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Re: [APBR_analysis] Re: Team Ratings (adjusted for schedule strength)

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  • bchaikin@aol.com
    I m been telling people for years....Duncan is a Russell-caliber defensive presence. No one noticed much because Robinson was there, maybe now they will.  ...
    Message 1 of 18 , Dec 31, 2003
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      I'm been telling people for years....Duncan is a Russell-caliber defensive presence. No one noticed much because Robinson was there, maybe now they will.  :)

      people noticed - duncan's been all-D 1st team 5 straight seasons...

      the parallels in the careers of tim duncan and david robinson are actually uncanny, considering the two players played with the same franchise almost a decade apart (8 years to be exact). both were/are stellar defenders - duncan's been in the league for 6 years and was all-D 1st team 5 years and all-D 2nd team the other year. robinson was all-D 1st team 4 of his 1st 7 years, all-D 2nd team the other 3 (olajuwon was 1st each time) and was one season the def player of the yr (9192). in duncan's first 6 years in the league the spurs had the league's best defensive FG% twice, and the 2nd, 3rd, 4th, and 5th best once. in robinson's first 6 years in the league the spurs had the league's best defensive FG% twice, the 3rd best once, the 4th best twice, and the 7th best once. duncan appears to be everything on defense that robinson was, and has a chance to be better for longer on that end of the court if his health holds out...

      for each's first 6 years in the league here is their comparison on offense (and more):

                      min/g    g   fgm/g   fga/g    fg%   fta/g   ft%
      duncan        39    451   8.7     17.1   .510    7.6  .710
      robinson      38    475   9.1      17.3   .527   9.9  .744

                       reb/g   ast/g   pf/g   st/g   to/g   bs/g  pts/g  
      duncan       12.3     3.2     2.9   0.8     3.1    2.5    22.9
      robinson      11.7    3.1     3.0   1.7     3.0     3.6   25.7

      could two great players be more evenly talented their 1st six years in the league, let alone play for the same franchise? kinda great that their careers overlapped for a few seasons...

      bob chaikin
      bchaikin@...
    • Michael Tamada
      This is nice stuff, but do you also adjust for home vs away games? I would guess that on average it s probably even more important than opponent s strength in
      Message 2 of 18 , Jan 2, 2004
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        This is nice stuff, but do you also adjust for home vs away
        games? I would guess that on average it's probably even
        more important than opponent's strength in terms of helping
        us to predict who's going to win a game.

        By the end of the season, teams will have all played half
        their games at home and half away of course, so in that
        sense the home-away thing becomes largely irrelevant at the
        end of the season. But even then it may still have some
        value, because teams don't play perfectly balanced home-and-
        away schedules.

        --MKT


        -----Original Message-----
        From: ssims22000 [mailto:ssims2@...]
        Sent: Tuesday, December 30, 2003 9:14 AM
        To: APBR_analysis@yahoogroups.com
        Subject: [APBR_analysis] Team Ratings (adjusted for schedule strength)


        These ratings use a pythagorean approximation (exponent 14), with
        offensive & defensive ratings adjusted as follows:

        ORate = Base ORate * Opp. Opp. ORate / Opp. DRate
        DRate = Base DRate * Opp. Opp. DRate / Opp. ORate

        the ORates and DRates listed are adjusted to leage average = 100.
        XWins is expected wins out of 82. Ratings are through Dec. 24.

        Team ORate DRate XWins
        SAC 110.1 101.7 61.7
        SAN 97.6 90.3 61.4
        LAL 105.6 98.9 58.7
        MIN 103.4 98.4 54.7
        DAL 107.3 102.4 54.2
        IND 98.6 94.9 51.7
        DEN 101.5 98.0 51.0
        DET 98.4 95.3 50.1
        MEM 100.8 98.7 47.1
        HOU 96.8 94.8 46.9
        UTA 102.6 101.2 44.9
        NJN 96.9 96.0 43.9
        NOR 99.8 99.1 42.9
        MIL 100.9 100.5 42.1
        BOS 101.4 101.0 42.1
        GSW 101.3 101.0 41.8
        SEA 104.0 104.3 40.1
        PHI 98.6 99.6 38.1
        LAC 101.1 102.5 37.0
        POR 104.0 106.2 35.1
        PHO 98.7 101.6 32.8
        CLE 97.5 101.0 31.1
        NYK 95.8 99.8 29.6
        TOR 95.3 99.6 28.8
        MIA 95.7 100.3 28.0
        WAS 95.2 101.4 24.0
        ORL 99.4 106.0 23.8
        ATL 97.2 104.6 21.5
        CHI 95.1 102.8 20.6

        Some comments: Sacramento has an extremely high offensive rating,
        while San Antonio has an extremely good defensive rating. Both
        would rate as the best all-time, for a whole season, and so are
        probably unsustainable for such a period. Sacramento's defense has
        been lax (they were among the very best last year), but with their
        offensive efficiency, they haven't needed to be better. San Antonio
        has struggled offensively, and so they have probably expended more
        consistent effort on defense than they would need to if they were
        all clicking offensively.
        Cleveland rates higher than expected - it seems they are
        underachieving. Toronto, conversely, is way low for a .500 team -
        they would be the best overachievers so far.




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      • ssims22000
        Hi, I haven t yet attempted to adjust for home vs. away. I know it would make a big difference for Portland - at the time of these ratings, the Blazers had
        Message 3 of 18 , Jan 3, 2004
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          Hi,

          I haven't yet attempted to adjust for home vs. away. I know it
          would make a big difference for Portland - at the time of these
          ratings, the Blazers had played about twice as many home games as
          away games. By the end of the season, it should be a wash - most
          teams play each other teams 2 or 4 times, which means equal home and
          away games vs. those teams. In fact, the Western teams will have
          completely balanced schedules (2 games vs. each East team & 4 games
          vs. each West team). Now, though, there is significant imbalance.

          The only good way I can think of to handle this is to calculate
          home and away ratings for each team, and use these in the SoS
          calculations. I don't have access to that kind of breakdown (maybe
          Roland does).


          --- In APBR_analysis@yahoogroups.com, "Michael Tamada" <tamada@o...>
          wrote:
          > This is nice stuff, but do you also adjust for home vs away
          > games? I would guess that on average it's probably even
          > more important than opponent's strength in terms of helping
          > us to predict who's going to win a game.
          >
          > By the end of the season, teams will have all played half
          > their games at home and half away of course, so in that
          > sense the home-away thing becomes largely irrelevant at the
          > end of the season. But even then it may still have some
          > value, because teams don't play perfectly balanced home-and-
          > away schedules.
          >
          > --MKT
          >
          >
        • Michael Tamada
          I was thinking of a simpler, cruder home-away correction. Although some teams seem to thrive at home and wilt away from it (Utah) and others seem to be road
          Message 4 of 18 , Jan 5, 2004
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            I was thinking of a simpler, cruder home-away correction. Although
            some teams seem to thrive at home and wilt away from it (Utah) and
            others seem to be road warriors as good on the road as at home (Boston,
            Seattle), I was thinking in terms of simply giving a single universal
            home-away correction that would be applied to every home team's offense
            rating or defense rating (or both, but I think this wouldn't really matter,
            because it'd simply be a constant to be added or subtracted).

            We would still need some home-away split data, but even if that's
            unavailable we could estimate what the home bonus should be: in
            most years, NBA teams win about 2/3 of their home games (I haven't
            looked at this year's data). Comparing a .667 team to a .500 team,
            how much better would its offense have to be to move it from .500
            to .667? (Or equivalently, how much better would its defense have
            to be?) Whatever that figure is, that's the home bonus to give
            to the home team's offensive rating (or defensive rating).

            Crude but simple and I think it would significantly help correct
            for teams which have had schedules which were either (a) unbalanced
            with respect to home and away games or (b) balanced with respect
            to home and away, but unbalanced in terms of having tough or easy
            road opponents, and vice-versa at home.


            --MKT


            -----Original Message-----
            From: ssims22000 [mailto:ssims2@...]
            Sent: Saturday, January 03, 2004 1:44 PM


            Hi,

            I haven't yet attempted to adjust for home vs. away. I know it
            would make a big difference for Portland - at the time of these
            ratings, the Blazers had played about twice as many home games as
            away games. By the end of the season, it should be a wash - most
            teams play each other teams 2 or 4 times, which means equal home and
            away games vs. those teams. In fact, the Western teams will have
            completely balanced schedules (2 games vs. each East team & 4 games
            vs. each West team). Now, though, there is significant imbalance.

            The only good way I can think of to handle this is to calculate
            home and away ratings for each team, and use these in the SoS
            calculations. I don't have access to that kind of breakdown (maybe
            Roland does).


            --- In APBR_analysis@yahoogroups.com, "Michael Tamada" <tamada@o...>
            wrote:
            > This is nice stuff, but do you also adjust for home vs away
            > games? I would guess that on average it's probably even
            > more important than opponent's strength in terms of helping
            > us to predict who's going to win a game.
            >
            > By the end of the season, teams will have all played half
            > their games at home and half away of course, so in that
            > sense the home-away thing becomes largely irrelevant at the
            > end of the season. But even then it may still have some
            > value, because teams don't play perfectly balanced home-and-
            > away schedules.
            >
            > --MKT
            >
            >





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          • Michael Tamada
            ... From: Michael Tamada Sent: Monday, January 05, 2004 9:44 AM ... Correcting myself, I think the appropriate comparison is a .667 team to a .333 team. That
            Message 5 of 18 , Jan 5, 2004
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              -----Original Message-----
              From: Michael Tamada
              Sent: Monday, January 05, 2004 9:44 AM

              >most years, NBA teams win about 2/3 of their home games (I haven't
              >looked at this year's data). Comparing a .667 team to a .500 team,
              >how much better would its offense have to be to move it from .500
              >to .667? (Or equivalently, how much better would its defense have
              >to be?) Whatever that figure is, that's the home bonus to give
              >to the home team's offensive rating (or defensive rating).

              Correcting myself, I think the appropriate comparison is a .667
              team to a .333 team. That would give us the size of the bonus
              to give to the home team.


              --MKT
            • Dean LaVernge
              ... Here is the Home/Away records for the NBA (2004 Season through games of 1/4/2004) Home Road Season Wins Losses % Wins Losses %
              Message 6 of 18 , Jan 5, 2004
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                On 5 Jan 2004 at 9:43, Michael Tamada wrote:

                >
                > I was thinking of a simpler, cruder home-away correction. Although
                > some teams seem to thrive at home and wilt away from it (Utah) and
                > others seem to be road warriors as good on the road as at home (Boston,
                > Seattle), I was thinking in terms of simply giving a single universal
                > home-away correction that would be applied to every home team's offense
                > rating or defense rating (or both, but I think this wouldn't really matter,
                > because it'd simply be a constant to be added or subtracted).
                >
                > We would still need some home-away split data, but even if that's
                > unavailable we could estimate what the home bonus should be: in
                > most years, NBA teams win about 2/3 of their home games (I haven't
                > looked at this year's data). Comparing a .667 team to a .500 team,
                > how much better would its offense have to be to move it from .500
                > to .667? (Or equivalently, how much better would its defense have
                > to be?) Whatever that figure is, that's the home bonus to give
                > to the home team's offensive rating (or defensive rating).
                >
                > Crude but simple and I think it would significantly help correct
                > for teams which have had schedules which were either (a) unbalanced
                > with respect to home and away games or (b) balanced with respect
                > to home and away, but unbalanced in terms of having tough or easy
                > road opponents, and vice-versa at home.
                >
                >
                > --MKT
                >

                Here is the Home/Away records for the NBA (2004 Season through games of 1/4/2004)

                Home Road
                Season Wins Losses % Wins Losses %
                1947 202 129 0.610 129 202 0.390
                1948 107 85 0.557 85 107 0.443
                1949 212 132 0.616 132 212 0.384
                1950 351 167 0.678 167 351 0.322
                1951 254 85 0.749 85 254 0.251
                1952 213 80 0.727 80 213 0.273
                1953 195 83 0.701 83 195 0.299
                1954 151 84 0.643 84 151 0.357
                1955 139 59 0.702 59 139 0.298
                1956 141 80 0.638 80 141 0.362
                1957 172 76 0.694 76 172 0.306
                1958 150 85 0.638 85 150 0.362
                1959 148 80 0.649 80 148 0.351
                1960 149 84 0.639 84 149 0.361
                1961 156 85 0.647 85 156 0.353
                1962 166 107 0.608 107 166 0.392
                1963 184 109 0.628 109 184 0.372
                1964 185 126 0.595 126 185 0.405
                1965 178 125 0.587 125 178 0.413
                1966 197 89 0.689 89 197 0.311
                1967 193 128 0.601 128 193 0.399
                1968 241 182 0.570 182 241 0.430
                1969 315 206 0.605 206 315 0.395
                1970 312 207 0.601 207 313 0.398
                1971 402 262 0.605 262 402 0.395
                1972 385 277 0.582 277 385 0.418
                1973 393 268 0.595 268 393 0.405
                1974 410 262 0.610 262 410 0.390
                1975 472 266 0.640 266 472 0.360
                1976 484 254 0.656 354 484 0.422
                1977 634 268 0.703 293 609 0.325
                1978 610 292 0.676 292 610 0.324
                1979 600 302 0.665 302 600 0.335
                1980 588 314 0.652 314 588 0.348
                1981 586 357 0.621 357 586 0.379
                1982 565 378 0.599 378 565 0.401
                1983 585 358 0.620 358 585 0.380
                1984 640 303 0.679 303 640 0.321
                1985 601 342 0.637 342 601 0.363
                1986 617 326 0.654 326 617 0.346
                1987 627 316 0.665 316 627 0.335
                1988 640 303 0.679 303 640 0.321
                1989 694 331 0.677 331 694 0.323
                1990 713 394 0.644 394 713 0.356
                1991 730 377 0.659 377 730 0.341
                1992 689 408 0.628 408 699 0.369
                1993 676 431 0.611 431 676 0.389
                1994 677 430 0.612 430 677 0.388
                1995 661 446 0.597 446 661 0.403
                1996 718 471 0.604 471 718 0.396
                1997 684 505 0.575 505 684 0.425
                1998 708 481 0.595 481 708 0.405
                1999 452 273 0.623 273 452 0.377
                2000 726 463 0.611 452 737 0.380
                2001 711 478 0.598 478 711 0.402
                2002 703 486 0.591 480 709 0.404
                2003 747 442 0.628 442 747 0.372
                2004 297 179 0.624 179 297 0.376
                NBA 25136 14716 0.631 14824 25139 0.371

                DeanL
              • Michael Tamada
                Thanks, clearly my figure of 2/3 home wins was based on 1970s-1980s memories, in recent years the figure s been more like 3/5. There s a lot of little detailed
                Message 7 of 18 , Jan 6, 2004
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                  Thanks, clearly my figure of 2/3 home wins was based on 1970s-1980s
                  memories, in recent years the figure's been more like 3/5.

                  There's a lot of little detailed questions to be answered, such as
                  which Home Win% figure to use, let's just pick this year's current
                  value of 62%.

                  Using ssims' ORate and DRate numbers, that corresponds to a team
                  having approximately a 3.5 point advantage, in terms of ORate -
                  DRate difference.

                  So if a team has played 12 home games and 8 away games, it's got
                  a 4-game imbalance, worth a cumulative 4*3.5 point ORate-DRate
                  difference = 14, which spread over its 20 games is 0.7 points
                  of ORate-DRate differential.

                  So if the initial rating has the team appearing to be a .500
                  team with ORate = 100 and DRate = 100, an estimate which
                  corrects for its excessive home games would be ORate = 99.3
                  (or, the .7 points could be split evenly between ORate and DRate).

                  This is a crude measure of course;, if we had home-road splits
                  of O and D, we could do separate corrections for ORate and DRate.

                  And for theoretical correctness we should apply the same Home-
                  Road correction to the Opponent's ratings, as well as the
                  Opponents' Opponents' ratings.

                  Better still would be to apply the correction to individual
                  game scores, rather than each team's aggregate totals; and
                  to base the ratings on the outcomes of the individual games
                  rather than the aggregate season totals; and to permit
                  individual teams to have differing home bonuses instead of
                  assigning all teams a 3.5 home bonus; and to solve the
                  simultaneous equations for looking at opponents'
                  opponents' opponents' ... ad infinitum; and etc. etc.

                  But those procedures would require a lot more data and a lot
                  more work. This crude home-road correction is simple and
                  I would guess cleans up a good chunk of the home-road bias.



                  --MKT




                  -----Original Message-----
                  From: Dean LaVernge [mailto:deanlav@...]
                  Sent: Monday, January 05, 2004 8:24 PM
                  To: APBR_analysis@yahoogroups.com
                  Subject: RE: [APBR_analysis] Re: Team Ratings (adjusted for schedule
                  strength)


                  On 5 Jan 2004 at 9:43, Michael Tamada wrote:

                  >
                  > I was thinking of a simpler, cruder home-away correction. Although
                  > some teams seem to thrive at home and wilt away from it (Utah) and
                  > others seem to be road warriors as good on the road as at home (Boston,
                  > Seattle), I was thinking in terms of simply giving a single universal
                  > home-away correction that would be applied to every home team's offense
                  > rating or defense rating (or both, but I think this wouldn't really matter,
                  > because it'd simply be a constant to be added or subtracted).
                  >
                  > We would still need some home-away split data, but even if that's
                  > unavailable we could estimate what the home bonus should be: in
                  > most years, NBA teams win about 2/3 of their home games (I haven't
                  > looked at this year's data). Comparing a .667 team to a .500 team,
                  > how much better would its offense have to be to move it from .500
                  > to .667? (Or equivalently, how much better would its defense have
                  > to be?) Whatever that figure is, that's the home bonus to give
                  > to the home team's offensive rating (or defensive rating).
                  >
                  > Crude but simple and I think it would significantly help correct
                  > for teams which have had schedules which were either (a) unbalanced
                  > with respect to home and away games or (b) balanced with respect
                  > to home and away, but unbalanced in terms of having tough or easy
                  > road opponents, and vice-versa at home.
                  >
                  >
                  > --MKT
                  >

                  Here is the Home/Away records for the NBA (2004 Season through games of 1/4/2004)

                  Home Road
                  Season Wins Losses % Wins Losses %
                  1947 202 129 0.610 129 202 0.390
                  1948 107 85 0.557 85 107 0.443
                  1949 212 132 0.616 132 212 0.384
                  1950 351 167 0.678 167 351 0.322
                  1951 254 85 0.749 85 254 0.251
                  1952 213 80 0.727 80 213 0.273
                  1953 195 83 0.701 83 195 0.299
                  1954 151 84 0.643 84 151 0.357
                  1955 139 59 0.702 59 139 0.298
                  1956 141 80 0.638 80 141 0.362
                  1957 172 76 0.694 76 172 0.306
                  1958 150 85 0.638 85 150 0.362
                  1959 148 80 0.649 80 148 0.351
                  1960 149 84 0.639 84 149 0.361
                  1961 156 85 0.647 85 156 0.353
                  1962 166 107 0.608 107 166 0.392
                  1963 184 109 0.628 109 184 0.372
                  1964 185 126 0.595 126 185 0.405
                  1965 178 125 0.587 125 178 0.413
                  1966 197 89 0.689 89 197 0.311
                  1967 193 128 0.601 128 193 0.399
                  1968 241 182 0.570 182 241 0.430
                  1969 315 206 0.605 206 315 0.395
                  1970 312 207 0.601 207 313 0.398
                  1971 402 262 0.605 262 402 0.395
                  1972 385 277 0.582 277 385 0.418
                  1973 393 268 0.595 268 393 0.405
                  1974 410 262 0.610 262 410 0.390
                  1975 472 266 0.640 266 472 0.360
                  1976 484 254 0.656 354 484 0.422
                  1977 634 268 0.703 293 609 0.325
                  1978 610 292 0.676 292 610 0.324
                  1979 600 302 0.665 302 600 0.335
                  1980 588 314 0.652 314 588 0.348
                  1981 586 357 0.621 357 586 0.379
                  1982 565 378 0.599 378 565 0.401
                  1983 585 358 0.620 358 585 0.380
                  1984 640 303 0.679 303 640 0.321
                  1985 601 342 0.637 342 601 0.363
                  1986 617 326 0.654 326 617 0.346
                  1987 627 316 0.665 316 627 0.335
                  1988 640 303 0.679 303 640 0.321
                  1989 694 331 0.677 331 694 0.323
                  1990 713 394 0.644 394 713 0.356
                  1991 730 377 0.659 377 730 0.341
                  1992 689 408 0.628 408 699 0.369
                  1993 676 431 0.611 431 676 0.389
                  1994 677 430 0.612 430 677 0.388
                  1995 661 446 0.597 446 661 0.403
                  1996 718 471 0.604 471 718 0.396
                  1997 684 505 0.575 505 684 0.425
                  1998 708 481 0.595 481 708 0.405
                  1999 452 273 0.623 273 452 0.377
                  2000 726 463 0.611 452 737 0.380
                  2001 711 478 0.598 478 711 0.402
                  2002 703 486 0.591 480 709 0.404
                  2003 747 442 0.628 442 747 0.372
                  2004 297 179 0.624 179 297 0.376
                  NBA 25136 14716 0.631 14824 25139 0.371

                  DeanL






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                • ssims22000
                  I did a few calculations of my own on a schedule strength modifier. ... I used .625 (or 5/8). Using the Pythagorean approximation, and assuming Offense = 1,
                  Message 8 of 18 , Jan 8, 2004
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                    I did a few calculations of my own on a schedule strength
                    modifier.

                    --- In APBR_analysis@yahoogroups.com, "Michael Tamada" <tamada@o...>
                    wrote:
                    > There's a lot of little detailed questions to be answered, such as
                    > which Home Win% figure to use, let's just pick this year's current
                    > value of 62%.
                    >
                    I used .625 (or 5/8). Using the Pythagorean approximation, and
                    assuming Offense = 1, then

                    0.625 = (1 ^ EXP) / ( 1 ^ EXP + DEF ^ EXP)

                    where EXP is the exponent you are using. I use 14, since it is
                    about average for the last few seasons. Solving for DEF (the team
                    defensive rating as a percentage):

                    DEF = ( ( 1 / 0.625 ) - 1 ) ^ ( 1 / 14 )

                    or DEF = 0.9641701. Balancing the defensive and offensive ratios
                    around 100, I get Offense = 101.82417 and Defense = 98.20851.
                    These are the expected offensive and defensive ratings for an
                    average team at home. On the road, reverse the two. This gives a
                    3.6 point difference, pretty close to what you found.

                    > Using ssims' ORate and DRate numbers, that corresponds to a team
                    > having approximately a 3.5 point advantage, in terms of ORate -
                    > DRate difference.
                    >
                    > So if a team has played 12 home games and 8 away games, it's got
                    > a 4-game imbalance, worth a cumulative 4*3.5 point ORate-DRate
                    > difference = 14, which spread over its 20 games is 0.7 points
                    > of ORate-DRate differential.
                    >
                    > So if the initial rating has the team appearing to be a .500
                    > team with ORate = 100 and DRate = 100, an estimate which
                    > corrects for its excessive home games would be ORate = 99.3
                    > (or, the .7 points could be split evenly between ORate and DRate).
                    >
                    > This is a crude measure of course;, if we had home-road splits
                    > of O and D, we could do separate corrections for ORate and DRate.
                    >
                    > And for theoretical correctness we should apply the same Home-
                    > Road correction to the Opponent's ratings, as well as the
                    > Opponents' Opponents' ratings.
                    >

                    What I will do when I have the time is change the weights in the
                    formulas that calculate the schedule strength. Instead of each game
                    being weighted as 1, a home game will weigh as .982 for offensive
                    strength and 1.018 for defensive strength, and road games will weigh
                    as the opposite.


                    > Better still would be to apply the correction to individual
                    > game scores, rather than each team's aggregate totals; and
                    > to base the ratings on the outcomes of the individual games
                    > rather than the aggregate season totals; and to permit
                    > individual teams to have differing home bonuses instead of
                    > assigning all teams a 3.5 home bonus; and to solve the
                    > simultaneous equations for looking at opponents'
                    > opponents' opponents' ... ad infinitum; and etc. etc.
                    >
                    > But those procedures would require a lot more data and a lot
                    > more work. This crude home-road correction is simple and
                    > I would guess cleans up a good chunk of the home-road bias.
                    >
                    >
                    >
                    > --MKT
                    >
                  • ssims22000
                    The team ratings are updated through Jan. 27. I didn t have time to include a home/away modifier, so all ratings are calculated the same as before. ... with
                    Message 9 of 18 , Jan 28, 2004
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                      The team ratings are updated through Jan. 27. I didn't have time
                      to include a home/away modifier, so all ratings are calculated the
                      same as before.

                      --- In APBR_analysis@yahoogroups.com, "ssims22000" <ssims2@i...>
                      wrote:
                      > These ratings use a pythagorean approximation (exponent 14),
                      with
                      > offensive & defensive ratings adjusted as follows:
                      >
                      > ORate = Base ORate * Opp. Opp. ORate / Opp. DRate
                      > DRate = Base DRate * Opp. Opp. DRate / Opp. ORate
                      >
                      > the ORates and DRates listed are adjusted to leage average = 100.
                      > XWins is expected wins out of 82. Ratings are through Jan. 27.

                      I've also included a Floor Rating (basically, team floor %
                      adjusted for strength of schedule and league average. You can
                      really tell the teams that rely heavily on the three (their floor
                      ratings are much lower than their offensive ratings).


                      Team ORate DRate XWins OFlR DFlR
                      SAN 97.3 90.7 59.6 98.9 91.8
                      SAC 108.1 101.0 59.3 105.9 102.0
                      MIN 103.6 98.0 56.1 105.3 97.7
                      LAL 102.8 98.1 54.2 104.8 98.4
                      HOU 98.1 93.5 54.2 96.2 93.0
                      IND 99.3 94.7 54.1 98.8 95.8
                      DAL 108.9 103.9 54.1 107.3 102.9
                      DET 99.5 95.3 53.2 100.4 96.0
                      MEM 102.4 99.6 48.8 102.3 100.0
                      DEN 100.7 98.3 47.8 101.5 99.6
                      MIL 102.2 100.7 45.0 102.2 100.9
                      NJN 96.7 95.4 44.8 97.1 95.0
                      NOR 99.5 99.1 42.2 98.1 98.8
                      UTA 101.4 101.6 40.6 104.1 101.1
                      BOS 100.1 100.4 40.2 97.9 99.1
                      SEA 104.1 105.1 38.3 99.9 104.0
                      GSW 100.3 101.7 37.0 100.3 101.1
                      LAC 102.3 103.8 36.9 102.9 104.4
                      NYK 98.2 99.8 36.3 96.7 99.9
                      PHI 97.3 99.3 35.4 97.9 98.4
                      PHO 98.3 101.0 33.5 98.5 100.4
                      POR 102.4 105.8 31.6 103.7 105.6
                      CLE 97.5 100.8 31.5 99.7 100.2
                      MIA 97.0 100.8 30.3 96.5 100.6
                      TOR 93.9 98.1 28.7 93.3 99.8
                      ORL 101.8 108.0 24.8 101.2 107.7
                      WAS 94.5 100.9 23.6 95.5 100.8
                      ATL 96.2 102.8 23.2 97.1 102.8
                      CHI 95.1 102.1 22.3 95.4 102.1

                      Comments: I mentioned Sacramento's very high offensive efficiency
                      (110 a month ago) and San Antonio's excellent defensive efficiency
                      (90 a month ago) as being unsustainable. Well, Sacramento's offense
                      has fallen off by two points (and their sub-par defense improved by
                      one), so I was right there. San Antonio's defense has yet to fall
                      off significantly, though, and their offense continues to be among
                      the NBA's least efficient. San Antonio also faced the weakest first
                      half schedule of any Western team (Sacramento faced the second-
                      weakest), so the true test will be the second half. These two teams
                      have yet to play each other, so we have four games between the
                      irresistable force and the immovable object to look forward too.

                      Other strong offenses & defenses: Houston has improved its numbers
                      by about two in either direction, much of that presumably
                      attributable to Yao's continued development. Anyone else think this
                      team could be very dangerous come playoff time? Their achilles heel
                      is their low offensive floor% - when it comes to crunch time, can
                      their offense come through with the needed buckets? Dallas is back
                      on top of the NBA's offenses, though they're doing it differently
                      this year. Their shooting is down (with Walker throwing up all
                      those bricks, that's a given), but their offensive rebounding is way
                      up, thanks to Jamison, Fortson, and Howard, primarily. That makes
                      their offensive numbers much more sustainable, in my mind, than
                      Sacramento's, which are based on continued amazing shooting from
                      within and without the arc.

                      Other notes: Orlando's defense is on pace to be one of the worst in
                      NBA history. Seattle is taking 30% of their shots behind the arc,
                      resulting in a floor rating of 100 and an offensive rating of 104.
                    • igor eduardo küpfer
                      ... From: ssims22000 To: Sent: Wednesday, January 28, 2004 5:08 PM Subject: [APBR_analysis] Re: Team
                      Message 10 of 18 , Jan 28, 2004
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                        ----- Original Message -----
                        From: "ssims22000" <ssims2@...>
                        To: <APBR_analysis@yahoogroups.com>
                        Sent: Wednesday, January 28, 2004 5:08 PM
                        Subject: [APBR_analysis] Re: Team Ratings (adjusted for schedule strength)


                        > The team ratings are updated through Jan. 27. I didn't have time
                        > to include a home/away modifier, so all ratings are calculated the
                        > same as before.
                        >

                        I may have missed this the first time around, but how are you adjusting for
                        opponent strength? Just this season's performance, or are you including
                        previous season(s)?

                        ed
                      • Mike G
                        ... I m curious whether your ratings add anything beyond what Jeff Sagarin offers: http://www.usatoday.com/sports/sagarin/nba0304.htm He uses
                        Message 11 of 18 , Jan 29, 2004
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                          --- In APBR_analysis@yahoogroups.com, "ssims22000" <ssims2@i...>
                          wrote:
                          > The team ratings are updated through Jan. 27. I didn't have time
                          > to include a home/away modifier, so all ratings are calculated the
                          > same as before.

                          I'm curious whether your ratings add anything beyond what Jeff
                          Sagarin offers:

                          http://www.usatoday.com/sports/sagarin/nba0304.htm

                          He uses point-differential, rather than off/def efficiencies. It
                          seems to me a team's scoring differential is going to be equivalent
                          to their efficiency differential. Whether they are better on
                          offense or on defense is another matter; but whether team A is
                          better than team B, does one need that distinction?

                          Sagarin does use home/away in his SOS deduction. He ranks the
                          Kings' SOS as #24 in the league (Spurs at #17).

                          In your eXpected Wins column, I guess you are assuming a balanced
                          schedule for everyone ?

                          >
                          >
                          >
                          > Team ORate DRate XWins OFlR DFlR
                          > SAN 97.3 90.7 59.6 98.9 91.8
                          > SAC 108.1 101.0 59.3 105.9 102.0
                          > MIN 103.6 98.0 56.1 105.3 97.7
                          > LAL 102.8 98.1 54.2 104.8 98.4
                          > HOU 98.1 93.5 54.2 96.2 93.0
                          > IND 99.3 94.7 54.1 98.8 95.8
                          > DAL 108.9 103.9 54.1 107.3 102.9
                          > DET 99.5 95.3 53.2 100.4 96.0
                          > MEM 102.4 99.6 48.8 102.3 100.0
                          > DEN 100.7 98.3 47.8 101.5 99.6
                          > MIL 102.2 100.7 45.0 102.2 100.9
                          > NJN 96.7 95.4 44.8 97.1 95.0
                          > NOR 99.5 99.1 42.2 98.1 98.8
                          > UTA 101.4 101.6 40.6 104.1 101.1
                          > BOS 100.1 100.4 40.2 97.9 99.1
                          > SEA 104.1 105.1 38.3 99.9 104.0
                          > GSW 100.3 101.7 37.0 100.3 101.1
                          > LAC 102.3 103.8 36.9 102.9 104.4
                          > NYK 98.2 99.8 36.3 96.7 99.9
                          > PHI 97.3 99.3 35.4 97.9 98.4
                          > PHO 98.3 101.0 33.5 98.5 100.4
                          > POR 102.4 105.8 31.6 103.7 105.6
                          > CLE 97.5 100.8 31.5 99.7 100.2
                          > MIA 97.0 100.8 30.3 96.5 100.6
                          > TOR 93.9 98.1 28.7 93.3 99.8
                          > ORL 101.8 108.0 24.8 101.2 107.7
                          > WAS 94.5 100.9 23.6 95.5 100.8
                          > ATL 96.2 102.8 23.2 97.1 102.8
                          > CHI 95.1 102.1 22.3 95.4 102.1
                          >
                        • ssims22000
                          ... time ... the ... equivalent ... The purpose of my ratings is a little different than Sagarin s. If you just want to look at which team is better, and that
                          Message 12 of 18 , Jan 29, 2004
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                            --- In APBR_analysis@yahoogroups.com, "Mike G" <msg_53@h...> wrote:
                            > --- In APBR_analysis@yahoogroups.com, "ssims22000" <ssims2@i...>
                            > wrote:
                            > > The team ratings are updated through Jan. 27. I didn't have
                            time
                            > > to include a home/away modifier, so all ratings are calculated
                            the
                            > > same as before.
                            >
                            > I'm curious whether your ratings add anything beyond what Jeff
                            > Sagarin offers:
                            >
                            > http://www.usatoday.com/sports/sagarin/nba0304.htm
                            >
                            > He uses point-differential, rather than off/def efficiencies. It
                            > seems to me a team's scoring differential is going to be
                            equivalent
                            > to their efficiency differential. Whether they are better on
                            > offense or on defense is another matter; but whether team A is
                            > better than team B, does one need that distinction?
                            >
                            The purpose of my ratings is a little different than Sagarin's.
                            If you just want to look at which team is better, and that is all
                            you care about, use his ratings - his rating model is a lot more
                            sophisticated. After all, I am just using a clunky Pythagorean
                            approximation. A bell curve like Dean uses would be more accurate,
                            but it would require me to use a matrix of game scores, and that's a
                            bit too time-consuming for me right now. All I want out of my
                            overall team ratings is an approximation of how well each team is
                            doing. One small note - the results are a bit different because I
                            don't set a team's possessions equal to its opponents' possessions.
                            So a team which, for some reason, has 0.7 fewer possessions / game
                            than its opponents will rate better than it would if pure
                            differential were used. I do this because using pure possessions
                            like this gives more accurate offensive & defensive ratings, and
                            that's what I'm really after here.
                            Offensive and Defensive ratings, in my opinion, give more useful
                            information about a team than just a rating saying how "good" the
                            team is. These ratings start to answer the question of how a team
                            is good (or bad). For instance, someone just looking at the Sagarin
                            ratings for Orlando might be bewildered as to how a team that was in
                            the playoffs a year ago could be so bad. Look at their defensive
                            rating, though. Here we see some epic-level bad defense. OK, that
                            explains things. If you want to know why they are so bad
                            defensively, you'd have to go deeper than this. I have some other
                            quick stats that can help elucidate the factors that make an offense
                            or defense perform the way it does (I took most of these from Dean's
                            book, as well): true shooting percentage (we're all familiar with
                            this one, right?), free throw ratio (as Dean defines it, free throws
                            MADE / field goals attempted - you could combine these first two
                            into a scoring efficiency number, as well, though looking at them
                            separately tells you more about how they score), offensive
                            rebounding percentage & turnover percentage (turnovers /
                            possessions). These cover all of the factors going into an
                            offensive (or defensive) rating. The floor percentage (or floor
                            rating, as I have it here - a modification of Dean's formula) is an
                            alternate efficiency rating that measures how often a team scores.
                            Sometimes consistency counts more than pure efficiency (points per
                            possession).
                            I didn't include the extra indicators for space reasons, but here
                            are some for a few interesting offenses & defenses (league average
                            floor percentage (Flr%) is 48.2, true shooting percentage (TSP)
                            46.8, free throw ratio (FTR) 22.1, offensive rebound % (Off) 28.7 &
                            turnover percentage (TO%) 16.7):

                            Offense Rating Flr% TSP FTR Off TO%
                            Dallas 108.90 51.6 48.3 20.7 31.3 13.1
                            Sacramento 108.15 51.5 51.2 24.6 27.3 15.1
                            Seattle 104.08 48.0 49.8 19.9 26.7 16.0
                            Minnesota 103.62 50.9 49.1 19.5 26.2 14.1
                            AVERAGE 100.00 48.2 46.8 22.1 28.7 16.7
                            San Antonio 97.25 47.8 46.3 22.0 29.0 16.9
                            Toronto 93.85 45.2 45.3 20.3 24.2 16.7

                            Defense Rating Flr% TSP FTR Off TO%
                            San Antonio 90.70 44.2 42.3 21.0 25.7 17.0
                            Houston 93.51 44.9 42.5 22.7 25.9 15.2
                            Indiana 94.71 46.0 45.5 22.0 26.2 18.2
                            Detroit 95.25 46.0 44.6 18.8 28.0 17.1
                            AVERAGE 100.00 48.2 46.8 22.1 28.7 16.7
                            Dallas 103.88 49.8 49.3 19.8 29.1 15.7
                            Orlando 108.03 51.4 49.2 22.0 31.8 15.5

                            Note that these other indicators are not adjusted for schedule
                            strength.

                            > Sagarin does use home/away in his SOS deduction. He ranks the
                            > Kings' SOS as #24 in the league (Spurs at #17).
                            >
                            I don't use home & away for two reasons: 1) it would be too much
                            work and 2) I intend these rating primarily as whole-season analysis
                            tools, and over a whole season, each team plays a balanced or close
                            to balanced schedule with respect to home and away. The Spurs'
                            schedule rates worse in my system because they have played more road
                            games than home games against the better East teams (this will
                            eventually even out).

                            > In your eXpected Wins column, I guess you are assuming a balanced
                            > schedule for everyone ?
                            >
                            Yes. It's simply the projection based on offensive & defensive
                            ratings, everything else being equal.
                          • ssims22000
                            ... adjusting for ... including ... Just this season s.
                            Message 13 of 18 , Jan 29, 2004
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                              --- In APBR_analysis@yahoogroups.com, igor eduardo küpfer
                              <igorkupfer@r...> wrote:
                              > I may have missed this the first time around, but how are you
                              adjusting for
                              > opponent strength? Just this season's performance, or are you
                              including
                              > previous season(s)?
                              >
                              Just this season's.

                              > ed
                            • Dean Oliver
                              ... time ... the ... Sagarin s stuff is a little bit of overkill for the NBA. Doing simple evaluation of schedule strength and home/road easily accounts for
                              Message 14 of 18 , Jan 31, 2004
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                                --- In APBR_analysis@yahoogroups.com, "Mike G" <msg_53@h...> wrote:
                                > --- In APBR_analysis@yahoogroups.com, "ssims22000" <ssims2@i...>
                                > wrote:
                                > > The team ratings are updated through Jan. 27. I didn't have
                                time
                                > > to include a home/away modifier, so all ratings are calculated
                                the
                                > > same as before.
                                >
                                > I'm curious whether your ratings add anything beyond what Jeff
                                > Sagarin offers:
                                >
                                > http://www.usatoday.com/sports/sagarin/nba0304.htm
                                >
                                > He uses point-differential, rather than off/def efficiencies. It
                                > seems to me a team's scoring differential is going to be equivalent
                                > to their efficiency differential. Whether they are better on
                                > offense or on defense is another matter; but whether team A is
                                > better than team B, does one need that distinction?
                                >

                                Sagarin's stuff is a little bit of overkill for the NBA. Doing
                                simple evaluation of schedule strength and home/road easily accounts
                                for things well enough. Sagarin's evaluation goes above and beyond
                                and makes sense for college where varying schedules are huge.

                                So, yeah, Sagarin's overall evaluation should be roughly comparable.
                                It's just more interesting to look at the offensive and defensive
                                ratings separately. Tells a better story.

                                DeanO
                                www.basketballonpaper.com
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