The Hoop Ledger 2026-27 season
← Forecasts for Oct 30

2026-27 · Regular Season · Final

Chicago Bulls at Boston Celtics

Friday, October 30, 2026 · tip-off 7:30 PM ET

CHI 1–4@BOS 3–1 records going into the game NBA.com recap ↗

Win probability as a share of the court: CHI 20 percent, BOS 80 percent. CHI Bulls 20% proj. 110 · final 111 BOS Celtics · home 80% proj. 122 · final 125
Each team's share of the floor is its pregame win probability. The line starts at midcourt and moves to the split.

Forecast and result

TeamProjectedFinalDifference
CHI Chicago Bulls 110 111 +1
BOS Boston Celtics (home) 122 125 +3

Forecast: Boston Celtics to win, 80% win probability, projected margin 12.

Inside the Forecast

How the inputs are built

Why the model leans BOS

  • Home court+2.1 BOSWhat the model gives the home team on an average night.
  • Team strength+6.2 BOSElo BOS 1608, CHI 1361; season margin BOS +7.5, CHI −8.0.
  • Recent form+3.2 BOSLast 10 games, per 100 possessions: BOS scores 113.8 and allows 111.9; CHI scores 107.6 and allows 117.0.

Together: BOS by 12, a 80% chance. Smaller inputs make up the rest; the chart below has all of them.

Team-by-team notes from the box scores

BOS is 3–1, winning by 8 a game on average (scoring 120, allowing 112). Last season they were a +7 team, which still counts for 80% of their season margin. Their offense shoots 53% eFG against a 55% league average, which alone costs about 2.4 points per 100 possessions. Smaller factors: offensive rebounding +1.3. Their defense holds opponents to 53% eFG against a 55% league average, which alone adds about 2.3 points per 100 possessions. Smaller factors: defensive rebounding +1.4, forcing turnovers −1.0.

CHI is 1–4, losing by 16 a game on average (scoring 114, allowing 130). Last season they were a −5 team, which still counts for 75% of their season margin. Their offense shoots 50% eFG against a 55% league average, which alone costs about 6 points per 100 possessions. Smaller factors: ball security −2.2, getting to the line +1.1. Their defense forces turnovers on 13.3% of opponent possessions (league 12.2%), which alone adds about 1.6 points per 100 possessions. Smaller factors: shooting defense −1.3.

Written from the numbers in Built from the box scores, using only values that rebuild exactly.

How the projected margin was built

Points of home margin. Right of zero favors BOS; left favors CHI.

Projected margin built from a baseline of +2.1 plus Team strength +6.2, Recent form +3.2, Rest and schedule +0.2, No playoff context +0.2, Player availability −0.1, giving +11.9 for BOS. -16-80+8+16 Model baseline +2.1 Team strength +6.2 Recent form +3.2 Rest and schedule +0.2 No playoff context +0.2 Player availability −0.1 Projected margin +11.9
Baseline +2.1 plus the bars equals the projected margin +11.9. The 80% win probability comes from a separate curve on that margin. This shows how the model used its inputs, not what will decide the game. How it's calculated
Every input the model received, with its effect
InputCHIBOSEffect, pts
Elo ratingMargin-of-victory Elo; 1500 is average. 13611608 +0.7
Elo gap, home minus road, incl. home court +317 +4.6
Season scoring marginPoints per game, blended with last season early in the year. −8.0+7.5 +1.9
Games played this season 54 −1.0
Offensive rating, last 10Points scored per 100 possessions. 107.6113.8 +1.1
Defensive rating, last 10Points allowed per 100 possessions; lower is better. 117.0111.9 +1.7
Combined pace, last 10Possessions per game, both teams. 101.7 +0.4
Rotation points missingPoints per game of rotation players listed Out or Doubtful. 0.00.0 −0.1
Rest days 23 +0.2
Second night of a back-to-back NoNo +0.0
All 21 raw inputs, in points for each team
InputValueBOS ptsCHI ptsMargin
Elo gap incl. home court317.3+2.06−2.54+4.59
Season scoring margin (away)-8.0+0.70−0.79+1.49
Offensive rating, last 10 (away)107.6−0.10−1.23+1.13
Rotation points missing (away)0.0−0.40+0.50−0.90
Defensive rating, last 10 (away)117.0+0.97+0.08+0.90
Games played (away)5.0+0.25+1.07−0.82
Defensive rating, last 10 (home)111.9−0.45−1.27+0.82
Rotation points missing (home)0.0+0.62−0.17+0.79
Elo rating (away)1360.9+0.32−0.13+0.46
Combined pace, last 10101.7+3.25+2.87+0.39
Season scoring margin (home)7.5+0.07−0.30+0.37
Elo rating (home)1608.2+0.03−0.24+0.27
Rest days (home)3.0+0.16−0.08+0.24
Home series wins0.0+0.26+0.02+0.24
Games played (home)4.0+0.13+0.28−0.14
Offensive rating, last 10 (home)113.8−0.13−0.10−0.02
Back-to-back (home)0+0.01−0.01+0.02
Rest days (away)2.0+0.00+0.02−0.02
Series pressure0.0+0.02+0.02−0.00
Elimination game0±0.00−0.00+0.00
Back-to-back (away)0±0.00±0.00±0.00
Baseline (average output)114.4112.4+2.10

Built from the box scores

How the breakdowns work

Where each input came from. Open a row to see the games and box-score stats behind it. A breakdown is shown only when rebuilding it from the stored stats gives exactly the number the model received.

Elo ratingCHI1361BOS16085.3 pts toward BOS

Updated after every game from the final score only: wins, losses and margin. Each season starts by keeping 75% of last season's distance from the 1500 average.

CHI1361

1500
  1. Ended last season at 1339 → started this one at 1379
  2. This season's 5 games: −18.1
  • L@TOR92–135−10.0
  • W@MIL132–125+10.7
  • LWAS120–124−10.4
  • L@BOS99–134−5.9
  • LNYK127–133−2.5

BOS1608

1500
  1. Ended last season at 1635 → started this one at 1601
  2. This season's 4 games: +6.9
  • L@DET113–121−6.7
  • WNYK107–103+7.1
  • WCHI134–99+5.9
  • WBKN125–124+0.6
Season scoring marginCHI−8.0BOS+7.50.9 pts toward BOS

Points scored minus points allowed per game this season, mixed with last season's margin until 20 games are played.

CHI−8.0

Scores 114.0, allows 130.2 over 5 games: −16.2 a game.

25% this season (−16.2) + 75% last season (−5.2) = −8.0

BOS+7.5

Scores 119.8, allows 111.8 over 4 games: +8.0 a game.

20% this season (+8.0) + 80% last season (+7.3) = +7.5

Offensive rating, last 10CHI107.6BOS113.81.1 pts toward BOS

Points scored per 100 possessions. Split into the four factors: right of center helps the team, left hurts, in points per 100 possessions compared with the league average (2025-26: 114.6).

CHI107.6scored, −7.0 vs league

FactorCHILeaguehurtshelpsPts
Shooting (eFG%)50.3%54.5%−6.4
Turnovers (TOV%)13.8%12.2%−2.2
Offensive rebounding (OREB%)27.9%26.1%+0.8
Free throws (FTM per FGA)0.2480.210+1.1
Everything else−0.3

BOS113.8scored, −0.8 vs league

FactorBOSLeaguehurtshelpsPts
Shooting (eFG%)52.9%54.5%−2.4
Turnovers (TOV%)11.7%12.2%+0.7
Offensive rebounding (OREB%)29.0%26.1%+1.3
Free throws (FTM per FGA)0.1850.210−0.7
Everything else+0.3
Defensive rating, last 10CHI117.0BOS111.91.7 pts toward BOS

Points allowed per 100 possessions, built from what opponents did in those games. Bars point right when the defense held opponents below average. Split into the four factors: right of center helps the team, left hurts, in points per 100 possessions compared with the league average (2025-26: 114.6).

CHI117.0allowed, +2.4 vs league

FactorOpponentsLeaguehurtshelpsPts
Shooting (eFG%)55.4%54.5%−1.3
Turnovers (TOV%)13.3%12.2%+1.6
Offensive rebounding (OREB%)27.9%26.1%−0.8
Free throws (FTM per FGA)0.2140.210−0.1
Everything else−1.8

BOS111.9allowed, −2.7 vs league

FactorOpponentsLeaguehurtshelpsPts
Shooting (eFG%)53.0%54.5%+2.3
Turnovers (TOV%)11.5%12.2%−1.0
Offensive rebounding (OREB%)22.8%26.1%+1.4
Free throws (FTM per FGA)0.2100.210+0.0
Everything else+0.0
Pace, last 10average 101.70.4 pts toward BOS

Possessions per 48 minutes. The model uses the average of the two teams. Faster games mean more points for both sides, so pace mostly moves the projected total, not the margin.

CHI 107.5 and BOS 95.9 → average 101.7 (league 2025-26: 100.0)

Rotation points missingCHI0.0BOS0.00.1 pts toward CHI

Points per game of rotation players (two or more of the last 10 games this season, 15+ minutes) listed Out or Doubtful on the official injury report.

CHI0.0pts/g missing

Every rotation player was available.

Source: official injury report, 2026-10-30 17:30 ET. 8 rotation players.

BOS0.0pts/g missing

Every rotation player was available.

Source: official injury report, 2026-10-30 17:30 ET. 9 rotation players.

RestCHI2 daysBOS3 days0.2 pts toward BOS

Days since the team's previous game, capped at 5. One day means the second night of a back-to-back.

CHI2days

Last played Oct 28 against NYK.

BOS3days

Last played Oct 27 against BKN.

The last 10 games behind these numbers, box-score totals

CHI

DateOppScoreFG3PFTTOVOREBOffDefPace
Oct 28NYK127–13344-9118-4221-30128122.1127.9104.0
Oct 26@BOS99–13433-8412-4421-31241492.5126.4106.5
Oct 24WAS120–12440-9312-4328-30129113.2118.1105.5
Oct 23@MIL132–12546-9812-4528-301413120.0113.6110.0
Oct 21@TOR92–13527-854-3634-47272182.1122.7111.0
Apr 12@DAL128–14952-10610-3814-191311114.3134.2111.5
Apr 10ORL103–12738-8710-3917-26201095.4118.7107.5
Apr 9@WAS119–10843-939-3024-251513111.2100.9107.0
Apr 7@WAS129–9846-9415-4522-27139119.489.9108.5
Apr 5PHX110–12041-9110-3918-231814105.8117.6103.0

BOS

DateOppScoreFG3PFTTOVOREBOffDefPace
Oct 27BKN125–12442-9311-4130-381411112.6111.7100.5
Oct 26CHI134–9946-9321-4421-292419126.492.5106.5
Oct 23NYK107–10340-8715-3912-161010116.3110.892.5
Oct 20@DET113–12140-8817-4216-211412113.0119.8100.5
May 2PHI100–10937-9313-4913-16510105.3116.094.5
Apr 30@PHI93–10636-8612-419-1613893.0107.199.5
Apr 28PHI97–11336-8911-3914-231215103.2120.294.0
Apr 26@PHI128–9642-8724-5320-281214139.1102.193.0
Apr 24@PHI108–10036-8120-4716-171715121.3112.489.0
Apr 21PHI97–11135-8913-5014-181118107.8126.189.0

Off and Def are points scored and allowed per 100 possessions in each game; their averages are the 10-game ratings above. OREB is missing (–) where the source data didn't record it.

The result against the forecast

2026-27 surprise games
80%
pregame chance the forecast gave BOS, the winner
BOS was the forecast favorite
2 pts
margin miss
forecast +12, actual +14 for BOS
133rd
most surprising result of 2026-27
of 146 graded games so far
125th
largest margin miss of 2026-27
outcome surprise 0.22 nats

Surprise is measured against this model's forecast, not against what other observers expected. Outcome surprise is −ln(winner's pregame probability): 0.69 for a coin flip, 2.3 for a 10% winner.

Team box score

What happened in the game. These numbers are not used by the forecast, and they are not offered as the reason it missed.

Team statCHIBOS
Final score111125
Field goals35–92 · 38.0%42–82 · 51.2%
Three-pointers15–50 · 30.0%10–32 · 31.3%
Free throws26–40 · 65.0%31–40 · 77.5%
Rebounds5141
Assists2428
Turnovers1614
Steals710
Blocks62

How the model does with these teams over time: Chicago Bulls · Boston Celtics

Where the forecast differed from the result

MeasureForecastActualActual − forecast
Home margin (BOS)+12+14+2
Total points232236+4
CHI points110111+1
BOS points122125+3

Recent form before this game

Chicago Bulls

DateOpponentResult
Oct 28 vs NYK L 127–133
Oct 26 at BOS L 99–134
Oct 24 vs WAS L 120–124
Oct 23 at MIL W 132–125
Oct 21 at TOR L 92–135

Boston Celtics

DateOpponentResult
Oct 27 vs BKN W 125–124
Oct 26 vs CHI W 134–99
Oct 23 vs NYK W 107–103
Oct 20 at DET L 113–121
May 2 vs PHI L 100–109

Previous meetings

DateMatchupScore
Oct 26 2026-27 CHI at BOS CHI 99 – 134 BOS
Feb 11 2025-26 CHI at BOS CHI 105 – 124 BOS
Jan 24 2025-26 BOS at CHI BOS 111 – 114 CHI
Jan 5 2025-26 CHI at BOS CHI 101 – 115 BOS
Jan 29 2024-25 CHI at BOS CHI 100 – 122 BOS