1. Welcome! Please take a few seconds to create your free account to post threads, make some friends, remove a few ads while surfing and much more. ClutchFans has been bringing fans together to talk Houston Sports since 1996. Join us!

What's the difference in our defense this year?

Discussion in 'Houston Rockets: Game Action & Roster Moves' started by durvasa, Mar 21, 2019.

  1. Spacemoth

    Spacemoth Member

    Joined:
    Jul 30, 2007
    Messages:
    9,909
    Likes Received:
    4,692
    I dunno how much he has left in the tank, but who would be opposed to bringing back Ariza at the league minimum next year? He can be our locker room enforcer and keep the young bucks in check.
     
  2. Easy

    Easy Boban Only Fan
    Supporting Member

    Joined:
    Jul 23, 2002
    Messages:
    38,305
    Likes Received:
    29,841
    I know. I'm just curious since this point was brought up. What is more important in terms of winning in general?

    It's kind of like asking, which is more important, defense or offense. Of course you always want to be good at both. But if there is some trade off involved, what should be the priority?
     
  3. heypartner

    heypartner Member

    Joined:
    Oct 27, 1999
    Messages:
    63,512
    Likes Received:
    59,010
    OK, just wanted to clarify whether you were able to cite others, because that data/post of yours was a response to the story where Spurs/Pops was reevaluating the importance of DREB, to possible learn to devalue it from Celtics success ... who were very good, but on the juggernaut Miami Big Three side of the draw, at the time.

    I defintiely remember that article. When you study the Spurs (along with that data analysis of that article), the truth is, they were always good at both. They always get at the ball.

    I think the idea of that article is contesting shots (include hounding post player and perimeter players prior to shot) is of vital importance, and it just naturally leads to good defense and inevitable turnovers....and contesting shots can hurt your DREB%...not necessarily a lot, but enough to find many great defensive teams who are good at both...and some who aren't great at DREB%.

    Then Indiania's top ranked defense and OKCs are anomalies over last two years, too. They are completely flipped so they are Top Tier in DRtg with significantly better TOV% than DREB%. So was several top defensive teams of Boston/Rivers era.

    This is why I don't think we can claim that "Twice" number, when arguably the best defense in a historical dynasty run is the complete opposite, and Pops' team (JVG, Sloan, Riley) are usually good at both equally. Dynasty's aren't anomaly, unless we really care about the lower half DRtg teams.

    I'd tend to say don't let the lower third of the DRtg team contribute to analysis, because if the top teams aren't twice, then who cares. I'd rerun the data to only include the teams who contend (maybe the 8-10 best each yr). There's too many great teams who are good at both, and teams who are opposite (like GSW, recent OKC, Ind and Boston teams in that historical data thread you referenced) -- for a twice number to pop out,
     
    Hakeemtheking and durvasa like this.
  4. heypartner

    heypartner Member

    Joined:
    Oct 27, 1999
    Messages:
    63,512
    Likes Received:
    59,010
    I don't share this fascination with minor analytics. I just said there are two many good teams who are balanced, and enough teams who are opposites for slight math results to be a driving factor here.

    But, just to play along, when it comes to defense, I'd run those numbers around only the Top 10 contenders. Don't let the shitty teams contribute to that analysis.

    The point made in the article referenced in the OP is contesting shots is the clear winner when it comes to top defenses. That's not in the boxscore, so we are left with how would active defenses who constantly hound the ball play out in secondary stats.

    How do you think contesting shots (to include the hounding of a post player and dribbler prior to shooting) would play out in terms of TOV% and DREB%? Do you think it matters to schemes if we find that one is slightly higher than the other, or is it just a curiousity for the fun of math?
     
    Easy and Relativist like this.
  5. Relativist

    Relativist Member

    Joined:
    Jul 26, 2000
    Messages:
    3,517
    Likes Received:
    241
    Off the top of my head, FG% seems like a logical proxy metric for contesting shots. It doesn't account for free throws however. Are there similar publicly-reported stats that might get at this?
     
  6. heypartner

    heypartner Member

    Joined:
    Oct 27, 1999
    Messages:
    63,512
    Likes Received:
    59,010
    eFG% is a Four Factor stat. But I wouldn't say contesting shots requires a FGA, just because NBA Stats website defines Shot Contesting stats as such. Coaches would prefer the shot never even get off.

    Thus, contesting the ability for the offense to get off good shots is the true meaning of Contesting Shots, so by that definition, it would include the following turnovers:
    • 24-second clock (a coaching favorite),
    • charges often prevent shots...like blocks do ... and are turnovers too...but, unlike Blocks, they also wipe out the FGA from boxscore.
    • any strips of the ball while making a move to shoot or drive (e.g., Harden's low post strips)
    • passing turnovers from stopping your dribble with nowhere to go or shoot
    • strips from double teams (player is attacked before he can shoot)
    • etc...
     
    Relativist likes this.
  7. Easy

    Easy Boban Only Fan
    Supporting Member

    Joined:
    Jul 23, 2002
    Messages:
    38,305
    Likes Received:
    29,841
    Not sure about hounding the ball and TOV%. But I know contesting shot is more important than defensive rebounding. This is one thing that is somewhat of a trade off. We see guys like Love and Westbrook stay off their man just so they can get to the defensive rebound. That's just bad defense.

    I do have curiosity for the fun of math though. Someone posted in another thread Morey's answer to the question whether fouling when up 3 points with 24 seconds left would yield better odds for winning. Morey said that fouling had a slightly higher advantage but not significant enough and it depends on perfect execution. That kind of things doesn't really matter much but they are just fun math for me.
     
  8. durvasa

    durvasa Member

    Joined:
    Feb 11, 2006
    Messages:
    38,895
    Likes Received:
    16,451

    "Anomaly" was too strong a word for me to use. You can have good defensive teams with mediocre or bad defensive rebounding -- there are many examples. That's just atypical. Historically, good defensive teams are more likely to be in the lower tier in forcing turnovers rather than in defensive rebounding. And its also true that bad defensive teams are more likely to be in the lower tier in defensive rebounding than in forcing turnovers.

    The data shows that overall defense correlates more to defensive rebounding performance than ability to force turnovers. I see this stronger relationship regardless of how I try to slice up the data. In a post further down in the original thread I linked to, I showed the correlations for playoff teams vs non-playoff teams over that 1974-2012 time period.

    I redid the analysis just now, for all teams from 2000-2001 season up to the current season. Same methodology: took the z-scores (standard deviations away from average) of each team's defensive rating and defensive four factors relative to rest of the league in each season, and then I looked at the relationships. Here are the plots of each of the four factors (x-axis) versus defensive rating (y-axis):

    [​IMG]

    Since you are particularly interested in the elite teams, here are the plots for the top 50 teams (by SRS) from 2000-2001 to the current season:

    [​IMG]

    Note that the relationships do not change that much, even when focusing on the really good teams. Take the Opponent ORB%_std and Opponent TOV%_std plots, above. Again, y-axis is z-score for defensive rating (lower is better), and x-axis is z-score for the opponent ORB% and opponent TOV% for those two plots, respectively. So, for the Opponent ORB%_std plot, the lower quadrant would be teams that were above average in defense and above average in defensive rebounding (lower ORB -> higher DRB). The point at (.708,-1.332) corresponds to the Warriors 73 win season (the highest SRS in this sample). That team was very good at overall defense (more than a standard deviation better than average) but not so good at defensive rebounding. But you can see from the plot that most of the really elite defensive teams are in that lower left quadrant -- they excelled at defensive rebounding.

    Now look at the Opponent TOV%_std plot. It's a little different. Here, the lower right quadrant corresponds to good team defense and being above average at forcing turnovers. The relationship is flatter. The top 4 defensive teams in the sample were above average in forcing turnovers, but there are several very good defensive teams (< -1 on y-axis) that were below average in forcing turnovers. By comparison, there were only 3 very good defensive teams that were below average in defensive rebounding.
     
    #48 durvasa, Mar 22, 2019
    Last edited: Mar 22, 2019
    Relativist and Easy like this.

Share This Page