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The Rules of Pacers Digest

Hello everyone,

Whether your are a long standing forum member or whether you have just registered today, it's a good idea to read and review the rules below so that you have a very good idea of what to expect when you come to Pacers Digest.

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Why do we do this? So that it's more difficult for spammers (be they human or robot) to post, and so users who are banned cannot immediately re-register and start dousing people with verbal flames.

Below are the rules of Pacers Digest. After you have read them, you will have a very good sense of where we are coming from, what we expect, what we don't want to see, and how we react to things.

Rule #1

Pacers Digest is intended to be a place to discuss basketball without having to deal with the kinds of behaviors or attitudes that distract people from sticking with the discussion of the topics at hand. These unwanted distractions can come in many forms, and admittedly it can sometimes be tricky to pin down each and every kind that can rear its ugly head, but we feel that the following examples and explanations cover at least a good portion of that ground and should at least give people a pretty good idea of the kinds of things we actively discourage:

"Anyone who __________ is a liar / a fool / an idiot / a blind homer / has their head buried in the sand / a blind hater / doesn't know basketball / doesn't watch the games"

"People with intelligence will agree with me when I say that __________"

"Only stupid people think / believe / do ___________"

"I can't wait to hear something from PosterX when he/she sees that **insert a given incident or current event that will have probably upset or disappointed PosterX here**"

"He/she is just delusional"

"This thread is stupid / worthless / embarrassing"

"I'm going to take a moment to point and / laugh at PosterX / GroupOfPeopleY who thought / believed *insert though/belief here*"

"Remember when PosterX said OldCommentY that no longer looks good? "

In general, if a comment goes from purely on topic to something 'ad hominem' (personal jabs, personal shots, attacks, flames, however you want to call it, towards a person, or a group of people, or a given city/state/country of people), those are most likely going to be found intolerable.

We also dissuade passive aggressive behavior. This can be various things, but common examples include statements that are basically meant to imply someone is either stupid or otherwise incapable of holding a rational conversation. This can include (but is not limited to) laughing at someone's conclusions rather than offering an honest rebuttal, asking people what game they were watching, or another common problem is Poster X will say "that player isn't that bad" and then Poster Y will say something akin to "LOL you think that player is good". We're not going to tolerate those kinds of comments out of respect for the community at large and for the sake of trying to just have an honest conversation.

Now, does the above cover absolutely every single kind of distraction that is unwanted? Probably not, but you should by now have a good idea of the general types of things we will be discouraging. The above examples are meant to give you a good feel for / idea of what we're looking for. If something new or different than the above happens to come along and results in the same problem (that being, any other attitude or behavior that ultimately distracts from actually just discussing the topic at hand, or that is otherwise disrespectful to other posters), we can and we will take action to curb this as well, so please don't take this to mean that if you managed to technically avoid saying something exactly like one of the above examples that you are then somehow off the hook.

That all having been said, our goal is to do so in a generally kind and respectful way, and that doesn't mean the moment we see something we don't like that somebody is going to be suspended or banned, either. It just means that at the very least we will probably say something about it, quite possibly snipping out the distracting parts of the post in question while leaving alone the parts that are actually just discussing the topics, and in the event of a repeating or excessive problem, then we will start issuing infractions to try to further discourage further repeat problems, and if it just never seems to improve, then finally suspensions or bans will come into play. We would prefer it never went that far, and most of the time for most of our posters, it won't ever have to.

A slip up every once and a while is pretty normal, but, again, when it becomes repetitive or excessive, something will be done. Something occasional is probably going to be let go (within reason), but when it starts to become habitual or otherwise a pattern, odds are very good that we will step in.

There's always a small minority that like to push people's buttons and/or test their own boundaries with regards to the administrators, and in the case of someone acting like that, please be aware that this is not a court of law, but a private website run by people who are simply trying to do the right thing as they see it. If we feel that you are a special case that needs to be dealt with in an exceptional way because your behavior isn't explicitly mirroring one of our above examples of what we generally discourage, we can and we will take atypical action to prevent this from continuing if you are not cooperative with us.

Also please be aware that you will not be given a pass simply by claiming that you were 'only joking,' because quite honestly, when someone really is just joking, for one thing most people tend to pick up on the joke, including the person or group that is the target of the joke, and for another thing, in the event where an honest joke gets taken seriously and it upsets or angers someone, the person who is truly 'only joking' will quite commonly go out of his / her way to apologize and will try to mend fences. People who are dishonest about their statements being 'jokes' do not do so, and in turn that becomes a clear sign of what is really going on. It's nothing new.

In any case, quite frankly, the overall quality and health of the entire forum's community is more important than any one troublesome user will ever be, regardless of exactly how a problem is exhibiting itself, and if it comes down to us having to make a choice between you versus the greater health and happiness of the entire community, the community of this forum will win every time.

Lastly, there are also some posters, who are generally great contributors and do not otherwise cause any problems, who sometimes feel it's their place to provoke or to otherwise 'mess with' that small minority of people described in the last paragraph, and while we possibly might understand why you might feel you WANT to do something like that, the truth is we can't actually tolerate that kind of behavior from you any more than we can tolerate the behavior from them. So if we feel that you are trying to provoke those other posters into doing or saying something that will get themselves into trouble, then we will start to view you as a problem as well, because of the same reason as before: The overall health of the forum comes first, and trying to stir the pot with someone like that doesn't help, it just makes it worse. Some will simply disagree with this philosophy, but if so, then so be it because ultimately we have to do what we think is best so long as it's up to us.

If you see a problem that we haven't addressed, the best and most appropriate course for a forum member to take here is to look over to the left of the post in question. See underneath that poster's name, avatar, and other info, down where there's a little triangle with an exclamation point (!) in it? Click that. That allows you to report the post to the admins so we can definitely notice it and give it a look to see what we feel we should do about it. Beyond that, obviously it's human nature sometimes to want to speak up to the poster in question who has bothered you, but we would ask that you try to refrain from doing so because quite often what happens is two or more posters all start going back and forth about the original offending post, and suddenly the entire thread is off topic or otherwise derailed. So while the urge to police it yourself is understandable, it's best to just report it to us and let us handle it. Thank you!

All of the above is going to be subject to a case by case basis, but generally and broadly speaking, this should give everyone a pretty good idea of how things will typically / most often be handled.

Rule #2

If the actions of an administrator inspire you to make a comment, criticism, or express a concern about it, there is a wrong place and a couple of right places to do so.

The wrong place is to do so in the original thread in which the administrator took action. For example, if a post gets an infraction, or a post gets deleted, or a comment within a larger post gets clipped out, in a thread discussing Paul George, the wrong thing to do is to distract from the discussion of Paul George by adding your off topic thoughts on what the administrator did.

The right places to do so are:

A) Start a thread about the specific incident you want to talk about on the Feedback board. This way you are able to express yourself in an area that doesn't throw another thread off topic, and this way others can add their two cents as well if they wish, and additionally if there's something that needs to be said by the administrators, that is where they will respond to it.

B) Send a private message to the administrators, and they can respond to you that way.

If this is done the wrong way, those comments will be deleted, and if it's a repeating problem then it may also receive an infraction as well.

Rule #3

If a poster is bothering you, and an administrator has not or will not deal with that poster to the extent that you would prefer, you have a powerful tool at your disposal, one that has recently been upgraded and is now better than ever: The ability to ignore a user.

When you ignore a user, you will unfortunately still see some hints of their existence (nothing we can do about that), however, it does the following key things:

A) Any post they make will be completely invisible as you scroll through a thread.

B) The new addition to this feature: If someone QUOTES a user you are ignoring, you do not have to read who it was, or what that poster said, unless you go out of your way to click on a link to find out who it is and what they said.

To utilize this feature, from any page on Pacers Digest, scroll to the top of the page, look to the top right where it says 'Settings' and click that. From the settings page, look to the left side of the page where it says 'My Settings', and look down from there until you see 'Edit Ignore List' and click that. From here, it will say 'Add a Member to Your List...' Beneath that, click in the text box to the right of 'User Name', type in or copy & paste the username of the poster you are ignoring, and once their name is in the box, look over to the far right and click the 'Okay' button. All done!

Rule #4

Regarding infractions, currently they carry a value of one point each, and that point will expire in 31 days. If at any point a poster is carrying three points at the same time, that poster will be suspended until the oldest of the three points expires.

Rule #5

When you share or paste content or articles from another website, you must include the URL/link back to where you found it, who wrote it, and what website it's from. Said content will be removed if this doesn't happen.

An example:

If I copy and paste an article from the Indianapolis Star website, I would post something like this:

http://www.linktothearticlegoeshere.com/article
Title of the Article
Author's Name
Indianapolis Star

Rule #6

We cannot tolerate illegal videos on Pacers Digest. This means do not share any links to them, do not mention any websites that host them or link to them, do not describe how to find them in any way, and do not ask about them. Posts doing anything of the sort will be removed, the offenders will be contacted privately, and if the problem becomes habitual, you will be suspended, and if it still persists, you will probably be banned.

The legal means of watching or listening to NBA games are NBA League Pass Broadband (for US, or for International; both cost money) and NBA Audio League Pass (which is free). Look for them on NBA.com.

Rule #7

Provocative statements in a signature, or as an avatar, or as the 'tagline' beneath a poster's username (where it says 'Member' or 'Administrator' by default, if it is not altered) are an unwanted distraction that will more than likely be removed on sight. There can be shades of gray to this, but in general this could be something political or religious that is likely going to provoke or upset people, or otherwise something that is mean-spirited at the expense of a poster, a group of people, or a population.

It may or may not go without saying, but this goes for threads and posts as well, particularly when it's not made on the off-topic board (Market Square).

We do make exceptions if we feel the content is both innocuous and unlikely to cause social problems on the forum (such as wishing someone a Merry Christmas or a Happy Easter), and we also also make exceptions if such topics come up with regards to a sports figure (such as the Lance Stephenson situation bringing up discussions of domestic abuse and the law, or when Jason Collins came out as gay and how that lead to some discussion about gay rights).

However, once the discussion seems to be more/mostly about the political issues instead of the sports figure or his specific situation, the thread is usually closed.

Rule #8

We prefer self-restraint and/or modesty when making jokes or off topic comments in a sports discussion thread. They can be fun, but sometimes they derail or distract from a topic, and we don't want to see that happen. If we feel it is a problem, we will either delete or move those posts from the thread.

Rule #9

Generally speaking, we try to be a "PG-13" rated board, and we don't want to see sexual content or similarly suggestive content. Vulgarity is a more muddled issue, though again we prefer things to lean more towards "PG-13" than "R". If we feel things have gone too far, we will step in.

Rule #10

We like small signatures, not big signatures. The bigger the signature, the more likely it is an annoying or distracting signature.

Rule #11

Do not advertise anything without talking about it with the administrators first. This includes advertising with your signature, with your avatar, through private messaging, and/or by making a thread or post.
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Plus-Minus explanation please

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  • Plus-Minus explanation please

    I searched for the answer but couldn't find one that didn't remind me of some science class in high school. Would someone please explain to me what the Plus-Minus is all about? I see it on the Pacers website under their "team" tab, and I see it a lot in the after game analysis, but I have no idea what it means.

    Thank you!

  • #2
    Re: Plus-Minus explanation please

    Heres a good reading for you:
    2005-2006 Adjusted Plus-Minus Ratings
    By David Lewin
    For a good explanation of the adjusted plus-minus ratings that follow, click here:

    http://www.washtimes.com/sports/2004...1657-1462r.htm (Winston/Sagarin)
    Or here: http://www.82games.com/comm30.htm (Dan Rosenbaum)
    If you would like my mediocre explanation, keep reading.
    Note: The three guys responsible for the numbers in the two articles above all work for NBA teams now, so their numbers are no longer publicly available. Below I apply their method to the 2005-2006 NBA season.

    Most of the time, when people talk about basketball statistics the conversation comes back to their limits. Basketball statistics, like points, rebounds, and assists tell you something about what happened, but many people think they miss the real reasons why teams win and lose. Box score statistics are said to miss the intangibles, the guys who are winners but might not fill up the stat sheet.

    One simple, but until recently little used, way of evaluating players is seeing whether a team does better or worse with a player on the court. This captures a player’s total effect on the team, not just those things that show up in a box score. This approach, pioneered here at 82games.com, is known as plus-minus rating, or on court-off court rating. On court-off court numbers are useful, but they depend heavily on who else is on the floor. When you adjust these numbers to take into account the other players on the court it is known as an adjusted plus-minus statistic.

    I’ll use an example to illustrate what an adjusted plus-minus statistic is exactly. Lets say you’re at the gym and you’re playing some two on two with your friends. The first game its you and your buddy Ted against two other guys. You win this game by 4. The next game, it’s you and your other buddy Jim against the same two guys. You lose this game by 2. Finally, there is third game, but this time you sit out and Jim and Ted play. They win by 1. From these games you can tell that you are three points per game better than Jim, and that Ted is three points per game better than you, six better than Jim. These are basically adjusted plus-minus statistics.

    Now, you wouldn’t generalize from just these three games. Maybe Jim’s jumpshot just wasn’t falling that day. Maybe you and Jim are similar players who don’t play well together but work well with a guy like Ted. It’s difficult to say for sure from just three observations involving three players. However, for an NBA season we don’t have just three pick-up games, we have 40,000 observations involving 700 players.

    Every period between substitutions is one small game. Who wins and by how much is the result of the players who were on the court. By comparing these different periods using a mathematical technique called regression we can get a good idea of how the team does with a given player in the game. If a player causes his team to score more than the other team when he is on the court we call him a good player. If he lets the other team score more than his team then he is a bad player. Pretty simple.

    Adjusted plus-minus statistics take into account everything a player does on the court that affects the game. This includes things that many other statistics measure, like scoring a basket, but it also includes things like setting a good screen, or playing good man-to-man defense which are difficult to track. Another set of effects that are often missed but are accounted for here are inter-player effects. For instance, if having a three-point shooter on the floor opens up court for other players and causes them to play better when one is in the game, then the three-point shooter will get credit for this even if he doesn’t take any shots.

    Adjusted plus-minus statistics are descriptive statistics, just like points per game, field goal percentage, rebounds per game, etc. Points per game describes how many points, on average a player scores in a game. Field goal percentage describes the ratio of a player’s shots made to his shots attempted. Adjusted plus-minus describes the average performance of the team with a given player in the game, taking into account the other nine players on the court.

    Like points per game, or field goal percentage, adjusted plus-minus doesn’t mean anything without context. For instance looking at the Los Angeles Lakers’ statistics from 2005-2006 without context it would be reasonable to conclude that Slava Medvedenko is a better shooter than Kobe Bryant because he had a better shooting percentage (.500 to .450).

    Should the Lakers’ focus their offense around Slava instead of Kobe? Probably not. Does this mean that field goal percentage is useless? No.

    There are a number of reasons why Kobe’s shooting percentage was lower than Slava’s. For starters, Slava attempted only two shots over the course of the entire season while Kobe attempted 2173. This means that Slava’s percentage is very likely to be due to luck, while Kobe’s is probably a good description of his actual ability. Another issue is that Kobe had a very different role than Slava: he took more shots, he took shots from different places, and he played a different position. Once you take this context into account, field goal percentage can provide very valuable information about shooting ability, but without it, it can look ridiculous.

    The same logic needs to be applied to adjusted plus-minus statistics. Because adjusted plus-minus statistics depend on comparing how the changing of one player affects the performance of the team while holding everything else constant, sample size is important. Not just how many minutes a player played, but how broad a diversity of teammates did he play with. For teams with rigid rotations, like the Detroit Pistons, this can be problematic (as you will see).

    Despite these caveats, in general, adjusted plus-minus statistics give a good picture of which players help their team win, and that’s pretty much the whole point of the game, isn’t it?

    2005-2006 Adjusted Plus-Minus Ratings
    Adjusted plus-minus is given in points per 100 possessions relative to an average player. The first table is the 25 best players in 2005-2006, the second table is the 10 worst. Must play at least 500 minutes to qualify.

    Top 25 Players
    Player Team Min. Rating
    Rasheed Wallace Pistons 70% 20.20
    LeBron James Cavaliers 85% 19.59
    Ben Wallace Pistons 73% 17.92
    Kobe Bryant Lakers 82% 14.34
    Andrei Kirilenko Jazz 66% 13.83
    Yao Ming Rockets 49% 13.63
    Ron Artest Kings 56% 11.83
    Alonzo Mourning Heat 33% 11.78
    Andre Iguodala 76ers 78% 11.60
    Brad Miller Kings 73% 11.07
    Jason Richardson Warriors 72% 10.53
    Dirk Nowitzki Mavericks 78% 10.52
    Chris Paul Hornets 71% 10.22
    Manu Ginobili Spurs 46% 10.01
    Ray Allen Supersonics 76% 9.84
    Steve Nash Suns 70% 9.63
    Dwyane Wade Heat 73% 9.57
    Kirk Snyder Hornets 33% 9.50
    Brent Barry Spurs 32% 9.43
    Jake Tsakalidis Grizzlies 18% 9.28
    Antonio McDyess Pistons 44% 9.24
    Antawn Jamison Wizards 83% 9.24
    Charles Hayes Rockets 13% 9.18
    Shaquille O'Neal Heat 45% 9.12
    Boris Diaw Suns 72% 8.86


    Bottom 15
    Player Team Min. Rating
    Desmond Mason Hornets 53% -9.62
    Chris Mihm Lakers 39% -9.66
    Alan Henderson Cavaliers 13% -10.16
    Pape Sow Raptors 15% -10.84
    Maurice Evans Pistons 29% -10.85
    Antonio Davis Knicks 19% -11.11
    Jason Kapono Heat 17% -11.52
    Jiri Welsch Bucks 22% -11.65
    Juwan Howard Rockets 64% -11.77
    Dahntay Jones Grizzlies 24% -11.85
    Primoz Brezec Bobcats 54% -11.91
    Drew Gooden Cavaliers 55% -12.52
    Michael Olowokandi Timberwolves 23% -13.39
    Carlos Delfino Pistons 18% -15.29
    Richard Hamilton Pistons 71% -17.90


    So, who was the best player in the NBA last year? Well, among those with greater than 500 minutes in 05-06, Rasheed Wallace had the highest per possession influence. However, taking a closer look at the data, you can see that there is something weird going on with the Detroit Pistons, which I will discuss later. For now lets leave the Pistons out, which means LeBron James was the best player in the NBA last year by a wide margin. Rounding out the top five, Pistons excluded, are Kobe Bryant, Andrei Kirilenko, Yao Ming, and Ron Artest.

    The numbers seem to generally align with conventional wisdom, although there are some surprises. The biggest surprise to me, actually, was how much better than everyone else LeBron really is. At nearly 20 points per 100 possessions better than an average player, LeBron is head and shoulders above the rest of the (non-Piston) league. He should have run away with the MVP. Steve Nash was a good player last year, no doubt, but the difference between LeBron and Steve Nash was bigger than the difference between Steve Nash and Sasha Vujacic.

    - Kirilenko and Ming have clearly established themselves as elite players in the league. Unfortunately Kirilenko and Yao’s sidekick, Tracy McGrady, have the same problem, they can’t stay healthy.
    - Artest didn’t let all the drama surrounding his trade demand effect his play. Adjusted plus-minus captures the one-on-one defense of players like Artest, Quinton Ross, and Shane Battier, an area that most statistical measures usually. When you combine Artest’s offensive prowess with his elite defensive ability you get a top ten player in the league, albeit a crazy one.
    - Chris Paul produced a remarkable rookie season. You probably already knew this, but some might have wondered if his impact was really as strong as his box score stats indicated given that the team played better with him off the court according to raw plus-minus. However, this is a case where adjusting for who he had to play with and against makes all the difference. With the adjustments Paul was the 13th best player in the NBA last year (>500 min), slightly ahead of Steve Nash as the best point guard. Here’s a list of notable rookies:

    Notable Rookies
    Player Team Min. Rating
    Chris Paul Hornets 71% 10.22
    Charles Hayes Rockets 13% 9.18
    Nate Robinson Knicks 39% 7.09
    Monta Ellis Warriors 22% 6.00
    Luther Head Rockets 58% 4.97
    Marvin Williams Hawks 49% 4.74
    Raymond Felton Bobcats 61% 4.35
    Andrew Bogut Bucks 59% 4.09
    Charlie Villanueva Raptors 59% 2.56
    Sarunas Jasikevicius Pacers 39% 1.45
    Ryan Gomes Celtics 35% 1.31
    Channing Frye Knicks 40% -1.40
    Jose Calderon Raptors 37% -1.71
    Danny Granger Pacers 44% -3.14
    Francisco Garcia Kings 33% -3.44
    Salim Stoudamire Hawks 31% -3.69
    Joey Graham Raptors 40% -5.24
    Deron Williams Jazz 58% -5.80
    Johan Petro Supersonics 32% -6.34
    Jarrett Jack Trail Blazers 40% -9.41


    The Allen Iverson Trade
    The biggest story in basketball lately is Allen Iverson’s move to Denver. There has been a lot of speculation as to whether the Nuggets are now a title contender, or if this trade even makes them better. Iverson is clearly a great scorer, but he tends to use a huge number of possessions inefficiently, and doesn’t play much defense. I was very surprised to see John Hollinger gloss over these facts in his recent review of the trade, but clearly he buys into the conventional wisdom that although Iverson is flawed his scoring ability is enough to make his teams better.

    Reality tells a bit of a different story. In 2005-2006 Iverson made his team 7.38 points per 100 possessions better with him on the court (as opposed to replacing him with an average player). This is good, 42nd in the league, but not as good as Iverson’s reputation would lead you to expect. Andre Miller closely followed Iverson, ranking 52nd with a value of 6.62. In 2004-2005 (full report on that data coming next week) Iverson actually had an impact of -4.41 compared to an average player. Miller was more consistent year to year, with a value of 5.62. This suggests that if both players play as they have in the past then the Nuggets will be at best as good as they were before the trade.

    It’s important to remember that all statistics tell us what a player did, not what he will do. Knowing Iverson averaged 33 points per game last year with the Sixers last year does not mean he’ll average 33 with the Nuggets this year. He might, but he might not. Same goes for adjusted plus-minus. While Iverson was only a slightly above average player over the last two years (which doesn’t mean he didn’t have any value, he did, he played a lot of minutes that otherwise would have gone to players worse than average), it’s difficult to say for sure how a move to the Nuggets will affect his play. It is certainly possible that Iverson will change his game and cause the Nuggets to be a better team. All I can say is that past returns indicate Iverson is unlikely to be much of an upgrade over Andre Miller.

    The Detroit Pistons, and Other Possible Sources of Error


    Detroit Pistons
    Player Team Min. Rating
    Rasheed Wallace Pistons 70% 20.20
    Ben Wallace Pistons 73% 17.92
    Antonio McDyess Pistons 44% 9.24
    Lindsey Hunter Pistons 9% 6.52
    Chauncey Billups Pistons 74% 3.72
    Carlos Arroyo Pistons 15% 3.33
    Tayshaun Prince Pistons 73% -3.25
    Maurice Evans Pistons 29% -10.85
    Carlos Delfino Pistons 18% -15.29
    Richard Hamilton Pistons 71% -17.90


    One look at the values for the Detroit Pistons starting five tells you something is up. The Wallaces rate at the very top of the league, Chauncey Billups is above average, Tayshaun Prince is below average, and Richard Hamilton is among the worst in the league. This is not what you would have expected. Also surprising is Antonio McDyess’ rating as the 18th best player in the league.

    In 2005-2006 the Pistons were a historically unique team. According to 82games.com they played their starting five together for 1674 minutes. The New Jersey Nets were the only other team in the league to have one lineup play at least 1000 minutes together. Most teams didn’t even have a 5-man unit with 500 minutes. In addition, the Pistons played another 314 minutes with the same lineup only McDyess subbed in for one of the Wallaces. The Detroit starting five’s individual minutes played range from 2776 to 2922. In order to separate the value of players who play together you have to look at the time in which they did not share the court and in this case, that is a very small sample.

    Take Ben Wallace and Richard Hamilton for instance. They shared the court for about 85% of their minutes. During these shared minutes the Pistons were successful. However, Wallace has on of the highest ratings in the league while Hamilton has one of the lowest. This is because the system gives Ben Wallace most of the credit for what those two accomplished while they were on the court together. Why does it do this? Because during the short period when Hamilton was in the game and Ben Wallace wasn’t the Pistons did worse than usual, and during the short period that Ben was in the game and Hamilton wasn’t the Pistons played well. This is a reasonable inference, but when it’s based on only two or three hundred minutes then it is not reliable. Luckily, the Pistons are the only team for whom this is a major issue because their substitution patterns were so dramatically different than any other team in the league.

    A reasonable way to correct for this would be to just assign each member of Pistons starting five equal credit for the time the unit spent on the floor together. Doing this results in the following values for the Pistons starting five: R. Wallace 10.49, B. Wallace 9.9, Billups 3.94, Prince 1.00, Hamilton -4.86. So Hamilton is still negative, even when given one fifth of the credit for Detroit’s dominant starting five. These values seems more reasonable to me, but in terms of sheer descriptive accuracy the regressed values are the best.

    This problem can occur on a smaller level when two players play almost all of their minutes together. One example of this is Gilbert Arenas and Antwan Jamison of the Wizards.


    Jamison-Arenas
    Player Team Min. Rating
    Antawn Jamison Wizards 83% 9.24
    Gilbert Arenas Wizards 85% 2.58


    Arenas was on the floor for 89% of Jamison’s minutes. The Wizards outscored their opponents by 240 points (in 2920 minutes) when they were both on the floor. When just Jamison was on the floor they outscored their opponents by 4 (363 minutes). When just Arenas was on the floor the Wizards were outscored by 35 (460 minutes).

    The inference the system makes, that Jamison was the main reason why the Wizards were good when both players were on the floor, is reasonable, but based on a small sample size. So, as I did with the Pistons’ starting five I’ll give Arenas and Jamison equal credit for what happened when they shared the court. Doing this gives Jamison a value of 6.20 and Arenas a value of 5.38. Point being even in cases where there is heavy overlap the regression distributes credit in the most accurate way, and any difference from what might be expected is due to differences between expectations and reality.

    Notes: Dan Rosenbaum chose to add a clutch/garbage time adjustment to his system that weighted different periods of the game differently. I chose not to do this because, while Dan’s weights were probably reasonable, they were subjective and I want these numbers to be purely objective and descriptive. I believe Sagarin-Winston model uses expected win probabilities to determine how much each player changed the team’s chance of winning. I am exploring adding this to my model.

    Also see: the full list of ratings for all players.


    Coming in future columns:
    - Adjusted plus-minus recap for 2004-2005
    - Adjusted plus-minus ratings for the first half of 2006-2007
    - Individual offensive and defensive adjusted plus-minus ratings
    - Player wins and losses based on adjusted plus-minus ratings


    Special Thanks To:
    Dan Rosenbaum
    Roland Beech
    Vittorio Addona

    David Lewin is a 19 year-old college sophomore from Wayland, Massachusetts. He currently attends Macalester College in St. Paul, Minnesota where he plays football. He has contributed research and articles to Pro Football Prospectus 2006 and FootballOutsiders.com in addition to 82games.com. David is interested in a career in sports when he graduates and is always looking for interesting summer opportunities. A list of his articles can be found at 82games.com/lewin.htm. He can be reached at dlew33@yahoo.com
    http://82games.com/lewin2.htm
    "So, which one of you guys is going to come in second?" - Larry Bird before the 3 point contest. He won.


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    • #3
      Re: Plus-Minus explanation please

      Originally posted by pristinecollector View Post
      I searched for the answer but couldn't find one that didn't remind me of some science class in high school. Would someone please explain to me what the Plus-Minus is all about? I see it on the Pacers website under their "team" tab, and I see it a lot in the after game analysis, but I have no idea what it means.

      Thank you!
      More simply, it's the point differential when any individual player is on the floor. For example, at the start of the game, the score is tied. Let's say that Roy Hibbert plays for the first 6 minutes, and when he leaves the Pacers are up 14-10. Roy gets credited as having a +4 for that stretch. This is done for every other stint he plays, and compiled for a number at the end of the game. If Roy played four stretches, and the Pacers were +4, -2, -5, and +1 in those periods, then Roy would be credited with a -2 for the game, or the Pacers were outscored by 2 when Hibbert was on the floor.

      It's a stat that's always been heavily used in Hockey that's been adopted by the NBA. In hockey, it tends to be more useful because guys play as part of lines, generally being on the ice with the same teammates most of the time. It's marginally useful in the NBA, but it can be pretty misleading because of changing lineups and situations.

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      • #4
        Re: Plus-Minus explanation please

        Very clear explanations you two. I understand now. Thank you very much.

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        • #5
          Re: Plus-Minus explanation please

          Originally posted by count55 View Post
          In hockey, it tends to be more useful because guys play as part of lines, generally being on the ice with the same teammates most of the time. It's marginally useful in the NBA, but it can be pretty misleading because of changing lineups and situations.
          Thus, five-man +/- is much more useful, and 82games.com has a decent version of it.
          Why do the things that we treasure most, slip away in time
          Till to the music we grow deaf, to God's beauty blind
          Why do the things that connect us slowly pull us apart?
          Till we fall away in our own darkness, a stranger to our own hearts
          And life itself, rushing over me
          Life itself, the wind in black elms,
          Life itself in your heart and in your eyes, I can't make it without you

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