Are we a real contender next year ?

[Moranis]

The bench is well below average, horrible actually. They need a front-line center with decent size that can anchor the defense and be of some value on offense, allowing Theis to play on a hopefully much improved second unit.

The bench was bellow average in his production this year, but horrible is maybe a little too much ...

https://stats.nba.com/teams/advanced/?SeasonType=Regular%20Season&StarterBench=Bench&dir=-1&sort=NET_RATING

Boston’s bench has been substantially above average, at seventh in the league.

We're 24th in bench minutes played. I'm not sure how they're determining "bench" O/DRTG here, but couldn't the net rating just be influenced by the fact that we play the bench with our best players a lot?

I don't think anyone can look at our bench and say it's top 7 in the league

I agree.  Smart, Kanter, Wanamaker, Williams, Williams, Ojeleye, and Langford/Edwards is not a very good bench, but they do mix well with the starters. 

I think you could argue that group on its own is in the top half of the league, but it would be hard to argue it is a top 10 bench as almost all of the playoff teams in the East have better benches (not Philly or Orlando - Brooklyn would if Irving was healthy, but doesn't without him) as do most of the Western ones, though they don't all have as good a starting lineup or a bench that fits as well (some do, just not all that have a collectively better bench). 

[Somebody]

The bench is well below average, horrible actually. They need a front-line center with decent size that can anchor the defense and be of some value on offense, allowing Theis to play on a hopefully much improved second unit.

The bench was bellow average in his production this year, but horrible is maybe a little too much ...

https://stats.nba.com/teams/advanced/?SeasonType=Regular%20Season&StarterBench=Bench&dir=-1&sort=NET_RATING

Boston’s bench has been substantially above average, at seventh in the league.

I don't think anyone can look at our bench and say it's top 7 in the league

Well, Danny Ainge did. I don’t have a link.

I’m surprised that you are so definite about this. I think that it’s a danmed difficult question, and it seems to me that it’s on you to say what’s wrong with the official stat. I’m not attached to it being ‘right’, either; it’s a snapshot, like any stat, with a confidence interval.

I myself am not very interested in ranking teams in this way - but very interested in what lineups give you a winning formula.

You can accumulate the raw +/- numbers for each individual in every game who doesn’t start, and in some sense you’ll get a number for the bench’s net. That strips away important contexts, though - like who’s playing together, whom they’re playing against, etc.

Context matters. Take the starters and replace Hayward with Ojeleye, for example. Now Semi is a poor rebounder and super-low with turnovers, and yet a Walker/Brown/Tatum/Ojeleye/Theis lineup rebounds at 52.5% compared to the starters’ 47.5%, while turnovers get worse, at +1% net compared to +4%.

None of the top-20 most used lineups had all subs. One of them had four, though:  Wanamaker/Smart/Tatum/Ojeleye/Kanter.  That lineup performed better than the starters:

Starters  Ortg 1.23/Drtg 1.13
W/S/T/O/K  Ortg 1.27/Drtg 1.08

- i.e., nine points better in a 100-possession game.

So should that group start? Probably not - context matters.

Do we have adjusted lineup data in the same way we have APM? If so we can have a decent ballpark of how good a lineup is as such data would take the factors you highlighted into account (or at least attempt to if there are collinearity issues).

I’ve never seen it, never even thought about it until you brought it up. I wonder if coaches are looking at anything like that?

Sample sizes would be all over the map, while even the most-used lineups don’t have a lot of possessions to work with.

I’ve got a high opinion of The Celtics bench 6-10. They all have usage %s under 20; maybe that partly explains the low estimation some fans have for them.

Imo our bench mob is strong defensively, which is great when the starting 5 has 4 players who're good offensively. They wouldn't be as good on other teams, but in our setup they're more than serviceable. And I think some front offices (most notably Houston) do look at those numbers, Morey has been on record saying that the Rockets use a proprietary version of APM in their player analysis. Don't think coaches use that type of data though, AFAIK coaches/playing staff use very specific stats that can help them on the court (eg. shooting % on certain spots of the floor, tracking data, etc). As for the hypothetical stat I brought up, I'm not sure if the statistical community has extended that concept to lineups.

[DefenseWinsChamps]

Smart and R Williams are both pretty dynamic game-changing players. They come in the game and the other team has to adjust to them. Having two players like that off the bench is pretty rare. Robert Williams has another level to go. Grant Williams is a solid team NBA player that doesn't hurt you. Ojeleye is a one-on-one defender that can make the opposing team's wing miserable on offense.

The only thing this team is missing is a high-level bench scorer--the Brad Wanamaker position. He's been better than this forum gives him credit, but he is a guy, nothing more.

If this team started Williams and Theis with Brown, Tatum, and Walker, and brought Hayward off the bench, people would feel a lot different about our bench. CBS rotations are essentially that, unless he is trying to force the development of the bench guys or get rest for the starters.

[BitterJim]

The bench is well below average, horrible actually. They need a front-line center with decent size that can anchor the defense and be of some value on offense, allowing Theis to play on a hopefully much improved second unit.

The bench was bellow average in his production this year, but horrible is maybe a little too much ...

https://stats.nba.com/teams/advanced/?SeasonType=Regular%20Season&StarterBench=Bench&dir=-1&sort=NET_RATING

Boston’s bench has been substantially above average, at seventh in the league.

We're 24th in bench minutes played. I'm not sure how they're determining "bench" O/DRTG here, but couldn't the net rating just be influenced by the fact that we play the bench with our best players a lot?

I don't think anyone can look at our bench and say it's top 7 in the league

I agree.  Smart, Kanter, Wanamaker, Williams, Williams, Ojeleye, and Langford/Edwards is not a very good bench, but they do mix well with the starters. 

I think you could argue that group on its own is in the top half of the league, but it would be hard to argue it is a top 10 bench as almost all of the playoff teams in the East have better benches (not Philly or Orlando - Brooklyn would if Irving was healthy, but doesn't without him) as do most of the Western ones, though they don't all have as good a starting lineup or a bench that fits as well (some do, just not all that have a collectively better bench).

Just to add to the extent that the starters and bench mixed: Marcus Smart, ostensibly our 6th man played the 2nd most total minutes, and started 39 of our 64 games (only coming off the bench in 14 of them). That also raises the biggest issue with our bench: while we're pretty good when the team is healthy, if Smart gets forced into the starting lineup then the best bench player is... Wanamaker? Maybe Kanter depending on the matchup? That's not good

So, although you could argue that the Wanamaker/Smart/Semi/Grant/Kanter lineup is a pretty good bench (especially with a group of starters like we have), when injuries push the bench to Wannamaker/(Green or Edwards)/Semi/Grant/Kanter it's one of the worst units in the league. And, yes, I know that most teams would have a weak bench if you removed their 6th man, but I think this team really needs a 7th man to push us over the top.  Get a combo guard or wing player that plays above average or good defense and shoots over 40% from 3, maybe with a little ability to create shots for themselves or others, and I think the bench could be a strength (and not be a liability when, not if, injuries crop up)