:

Offense Defense p(C)
0.0 0.0 0.9%
0.0 -1.0 1.6%
0.0 -2.0 2.9%
0.0 -3.0 5.3%
0.0 -4.0 9.3%
0.0 -5.0 15.9%
0.0 -6.0 25.8%
0.0 -7.0 39.1%
0.0 -8.0 54.2%
0.0 -9.0 68.6%
0.0 -10.0 80.1%
As you can see, this result seems to bear out the old adage that "Defense Wins Championships"; for instance, to have the exact same title odds as a team with an average offense and a defense that was 5.0 pts/100 poss better than average, an average defensive team would have to score 7.7 more pts/100 poss than average!

However, we're taking into account all of NBA history here (well, except for 1950), and in case you forgot, there was this ridiculous defensive dynasty in the late '50s & 1960s that probably skews the findings heavily toward defense... Check out the Celtics' yearly offensive/defensive efficiency splits relative to the league average during their 11 championship seasons:

Year Team W L Champs Off Def
1957 Boston Celtics 44 28 1 0.27 -4.26
1958 Boston Celtics 49 23 0 0.35 -4.10
1959 Boston Celtics 52 20 1 0.69 -4.37
1960 Boston Celtics 59 16 1 1.41 -4.77
1961 Boston Celtics 57 22 1 -2.14 -6.37
1962 Boston Celtics 60 20 1 0.31 -6.85
1963 Boston Celtics 58 22 1 -1.75 -7.42
1964 Boston Celtics 59 21 1 -2.90 -9.27
1965 Boston Celtics 62 18 1 -1.11 -7.98
1966 Boston Celtics 54 26 1 -1.54 -5.57
1967 Boston Celtics 60 21 0 2.49 -4.14
1968 Boston Celtics 54 28 1 -0.48 -3.87
1969 Boston Celtics 48 34 1 -0.74 -5.52
(Note: Remember, positive is good for offenses, but negative is good for defenses.)

Boston's dominance during that stretch could possibly be inflating our sense of whether defensive teams are more likely to win because: A) Their defense was so historically outstanding in the Bill Russell era; and B) Their offense was so mediocre (they were below-average in 7 of the 13 years listed above!). To avoid the possibility of this skewing our sample, let's re-run the regression using only results since the 1976 ABA-NBA merger (and using the traditional possessions formula rather than the historical estimation):

p(C) ~ 1 / (1 + EXP(5.5573404 - (0.5306148 * Offense) + (0.6129486 * Defense)))

Once again, here are the tables for average defenses (left) and offenses (right):

Offense Defense p(C) Offense Defense p(C)
0.0 0.0 0.4% 0.0 0.0 0.4%
1.0 0.0 0.7% 0.0 -1.0 0.7%
2.0 0.0 1.1% 0.0 -2.0 1.3%
3.0 0.0 1.9% 0.0 -3.0 2.4%
4.0 0.0 3.1% 0.0 -4.0 4.3%
5.0 0.0 5.2% 0.0 -5.0 7.6%
6.0 0.0 8.5% 0.0 -6.0 13.2%
7.0 0.0 13.7% 0.0 -7.0 22.0%
8.0 0.0 21.2% 0.0 -8.0 34.2%
9.0 0.0 31.4% 0.0 -9.0 49.0%
10.0 0.0 43.8% 0.0 -10.0 63.9%
These findings still bear out the axiom of defense winning championships, but the split between offense & defense is much smaller than it had been when we included pre-merger seasons. Going back to our earlier example, to have the same p(C) as a team with an average offense and a -5.0 defense, an average defensive team would have to score only 5.8 more pts/100 poss than average if we use this equation.

However, the continued prominence of defense even when we drop the heavily D-oriented Celtics dynasty from the sample does suggest that, all things being equal, teams should prioritize excellence at that end of the court if they want to win a championship.

Its a good read.

stejay
08-28-2010, 09:58 AM
That is a good read...But I am gonna state the absolute obvious, and say you cant say one is better than the other. I'mma have to say that a combination of both, a heck of a lot of luck, and good coaching strategy wins championships. That said, the article was interesting, even though it heavily relies on the dynasty of the Celtics, which as it says in the article, was very D orientated. I think that may mess up the stats a little...

llemon
08-28-2010, 10:27 AM
Yes

stejay
08-28-2010, 10:32 AM
Yes

Aint gonna argue your point man?

llemon
08-28-2010, 10:35 AM
Aint gonna argue your point man?

No.

Was that a set-up?

stejay
08-28-2010, 10:36 AM
No.

Was that a set-up?

A set up for what man?... I was just saying, you just say "yes", and dont explain your point. Just saying man.....

save the knicks
08-28-2010, 10:37 AM
I thought whoever scores more points wins?

stejay
08-28-2010, 10:40 AM
I thought whoever scores more points wins?

Thats why I think its a mixture...They aint no point in having a **** load of blocks, rebounds and steals, if you cant knock down your jumpers. Same on the opposite side of the argument. You cant keep trading score for score, and be bad on defense, cause all it takes is 2-3 missed shots, and you looking at a 9 point defecit, if they hitting J's. So you cant have one without the other, as obvious as it sounds.

save the knicks
08-28-2010, 10:43 AM
Thats why I think its a mixture...They aint no point in having a **** load of blocks, rebounds and steals, if you cant knock down your jumpers. Same on the opposite side of the argument. You cant keep trading score for score, and be bad on defense, cause all it takes is 2-3 missed shots, and you looking at a 9 point defecit, if they hitting J's. So you cant have one without the other, as obvious as it sounds.

Yeah trying to boil it down to a single axiom seems absurd to me too. I think that coaches emphasize D because most players would rather practice offense

dhopisthename
08-28-2010, 10:44 AM
I thought whoever scores more points wins?

That's what they want you to think.

I think the reason defense wins championships is that it is easier to maintain a good defense in the playoffs then it is to maintain a good offense.

Faycem
08-28-2010, 10:44 AM
Pointless. If people say that defense wins chapionships is talking about contenders that, obviously, are great offensive teams. Their offense will be there, but the difference maker will be their defense at the end of the road. Somebody think about Celtics as an average offensive team? Come on.

stejay
08-28-2010, 10:46 AM
Plus, its very quotable, which in the sports world, always helps it seems

Avenged
08-28-2010, 10:47 AM
Defense wins championships. By just looking at the last couple of champions (Lakers, Celtics, Spurs, Pistons) all defensive minded teams.

You do need a combination of both though, only defense will not get you one considering the opposing team in the Finals also has to be a good defensive team if they've made it that far.

Swashcuff
08-28-2010, 10:49 AM
Defense DOES NOT Win Championships Great Teams do.

Avenged
08-28-2010, 10:51 AM
Defense DOES NOT Win Championships Great Teams do.

To be a great team you have to be good overall, and that includes defense.

stejay
08-28-2010, 10:51 AM
Defense wins championships. By just looking at the last couple of champions (Lakers, Celtics, Spurs, Pistons) all defensive minded teams.

You do need a combination of both though, only defense will not get you one considering the opposing team in the Finals also has to be a good defensive team if they've made it that far.

You say that, but you got offensive greats on them teams..... You got Kobe, Parker, Ginobli, Fisher, Garnett, Allen, Pierce, etc etc etc.....It is so obviously a mixture....You cant have 1 without the other.

TheDetroitBlue
08-28-2010, 10:51 AM
I believe Defense does when championships

Just look at 04 Pistons, They were not name brand players but there defense shut down opponents

stejay
08-28-2010, 10:52 AM
To be a great team you have to be good overall, and that includes defense.

Barely anyone is discounting defense...most, including myself, are saying its a mixture of both.

mynameismo
08-28-2010, 10:53 AM
Because Defense is consistent. Contesting shots, boxing out, hustle and tight defense never takes an off night.

midwestmadman
08-28-2010, 10:55 AM
Defense used to win championships, but they way the NBA is played (most notable called) today, that, unfortunately is no longer the case. The NBA has changed it rules so many times over the years that what used to be a clean defensive play is now 2 shoots the ball out of bounds and many times a suspension. Look at the 2005 NBA finals when the games were being called half way accruate Dallas was destoying Miami, once the refs decided to give Wade every call (avg about 20 FTA per game in the series and closer to 25 FTA in the last 4 games) the Heat made thier title run. The refs and David Stern are most responsible for who will be the champion season in and seaon out.

Antipod
08-28-2010, 10:59 AM
"Article: Does Defense Really Win Championships?" - No mate, teams like Golden State do xDD

save the knicks
08-28-2010, 11:01 AM
How about winning the 4 factors!????

Avenged
08-28-2010, 11:02 AM
You say that, but you got offensive greats on them teams..... You got Kobe, Parker, Ginobli, Fisher, Garnett, Allen, Pierce, etc etc etc.....It is so obviously a mixture....You cant have 1 without the other.

Yep, and that's why I said it's a combination of both. (usually)


Barely anyone is discounting defense...most, including myself, are saying its a mixture of both.

And that's what I said, again.

Swashcuff
08-28-2010, 11:09 AM
To be a great team you have to be good overall, and that includes defense.

Yes while very true.

IMO however just basing defense as the formula to win a ship may be inaccurate. YES a team has to be able to make the stops when the most matter but they also have to be able to initiate the offense effectively to be able to come out on top 4 out of 7 times.

save the knicks
08-28-2010, 11:20 AM
Yes while very true.

IMO however just basing defense as the formula to win a ship may be inaccurate. YES a team has to be able to make the stops when the most matter but they also have to be able to initiate the offense effectively to be able to come out on top 4 out of 7 times.

Bobcats come to mind

nanablvd
08-28-2010, 11:50 AM
Where can we get data like that cuz i wanna run my own regressions.

llemon
08-28-2010, 11:57 AM
I thought whoever scores more points wins?

Whoever scores less points loses

Byronicle
08-28-2010, 12:11 PM
this is a no brainer. why would you need some fancy calculation to prove that its not all in the defense. how are you suppose to win games? by putting up more points than the opposing team and getting it done

arkanian215
08-28-2010, 12:17 PM
It's a good read. I'm just wondering why they don't do a moving average instead since different eras have different styles. He did factor out the Celtics run but I think it's better if he incorporated MA's. I think he should look at playoff offensive and defensive efficiencies as well since the playoffs aren't won in the regular season. The sample size for the regular season is bigger but I think he's looking at the wrong sample here.

arkanian215
08-28-2010, 12:21 PM
Where can we get data like that cuz i wanna run my own regressions.

hm....the numbers are available on B-R. He has a formula in the link and you can just crunch the numbers in excel but those numbers should all be there.

I got confused earlier thinking that his defensive efficiency was the same as defensive rating.

ThaRegul8r
08-29-2010, 03:22 AM
Whoever scores less points loses

This. I dunno why everyone only looks at it as "You have to outscore your opponent to win." No, to win, you make sure that when the final buzzer sounds, your opponent has less points than you do. You can accomplish this through defense.

icej
08-29-2010, 03:48 AM
Defense used to win championships, but they way the NBA is played (most notable called) today, that, unfortunately is no longer the case. The NBA has changed it rules so many times over the years that what used to be a clean defensive play is now 2 shoots the ball out of bounds and many times a suspension. Look at the 2005 NBA finals when the games were being called half way accruate Dallas was destoying Miami, once the refs decided to give Wade every call (avg about 20 FTA per game in the series and closer to 25 FTA in the last 4 games) the Heat made thier title run. The refs and David Stern are most responsible for who will be the champion season in and seaon out.

^^^This is the fact.

The quote "Defense wins Championships" in today's NBA basketball is no longer DEFENSIBLE.

shep33
08-29-2010, 04:21 AM
Obviously you need a bit of both. The Celtics were a terrific defensive team this year, and because of their defense they always had a chance to win.

That being said the Lakers played ridiculous defense on the Celtics in those final 2 games. Now the point I'm making with this is that you must play excellent defense at times to win it all. So yeah you can give up a lot of points in a couple of games, but when its time to win, teams usually lockdown and get it done.

Great defense in stretches are required to win it.

King P
08-29-2010, 04:23 AM
A good defnese is the difference between giveing up 85-90 points and 95-100 points. And that is a huge difference.

Law25
08-29-2010, 04:56 AM
That is a good read...But I am gonna state the absolute obvious, and say you cant say one is better than the other. I'mma have to say that a combination of both, a heck of a lot of luck, and good coaching strategy wins championships. That said, the article was interesting, even though it heavily relies on the dynasty of the Celtics, which as it says in the article, was very D orientated. I think that may mess up the stats a little...

Agreed

Wade>You
08-29-2010, 05:03 AM
Is anyone else tired of the " I hate NBA" threads? I watched the Lakers' and Celtics' defense get away with murder last season, and these are the two best teams in the league. Defense does exist and it does win championships.

BkOriginalOne
08-29-2010, 05:13 AM
In What sport does defense not win Championships?
Golf?

brknwrst9
08-29-2010, 05:19 AM
i just want to point out that if you stop the other team from scoring every time they touch the ball you cannot lose. Yes I know that is the most unlikely thing to happen in basketball, but it is just a thought.

m26555
08-29-2010, 10:16 AM
I'll put it this way: you can win with a great defense and an average offense. However, you CANNOT win with a great offense and an average defense. So, yes; defense DOES win championships.

Raoul Duke
08-29-2010, 10:30 AM
I'll put it this way: you can win with a great defense and an average offense. However, you CANNOT win with a great offense and an average defense. So, yes; defense DOES win championships.

True dat. Thats basically why I consider defense to be slightly more important. Either that, or our methods of effectively evaluating a defense (on paper) are superior.

EaglePride615
08-29-2010, 10:48 AM
suns prove that d wins

Cap'nCrunch40
08-29-2010, 11:17 AM
Yes, defense wins championships. I mean, you could go like , say 6 for 24 and still win a championship.

Hawkeye15
08-29-2010, 01:16 PM
While I HATE the statement "Defense win championships", there is always a common theme amongst champions, and that is they have a good defensive team.

Steelers23_06
08-29-2010, 01:32 PM
name a team that just won off defense? look at the suns put up CRAZY numbers and never won anything because they lacked defense. you cant tin if you cant stop the other team. you dont have to be a defense 1st team but at the same time you cant lack defense.

Niro
08-29-2010, 01:38 PM
Because Defense is consistent. Contesting shots, boxing out, hustle and tight defense never takes an off night.

this...if you have an off night and you shoot only 40% and score only 85 points you normaly loose. great teams are still able to win the game because of great defense

Chacarron
08-29-2010, 01:45 PM
I thought whoever scores more points wins?

You can also say the team that allows fewer points scored wins.

Ovratd1up
08-29-2010, 02:11 PM
I'll say... At least two guys you can run the offense with, at least one guy you can turn to to score in pressure, at least one good/great perimeter defender, either one All-NBA interior defender or two good ones, and efficient role players will do it.


Examples of this could be:

Steve Blake
Thabo Sefolosha, Hill
Paul Pierce
Dirk Nowitzki, Haslem
Greg Oden,

Chauncey Billups
Brandon Roy, Matthews
Nicolas Batum
Kenyon Martin
Greg Oden, Camby,

Every championship team this decade,

etc.

Meaze_Gibson
08-29-2010, 02:39 PM
Because Defense is consistent. Contesting shots, boxing out, hustle and tight defense never takes an off night.

Exactly..And its these things that don't show in stats. I'mma laker hater all the way but Boston's inability to grab DEFENSIVE rebounds while Perk was out are what caused their demise. Defense is like a combined category of hustle, consistency, trust, and just hard work..It really is the key to winning a chip