feat(worldcup): goals forecast (xG + scoreline) + knockout penalties/advance

The card now answers "what's the score, and who goes through?":
- expected goals per side + most likely scoreline, from a fast iterative
  attack/defence Poisson on recent internationals (neutral-aware home advantage;
  a global statsmodels GLM over ~200 nations was too slow for the cron).
- knockout: chance to advance (win in 90'/ET, or win the shootout) + the penalty
  split (shrunk toward a coin-flip — shootouts are near-random).
- fixes an off-by-one date bug (UTC parse rolled fixtures back a day).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: valvesss

site/src/data/wc_live.json

@@ -23,7 +23,14 @@
 "p_draw": 0.252,
 "p_away": 0.192,
 "home_flag": "br",
-"away_flag": "jp"
+"away_flag": "jp",
+"adv_home": 0.7066,
+"adv_away": 0.2934,
+"pen_home": 0.5973,
+"xg_home": 1.82,
+"xg_away": 0.56,
+"score_home": 1,
+"score_away": 0
 },
 "upcoming": [
 {
@@ -43,7 +50,14 @@
 "p_draw": 0.252,
 "p_away": 0.192,
 "home_flag": "br",
-"away_flag": "jp"
+"away_flag": "jp",
+"adv_home": 0.7066,
+"adv_away": 0.2934,
+"pen_home": 0.5973,
+"xg_home": 1.82,
+"xg_away": 0.56,
+"score_home": 1,
+"score_away": 0
 },
 {
 "match_id": "2026-06-29|Germany|Paraguay",
@@ -62,7 +76,14 @@
 "p_draw": 0.2285,
 "p_away": 0.1483,
 "home_flag": "de",
-"away_flag": "py"
+"away_flag": "py",
+"adv_home": 0.7656,
+"adv_away": 0.2344,
+"pen_home": 0.6231,
+"xg_home": 1.48,
+"xg_away": 0.73,
+"score_home": 1,
+"score_away": 0
 },
 {
 "match_id": "2026-06-29|Netherlands|Morocco",
@@ -81,7 +102,14 @@
 "p_draw": 0.2712,
 "p_away": 0.2479,
 "home_flag": "nl",
-"away_flag": "ma"
+"away_flag": "ma",
+"adv_home": 0.6338,
+"adv_away": 0.3662,
+"pen_home": 0.5639,
+"xg_home": 1.0,
+"xg_away": 0.8,
+"score_home": 1,
+"score_away": 0
 },
 {
 "match_id": "2026-06-30|France|Sweden",
@@ -100,7 +128,14 @@
 "p_draw": 0.154,
 "p_away": 0.0683,
 "home_flag": "fr",
-"away_flag": "se"
+"away_flag": "se",
+"adv_home": 0.8805,
+"adv_away": 0.1195,
+"pen_home": 0.6677,
+"xg_home": 1.5,
+"xg_away": 0.74,
+"score_home": 1,
+"score_away": 0
 },
 {
 "match_id": "2026-06-30|Ivory Coast|Norway",
@@ -119,7 +154,14 @@
 "p_draw": 0.2809,
 "p_away": 0.4014,
 "home_flag": "ci",
-"away_flag": "no"
+"away_flag": "no",
+"adv_home": 0.4516,
+"adv_away": 0.5484,
+"pen_home": 0.4767,
+"xg_home": 0.96,
+"xg_away": 1.03,
+"score_home": 0,
+"score_away": 1
 },
 {
 "match_id": "2026-06-30|Mexico|Ecuador",
@@ -138,7 +180,14 @@
 "p_draw": 0.267,
 "p_away": 0.2326,
 "home_flag": "mx",
-"away_flag": "ec"
+"away_flag": "ec",
+"adv_home": 0.6534,
+"adv_away": 0.3466,
+"pen_home": 0.5731,
+"xg_home": 1.51,
+"xg_away": 1.05,
+"score_home": 1,
+"score_away": 1
 },
 {
 "match_id": "2026-07-01|Belgium|Senegal",
@@ -157,7 +206,14 @@
 "p_draw": 0.2535,
 "p_away": 0.1955,
 "home_flag": "be",
-"away_flag": "sn"
+"away_flag": "sn",
+"adv_home": 0.7019,
+"adv_away": 0.2981,
+"pen_home": 0.5953,
+"xg_home": 1.27,
+"xg_away": 0.82,
+"score_home": 1,
+"score_away": 0
 },
 {
 "match_id": "2026-07-01|England|DR Congo",
@@ -176,7 +232,14 @@
 "p_draw": 0.1521,
 "p_away": 0.0669,
 "home_flag": "gb-eng",
-"away_flag": "cd"
+"away_flag": "cd",
+"adv_home": 0.8827,
+"adv_away": 0.1173,
+"pen_home": 0.6685,
+"xg_home": 1.63,
+"xg_away": 0.46,
+"score_home": 1,
+"score_away": 0
 },
 {
 "match_id": "2026-07-01|United States|Bosnia and Herzegovina",
@@ -195,7 +258,14 @@
 "p_draw": 0.1738,
 "p_away": 0.0846,
 "home_flag": "us",
-"away_flag": "ba"
+"away_flag": "ba",
+"adv_home": 0.8561,
+"adv_away": 0.1439,
+"pen_home": 0.659,
+"xg_home": 1.84,
+"xg_away": 0.85,
+"score_home": 1,
+"score_away": 0
 },
 {
 "match_id": "2026-07-02|Portugal|Croatia",
@@ -214,7 +284,14 @@
 "p_draw": 0.2573,
 "p_away": 0.2046,
 "home_flag": "pt",
-"away_flag": "hr"
+"away_flag": "hr",
+"adv_home": 0.6899,
+"adv_away": 0.3101,
+"pen_home": 0.5898,
+"xg_home": 1.28,
+"xg_away": 0.83,
+"score_home": 1,
+"score_away": 0
 },
 {
 "match_id": "2026-07-02|Spain|Austria",
@@ -233,7 +310,14 @@
 "p_draw": 0.1866,
 "p_away": 0.0966,
 "home_flag": "es",
-"away_flag": "at"
+"away_flag": "at",
+"adv_home": 0.8385,
+"adv_away": 0.1615,
+"pen_home": 0.6525,
+"xg_home": 1.63,
+"xg_away": 0.65,
+"score_home": 1,
+"score_away": 0
 },
 {
 "match_id": "2026-07-02|Switzerland|Algeria",
@@ -252,7 +336,14 @@
 "p_draw": 0.2712,
 "p_away": 0.2482,
 "home_flag": "ch",
-"away_flag": "dz"
+"away_flag": "dz",
+"adv_home": 0.6335,
+"adv_away": 0.3665,
+"pen_home": 0.5638,
+"xg_home": 1.33,
+"xg_away": 1.07,
+"score_home": 1,
+"score_away": 1
 },
 {
 "match_id": "2026-07-03|Argentina|Cape Verde",
@@ -271,7 +362,14 @@
 "p_draw": 0.0691,
 "p_away": 0.0205,
 "home_flag": "ar",
-"away_flag": "cv"
+"away_flag": "cv",
+"adv_home": 0.9581,
+"adv_away": 0.0419,
+"pen_home": 0.6912,
+"xg_home": 1.99,
+"xg_away": 0.34,
+"score_home": 1,
+"score_away": 0
 },
 {
 "match_id": "2026-07-03|Australia|Egypt",
@@ -290,7 +388,14 @@
 "p_draw": 0.268,
 "p_away": 0.2362,
 "home_flag": "au",
-"away_flag": "eg"
+"away_flag": "eg",
+"adv_home": 0.6488,
+"adv_away": 0.3512,
+"pen_home": 0.5709,
+"xg_home": 0.79,
+"xg_away": 0.83,
+"score_home": 0,
+"score_away": 0
 },
 {
 "match_id": "2026-07-03|Colombia|Ghana",
@@ -309,7 +414,14 @@
 "p_draw": 0.1139,
 "p_away": 0.042,
 "home_flag": "co",
-"away_flag": "gh"
+"away_flag": "gh",
+"adv_home": 0.9217,
+"adv_away": 0.0783,
+"pen_home": 0.6811,
+"xg_home": 1.67,
+"xg_away": 0.5,
+"score_home": 1,
+"score_away": 0
 }
 ],
 "backtest2026": {

site/src/pages/worldcup.astro

@@ -103,6 +103,23 @@ const pct = (x) => (x * 100).toFixed(0) + '%';
           </div>
         </div>
 
+        <div class="nm-forecast" id="nm-forecast">
+          <div class="nm-fc-card" id="nm-fc-goals">
+            <div class="nm-fc-label">Predicted scoreline</div>
+            <div class="nm-fc-score"><span id="nm-sc-h">–</span><i>:</i><span id="nm-sc-a">–</span></div>
+            <div class="nm-fc-xg">expected goals <b id="nm-xg-h"></b> – <b id="nm-xg-a"></b></div>
+          </div>
+          <div class="nm-fc-card">
+            <div class="nm-fc-label">Knockout — chance to advance</div>
+            <div class="nm-adv-bar"><span class="adv-h" id="nm-adv-h"></span><span class="adv-a" id="nm-adv-a"></span></div>
+            <div class="nm-adv-key">
+              <span><b id="nm-advh"></b> <span id="nm-advhn"></span></span>
+              <span><span id="nm-advan"></span> <b id="nm-adva"></b></span>
+            </div>
+            <div class="nm-pens" id="nm-pens"></div>
+          </div>
+        </div>
+
         <div class="nm-bet">
           <div class="nm-bet-line">Bet on the favourite — <b id="nm-fav"></b></div>
           <div class="nm-verdict" id="nm-verdict"></div>
@@ -312,9 +329,23 @@ python analysis/export_worldcup_data.py   # regenerate this page's data</code></
     $('nm-side-a').classList.toggle('fav', favA);
     setFlag($('nm-flag-h'), f.home_flag, f.home);
     setFlag($('nm-flag-a'), f.away_flag, f.away);
-    $('nm-date').textContent = new Date(f.date).toLocaleDateString('en-GB', { day:'numeric', month:'short', year:'numeric' });
+    $('nm-date').textContent = new Date(f.date + 'T12:00:00').toLocaleDateString('en-GB', { day:'numeric', month:'short', year:'numeric' });
     $('nm-venue').textContent = f.neutral ? 'neutral venue' : `${f.home} hosting`;
 
+    // goals forecast (Poisson) + knockout / penalties
+    const hasG = f.xg_home != null;
+    $('nm-fc-goals').style.display = hasG ? '' : 'none';
+    if (hasG) {
+      $('nm-sc-h').textContent = f.score_home; $('nm-sc-a').textContent = f.score_away;
+      $('nm-xg-h').textContent = f.xg_home.toFixed(2); $('nm-xg-a').textContent = f.xg_away.toFixed(2);
+    }
+    const ah = f.adv_home ?? f.p_fav, aa = f.adv_away ?? (1 - (f.adv_home ?? f.p_fav));
+    $('nm-adv-h').style.width = (ah*100)+'%'; $('nm-adv-a').style.width = (aa*100)+'%';
+    $('nm-advh').textContent = pc(ah); $('nm-advhn').textContent = f.home;
+    $('nm-adva').textContent = pc(aa); $('nm-advan').textContent = f.away;
+    const pen = f.pen_home ?? 0.5;
+    $('nm-pens').innerHTML = `<span>🥅 if it goes to penalties:</span> <b>${f.home} ${pc(pen)}</b> · <b>${f.away} ${pc(1-pen)}</b> <em>— shootouts are near coin-flips</em>`;
+
     // 3-way W/D/L bar
     const ph = f.p_home ?? f.p_fav, pd = f.p_draw ?? 0, pa = f.p_away ?? 0;
     $('nm-wph').textContent = pc(ph);
@@ -423,6 +454,21 @@ python analysis/export_worldcup_data.py   # regenerate this page's data</code></
   .nm-wdl-key b { color: var(--ink); font-family: var(--mono); }
   .nm-wdl-key .dot { display: inline-block; width: 9px; height: 9px; border-radius: 50%; margin-right: 5px; vertical-align: middle; }
   .dot-h { background: var(--accent); } .dot-d { background: var(--ink-faint); } .dot-a { background: var(--navy); }
+  /* goals forecast + knockout */
+  .nm-forecast { display: grid; grid-template-columns: 1fr; gap: 14px; margin-top: 18px; }
+  @media (min-width: 620px) { .nm-forecast { grid-template-columns: 1fr 1.3fr; } }
+  .nm-fc-card { border: 1px solid var(--line-soft); border-radius: 12px; padding: 14px 16px; background: var(--surface); }
+  .nm-fc-label { font-size: .7rem; text-transform: uppercase; letter-spacing: .05em; color: var(--ink-faint); margin-bottom: 8px; }
+  .nm-fc-score { font-family: var(--mono); font-size: 2.2rem; font-weight: 650; color: var(--ink); text-align: center; line-height: 1; }
+  .nm-fc-score i { color: var(--ink-faint); margin: 0 8px; font-style: normal; }
+  .nm-fc-xg { text-align: center; font-size: .8rem; color: var(--ink-faint); margin-top: 6px; }
+  .nm-fc-xg b { color: var(--ink-soft); font-family: var(--mono); }
+  .nm-adv-bar { display: flex; height: 14px; border-radius: 7px; overflow: hidden; background: var(--surface-2); }
+  .nm-adv-bar .adv-h { background: var(--accent); } .nm-adv-bar .adv-a { background: var(--navy); }
+  .nm-adv-key { display: flex; justify-content: space-between; margin-top: 7px; font-size: .82rem; color: var(--ink-soft); }
+  .nm-adv-key b { font-family: var(--mono); color: var(--ink); }
+  .nm-pens { margin-top: 10px; font-size: .82rem; color: var(--ink-soft); text-align: center; }
+  .nm-pens b { color: var(--ink); } .nm-pens em { color: var(--ink-faint); font-size: .76rem; }
   /* the bet */
   .nm-bet { margin-top: 18px; padding-top: 18px; border-top: 1px solid var(--line-soft); }
   .nm-bet-line { text-align: center; font-size: .95rem; color: var(--ink-soft); }

study/analysis/predict_worldcup.py

@@ -43,12 +43,25 @@ def main():
     preds = wc.predict_upcoming(intl, fixtures) if len(fixtures) else fixtures
     asof = fp["date_max"]
 
-    # per-fixture display extras (3-way probs + flags) — cosmetic, keyed by match_id
-    extras = {r.match_id: {
-        "p_home": round(float(r.pH_elo), 4), "p_draw": round(float(r.pD_elo), 4),
-        "p_away": round(float(r.pA_elo), 4),
-        "home_flag": wc.flag_iso(r.HomeTeam), "away_flag": wc.flag_iso(r.AwayTeam),
-    } for r in preds.itertuples()} if len(preds) else {}
+    # per-fixture display extras (3-way probs, flags, goals forecast, penalties)
+    extras = {}
+    gmodel, gteams = wc.fit_intl_goals(intl) if len(preds) else (None, set())
+    for r in (preds.itertuples() if len(preds) else []):
+        pH, pD, pA = float(r.pH_elo), float(r.pD_elo), float(r.pA_elo)
+        cond = pH / (pH + pA) if (pH + pA) > 0 else 0.5
+        s_home = 0.5 + 0.4 * (cond - 0.5)            # shootout win prob (shrunk to ~coin-flip)
+        adv_home = pH + pD * s_home                  # advance: win in 90'/ET, or win the shootout
+        ex = {"p_home": round(pH, 4), "p_draw": round(pD, 4), "p_away": round(pA, 4),
+              "home_flag": wc.flag_iso(r.HomeTeam), "away_flag": wc.flag_iso(r.AwayTeam),
+              "adv_home": round(adv_home, 4), "adv_away": round(1 - adv_home, 4),
+              "pen_home": round(s_home, 4)}
+        g = wc.predict_match_goals(gmodel, gteams, r.HomeTeam, r.AwayTeam, bool(r.neutral))
+        if g:
+            lh, la = g
+            i, j, _ = wc.top_scoreline(lh, la)
+            ex.update({"xg_home": round(float(lh), 2), "xg_away": round(float(la), 2),
+                       "score_home": i, "score_away": j})
+        extras[r.match_id] = ex
 
     # ── append-only ledger: freeze new predictions, reconcile resolved ones ──
     ledger = json.loads(LEDGER.read_text()) if LEDGER.exists() else {"predictions": []}