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  1. index.html +465 -18
  2. live.html +311 -0
index.html CHANGED
@@ -1,19 +1,466 @@
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- <!doctype html>
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- <html>
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- <head>
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- <meta charset="utf-8" />
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- <meta name="viewport" content="width=device-width" />
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- <title>My static Space</title>
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- <link rel="stylesheet" href="style.css" />
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- </head>
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- <body>
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- <div class="card">
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- <h1>Welcome to your static Space!</h1>
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- <p>You can modify this app directly by editing <i>index.html</i> in the Files and versions tab.</p>
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- <p>
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- Also don't forget to check the
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- <a href="https://huggingface.co/docs/hub/spaces" target="_blank">Spaces documentation</a>.
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- </p>
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- </div>
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- </body>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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  </html>
 
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+ <!DOCTYPE html>
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+ <html lang="en">
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+ <head>
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+ <meta charset="utf-8">
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+ <meta name="viewport" content="width=device-width, initial-scale=1">
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+ <title>Speculative decoding: watch the rejection sampling</title>
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+ <meta name="description" content="Interactive visualization of the acceptance-probability math inside speculative decoding — draft proposes, target verifies, rejects resample from the residual.">
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+ <style>
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+ :root{
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+ color-scheme:light;
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+ --surface:#fcfcfb; --page:#f9f9f7; --ink:#0b0b0b; --ink2:#52514e;
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+ --muted:#898781; --grid:#e1e0d9; --axis:#c3c2b7; --border:rgba(11,11,11,.10);
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+ --target:#2a78d6; --draft:#008300; --residual:#e87ba4;
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+ --accept:#0ca30c; --reject:#d03b3b; --resample:#eb6834; --bonus:#2a78d6;
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+ }
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+ @media (prefers-color-scheme:dark){
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+ :root:not([data-theme="light"]){
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+ color-scheme:dark;
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+ --surface:#1a1a19; --page:#0d0d0d; --ink:#ffffff; --ink2:#c3c2b7;
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+ --muted:#898781; --grid:#2c2c2a; --axis:#383835; --border:rgba(255,255,255,.10);
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+ --target:#3987e5; --draft:#008300; --residual:#d55181;
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+ --accept:#0ca30c; --reject:#d03b3b; --resample:#d95926; --bonus:#3987e5;
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+ }
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+ }
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+ :root[data-theme="dark"]{
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+ color-scheme:dark;
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+ --surface:#1a1a19; --page:#0d0d0d; --ink:#ffffff; --ink2:#c3c2b7;
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+ --muted:#898781; --grid:#2c2c2a; --axis:#383835; --border:rgba(255,255,255,.10);
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+ --target:#3987e5; --draft:#008300; --residual:#d55181;
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+ --accept:#0ca30c; --reject:#d03b3b; --resample:#d95926; --bonus:#3987e5;
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+ }
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+ *{box-sizing:border-box}
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+ body{margin:0;background:var(--page);color:var(--ink);
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+ font-family:system-ui,-apple-system,"Segoe UI",sans-serif;line-height:1.55}
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+ main{max-width:980px;margin:0 auto;padding:24px 16px 80px}
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+ h1{font-size:1.7rem;margin:.2em 0}
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+ h2{font-size:1.2rem;margin:2em 0 .4em}
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+ p{color:var(--ink2);max-width:70ch}
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+ a{color:var(--target)}
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+ code,.mono{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:.92em}
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+ .card{background:var(--surface);border:1px solid var(--border);border-radius:12px;
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+ padding:16px;margin:12px 0}
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+ .row{display:flex;gap:16px;flex-wrap:wrap}
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+ .row>.card{flex:1;min-width:300px;margin:0}
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+ button{background:var(--target);color:#fff;border:0;border-radius:8px;
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+ padding:8px 14px;font:inherit;font-weight:600;cursor:pointer}
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+ button.ghost{background:transparent;color:var(--ink);border:1px solid var(--axis)}
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+ button:disabled{opacity:.5;cursor:default}
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+ select{font:inherit;background:var(--surface);color:var(--ink);
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+ border:1px solid var(--axis);border-radius:8px;padding:6px 8px}
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+ .stat{display:inline-block;margin-right:28px}
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+ .stat b{font-size:1.6rem;font-weight:700}
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+ .stat span{display:block;font-size:.78rem;color:var(--muted)}
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+ .legend{font-size:.82rem;color:var(--ink2);margin:6px 0}
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+ .legend i{display:inline-block;width:10px;height:10px;border-radius:2px;
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+ margin:0 4px 0 14px;vertical-align:baseline}
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+ .chip{display:inline-block;padding:1px 7px;margin:2px;border-radius:4px;color:#fff;
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+ font-family:ui-monospace,Menlo,monospace;font-size:.9em}
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+ #tooltip{position:fixed;pointer-events:none;background:var(--surface);color:var(--ink);
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+ border:1px solid var(--border);border-radius:8px;padding:6px 10px;font-size:.8rem;
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+ box-shadow:0 4px 14px rgba(0,0,0,.15);display:none;z-index:10}
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+ #log{font-size:.9rem;min-height:9em}
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+ #log .step{margin:4px 0;color:var(--ink2)}
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+ #log b{color:var(--ink)}
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+ .hint{font-size:.8rem;color:var(--muted)}
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+ svg text{fill:var(--muted);font-size:11px;font-family:inherit}
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+ svg .val{fill:var(--ink2)}
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+ .topbar{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:8px}
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+ .katex-ish{background:var(--surface);border:1px solid var(--border);border-radius:8px;
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+ padding:10px 14px;font-family:ui-monospace,Menlo,monospace;font-size:.95em;
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+ overflow-x:auto;color:var(--ink)}
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+ </style>
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+ </head>
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+ <body>
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+ <div id="tooltip"></div>
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+ <main>
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+ <div class="topbar">
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+ <div>
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+ <h1>Speculative decoding: watch the rejection sampling</h1>
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+ <p style="margin:.2em 0">Everyone cites the speedup number. Here is the part nobody shows:
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+ the per-token accept/reject math that makes it <em>lossless</em>.</p>
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+ </div>
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+ <div>
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+ <button class="ghost" id="themeBtn" aria-label="toggle theme">◐ theme</button>
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+ <a href="https://github.com/aabhimittal/attention-trace-differ-for-speculative-decoding" style="margin-left:8px">GitHub</a>
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+ <a href="https://huggingface.co/spaces/abhimittal/speculative-decoding-trace" style="margin-left:8px">Live GPU-free Space</a>
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+ </div>
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+ </div>
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+
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+ <h2>1 · The verification step, live</h2>
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+ <p>A cheap <b style="color:var(--draft)">draft model q</b> proposes a token; the expensive
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+ <b style="color:var(--target)">target model p</b> verifies it. Below is one vocabulary
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+ position with toy 8-token distributions. <b>Drag the bars</b> to reshape either
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+ distribution, or pick a preset.</p>
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+
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+ <div class="card">
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+ <div style="display:flex;gap:10px;flex-wrap:wrap;align-items:center">
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+ <select id="preset">
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+ <option value="agree">preset: close agreement</option>
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+ <option value="overconfident">preset: draft overconfident</option>
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+ <option value="disagree">preset: target disagrees</option>
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+ <option value="uniform">preset: uniform draft</option>
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+ </select>
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+ <button id="stepBtn">Propose &amp; verify one token</button>
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+ <button class="ghost" id="runBtn">Run 2,000 trials</button>
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+ <button class="ghost" id="resetBtn">Reset tallies</button>
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+ </div>
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+ <div class="legend">
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+ <i style="background:var(--draft);margin-left:0"></i>draft q (proposes)
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+ <i style="background:var(--target)"></i>target p (verifies)
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+ — drag either series to edit; both stay normalized
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+ </div>
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+ <div id="distChart"></div>
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+ <div style="margin-top:8px">
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+ <span class="stat"><b id="alphaStat">–</b><span>α = Σ min(p,q) · expected acceptance</span></span>
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+ <span class="stat"><b id="tvStat">–</b><span>total variation ½Σ|p−q| = 1−α</span></span>
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+ <span class="stat"><b id="empStat">–</b><span id="empLabel">empirical acceptance (0 trials)</span></span>
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+ </div>
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+ </div>
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+
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+ <div class="row">
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+ <div class="card">
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+ <h2 style="margin:0 0 6px">One verification, step by step</h2>
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+ <div id="log"><div class="step hint">Press “Propose &amp; verify one token”.</div></div>
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+ <div id="residualWrap" style="display:none">
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+ <div class="legend"><i style="background:var(--residual);margin-left:0"></i>
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+ residual norm(max(p−q, 0)) — where rejected tokens are re-drawn from</div>
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+ <div id="residualChart"></div>
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+ </div>
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+ </div>
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+ <div class="card">
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+ <h2 style="margin:0 0 6px">Why it’s lossless</h2>
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+ <p style="font-size:.92rem">Tokens that come out of accept-or-resample are distributed
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+ exactly like the target’s <span class="mono">p</span> — the whole point of the scheme.
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+ Run trials and watch the output histogram converge onto the
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+ <b style="color:var(--target)">p markers</b>.</p>
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+ <div class="legend">
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+ <i style="background:var(--accept);margin-left:0"></i>output via acceptance
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+ <i style="background:var(--resample)"></i>output via resample
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+ <i style="background:var(--target)"></i>target p (goal)
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+ </div>
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+ <div id="outChart"></div>
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+ </div>
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+ </div>
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+
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+ <h2>2 · From acceptance rate to speedup</h2>
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+ <p>With acceptance rate α and γ drafted tokens per round, one target forward pass yields
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+ <span class="mono">E[tokens] = (1 − α<sup>γ+1</sup>) / (1 − α)</span>.
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+ The curve below tracks the α of <em>your</em> distributions above — reshape them and watch
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+ the ceiling move. High α → longer accepted runs → more tokens per expensive call.</p>
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+ <div class="card">
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+ <div id="speedChart"></div>
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+ </div>
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+
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+ <h2>3 · The math, in four lines</h2>
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+ <div class="katex-ish">
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+ 1. draft samples x ~ q(·) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (cheap, autoregressive, γ at a time)<br>
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+ 2. accept x with prob min(1, p(x)/q(x))&nbsp;&nbsp; (target scores all γ in ONE pass)<br>
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+ 3. if rejected: resample x′ ~ norm(max(p − q, 0))<br>
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+ 4. P(output = x) = q(x)·min(1, p(x)/q(x)) + P(reject)·residual(x) = p(x) ✓
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+ </div>
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+ <p>Line 4 is the theorem (Leviathan et al. 2023, <a href="https://arxiv.org/abs/2211.17192">arXiv:2211.17192</a>):
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+ acceptance keeps exactly the probability mass where q overlaps p, and the residual puts back
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+ precisely the mass q under-covered. Nothing is approximated — the output distribution
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+ <em>is</em> the target’s.</p>
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+
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+ <h2>4 · Real models, real traces</h2>
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+ <p>The toy above is exact math on toy distributions. The next step is the same
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+ algorithm on <em>actual model logits</em>: <span class="mono">distilgpt2</span> drafting
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+ for <span class="mono">gpt2</span>, quantized ONNX, executed <b>entirely in your
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+ browser</b> with transformers.js — no server, no GPU quota, no cold start.
172
+ The repo also ships a Gradio app (KV-cached, with attention-trace diffing and an
173
+ optional 70B cloud cross-check) to run locally.</p>
174
+ <div class="card" id="spaceCard">
175
+ <a href="live.html"><button>Run real models in your browser →</button></a>
176
+ <a href="https://huggingface.co/spaces/abhimittal/speculative-decoding-trace" style="margin-left:12px">or open the Hugging Face Space ↗</a>
177
+ </div>
178
+
179
+ <p class="hint" style="margin-top:40px">MIT licensed ·
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+ <a href="https://github.com/aabhimittal/attention-trace-differ-for-speculative-decoding">source</a> ·
181
+ built as a visual artifact for the speculative-decoding verification step.</p>
182
+ </main>
183
+
184
+ <script>
185
+ "use strict";
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+ const VOCAB = ["the","a","cat","dog","sat","ran","fast","."];
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+ const N = VOCAB.length;
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+ const PRESETS = {
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+ agree: {q:[30,22,14,12,9,6,4,3], p:[27,24,15,11,10,6,4,3]},
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+ overconfident:{q:[62,14,8,6,4,3,2,1], p:[28,20,15,12,10,7,5,3]},
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+ disagree: {q:[35,25,15,10,6,4,3,2], p:[4,6,10,14,18,20,16,12]},
192
+ uniform: {q:[1,1,1,1,1,1,1,1], p:[30,20,15,12,9,7,4,3]},
193
+ };
194
+ let qw = PRESETS.agree.q.slice(), pw = PRESETS.agree.p.slice();
195
+ let tally = {n:0, acc:0, outAcc:Array(N).fill(0), outRes:Array(N).fill(0)};
196
+ const $ = id => document.getElementById(id);
197
+ const norm = w => { const s = w.reduce((a,b)=>a+b,0); return w.map(v=>v/s); };
198
+ const fmt = (x,d=3) => x.toFixed(d);
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+
200
+ // ---------- theme ----------
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+ $("themeBtn").onclick = () => {
202
+ const r = document.documentElement;
203
+ const dark = getComputedStyle(document.body).backgroundColor !== "rgb(249, 249, 247)";
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+ r.dataset.theme = dark ? "light" : "dark";
205
+ drawAll();
206
+ };
207
+
208
+ // ---------- tooltip ----------
209
+ const tip = $("tooltip");
210
+ function showTip(e, html){ tip.innerHTML = html; tip.style.display = "block"; moveTip(e); }
211
+ function moveTip(e){ tip.style.left = (e.clientX+14)+"px"; tip.style.top = (e.clientY+10)+"px"; }
212
+ function hideTip(){ tip.style.display = "none"; }
213
+
214
+ // ---------- svg helpers ----------
215
+ const SVGNS = "http://www.w3.org/2000/svg";
216
+ function el(name, attrs, parent){
217
+ const n = document.createElementNS(SVGNS, name);
218
+ for (const k in attrs) n.setAttribute(k, attrs[k]);
219
+ if (parent) parent.appendChild(n);
220
+ return n;
221
+ }
222
+ function cssVar(v){ return getComputedStyle(document.documentElement).getPropertyValue(v).trim(); }
223
+
224
+ // ---------- main editable grouped bar chart ----------
225
+ function drawDist(){
226
+ const q = norm(qw), p = norm(pw);
227
+ const W = Math.min(920, $("distChart").clientWidth || 920), H = 240;
228
+ const padL = 34, padB = 26, padT = 10;
229
+ const plotW = W - padL - 8, plotH = H - padT - padB;
230
+ const ymax = Math.max(...q, ...p, .35);
231
+ const svg = el("svg", {width:"100%", viewBox:`0 0 ${W} ${H}`, role:"img",
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+ "aria-label":"draft and target distributions, drag bars to edit"});
233
+ // gridlines
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+ for (let g = 0; g <= 4; g++){
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+ const y = padT + plotH - plotH * g / 4;
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+ el("line", {x1:padL, x2:W-8, y1:y, y2:y, stroke:cssVar("--grid"), "stroke-width":1}, svg);
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+ el("text", {x:padL-6, y:y+4, "text-anchor":"end"}, svg).textContent = fmt(ymax*g/4,2);
238
+ }
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+ const group = plotW / N, bw = Math.min(34, group/2 - 6);
240
+ const series = [{w:qw, v:q, color:cssVar("--draft"), name:"draft q", off:-bw-1},
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+ {w:pw, v:p, color:cssVar("--target"), name:"target p", off:1}];
242
+ series.forEach((s, si) => {
243
+ s.v.forEach((v, i) => {
244
+ const h = Math.max(2, plotH * v / ymax);
245
+ const x = padL + group*i + group/2 + s.off, y = padT + plotH - h;
246
+ const r = el("rect", {x, y, width:bw, height:h, fill:s.color, rx:4,
247
+ style:"cursor:ns-resize"}, svg);
248
+ const hit = el("rect", {x:x-2, y:padT, width:bw+4, height:plotH,
249
+ fill:"transparent", style:"cursor:ns-resize"}, svg);
250
+ const enter = e => showTip(e, `<b>${VOCAB[i]}</b> · ${s.name} = ${fmt(s.v[i])}`);
251
+ [r,hit].forEach(t => { t.onpointermove = e => { moveTip(e); };
252
+ t.onpointerenter = enter; t.onpointerleave = hideTip; });
253
+ hit.onpointerdown = r.onpointerdown = e => {
254
+ e.preventDefault(); (e.target).setPointerCapture(e.pointerId);
255
+ const drag = ev => {
256
+ const rect = svg.getBoundingClientRect();
257
+ const yy = (ev.clientY - rect.top) * (H / rect.height);
258
+ let frac = (padT + plotH - yy) / plotH;
259
+ frac = Math.max(.005, Math.min(1, frac));
260
+ const others = s.w.reduce((a,b,j)=> j===i ? a : a+b, 0);
261
+ s.w[i] = frac >= .999 ? others*200 : others * frac / (1 - frac);
262
+ drawAll();
263
+ };
264
+ const up = () => { window.removeEventListener("pointermove", drag);
265
+ window.removeEventListener("pointerup", up); };
266
+ window.addEventListener("pointermove", drag);
267
+ window.addEventListener("pointerup", up);
268
+ drag(e);
269
+ };
270
+ });
271
+ });
272
+ VOCAB.forEach((t,i) => el("text", {x:padL+group*i+group/2, y:H-8,
273
+ "text-anchor":"middle"}, svg).textContent = t);
274
+ $("distChart").replaceChildren(svg);
275
+ const alpha = q.reduce((a,_,i)=>a+Math.min(q[i],p[i]),0);
276
+ $("alphaStat").textContent = fmt(alpha);
277
+ $("tvStat").textContent = fmt(1-alpha);
278
+ return {q,p,alpha};
279
+ }
280
+
281
+ // ---------- static bar chart (residual / output) ----------
282
+ function barChart(mount, values, colors, markers, ariaLabel){
283
+ const W = Math.min(440, mount.clientWidth || 440), H = 170;
284
+ const padL = 30, padB = 24, padT = 8;
285
+ const plotW = W - padL - 8, plotH = H - padT - padB;
286
+ const ymax = Math.max(...values.map((v,i)=>v), ...(markers||[0]), .3);
287
+ const svg = el("svg", {width:"100%", viewBox:`0 0 ${W} ${H}`, role:"img", "aria-label":ariaLabel});
288
+ for (let g = 0; g <= 2; g++){
289
+ const y = padT + plotH - plotH*g/2;
290
+ el("line",{x1:padL,x2:W-8,y1:y,y2:y,stroke:cssVar("--grid")},svg);
291
+ el("text",{x:padL-5,y:y+4,"text-anchor":"end"},svg).textContent = fmt(ymax*g/2,2);
292
+ }
293
+ const group = plotW / N, bw = Math.min(26, group-10);
294
+ values.forEach((v,i)=>{
295
+ const h = Math.max(v>0?2:0, plotH*v/ymax);
296
+ const x = padL + group*i + (group-bw)/2, y = padT + plotH - h;
297
+ const r = el("rect",{x,y,width:bw,height:h,fill:colors[i],rx:4},svg);
298
+ r.onpointerenter = e => showTip(e, `<b>${VOCAB[i]}</b> · ${fmt(v)}`);
299
+ r.onpointermove = moveTip; r.onpointerleave = hideTip;
300
+ if (markers){
301
+ const my = padT + plotH - plotH*markers[i]/ymax;
302
+ el("line",{x1:x-3,x2:x+bw+3,y1:my,y2:my,stroke:cssVar("--target"),
303
+ "stroke-width":2.5},svg);
304
+ }
305
+ el("text",{x:padL+group*i+group/2,y:H-6,"text-anchor":"middle"},svg).textContent = VOCAB[i];
306
+ });
307
+ mount.replaceChildren(svg);
308
+ }
309
+
310
+ // ---------- speedup curve ----------
311
+ function drawSpeed(alpha){
312
+ const W = Math.min(920, $("speedChart").clientWidth || 920), H = 210;
313
+ const padL = 38, padB = 28, padT = 12;
314
+ const plotW = W - padL - 16, plotH = H - padT - padB;
315
+ const gmax = 8;
316
+ const E = g => alpha >= .9999 ? g+1 : (1 - Math.pow(alpha, g+1)) / (1 - alpha);
317
+ const ymax = Math.max(E(gmax), 2);
318
+ const svg = el("svg",{width:"100%",viewBox:`0 0 ${W} ${H}`,role:"img",
319
+ "aria-label":"expected tokens per target call vs gamma"});
320
+ for (let g = 0; g <= 4; g++){
321
+ const y = padT + plotH - plotH*g/4;
322
+ el("line",{x1:padL,x2:padL+plotW,y1:y,y2:y,stroke:cssVar("--grid")},svg);
323
+ el("text",{x:padL-6,y:y+4,"text-anchor":"end"},svg).textContent = fmt(ymax*g/4,1);
324
+ }
325
+ const X = g => padL + plotW*(g-1)/(gmax-1), Y = v => padT + plotH - plotH*v/ymax;
326
+ let d = "";
327
+ for (let g = 1; g <= gmax; g++) d += (g===1?"M":"L") + X(g) + " " + Y(E(g)) + " ";
328
+ el("path",{d,fill:"none",stroke:cssVar("--target"),"stroke-width":2},svg);
329
+ el("line",{x1:padL,x2:padL+plotW,y1:Y(1),y2:Y(1),stroke:cssVar("--axis"),
330
+ "stroke-dasharray":"4 4"},svg);
331
+ el("text",{x:padL+plotW,y:Y(1)-6,"text-anchor":"end"},svg).textContent = "plain autoregressive (1×)";
332
+ for (let g = 1; g <= gmax; g++){
333
+ const c = el("circle",{cx:X(g),cy:Y(E(g)),r:5,fill:cssVar("--target"),
334
+ stroke:cssVar("--surface"),"stroke-width":2},svg);
335
+ c.onpointerenter = e => showTip(e,
336
+ `γ=${g} → <b>${fmt(E(g),2)}</b> tokens per target call<br>at α=${fmt(alpha,2)}`);
337
+ c.onpointermove = moveTip; c.onpointerleave = hideTip;
338
+ el("text",{x:X(g),y:H-8,"text-anchor":"middle"},svg).textContent = "γ="+g;
339
+ }
340
+ const lbl = el("text",{x:padL+10,y:padT+14,class:"val"},svg);
341
+ lbl.textContent = `α=${fmt(alpha,2)} → ${fmt(E(gmax),2)} tokens/call at γ=8`;
342
+ $("speedChart").replaceChildren(svg);
343
+ }
344
+
345
+ // ---------- output histogram ----------
346
+ function drawOut(p){
347
+ const n = Math.max(tally.n, 1);
348
+ const stackTotals = tally.outAcc.map((a,i)=>(a+tally.outRes[i])/n);
349
+ // draw as stacked: accepted portion + resampled portion
350
+ const mount = $("outChart");
351
+ const W = Math.min(440, mount.clientWidth || 440), H = 190;
352
+ const padL = 30, padB = 24, padT = 8;
353
+ const plotW = W - padL - 8, plotH = H - padT - padB;
354
+ const ymax = Math.max(...stackTotals, ...p, .3);
355
+ const svg = el("svg",{width:"100%",viewBox:`0 0 ${W} ${H}`,role:"img",
356
+ "aria-label":"empirical output distribution vs target p"});
357
+ for (let g = 0; g <= 2; g++){
358
+ const y = padT + plotH - plotH*g/2;
359
+ el("line",{x1:padL,x2:W-8,y1:y,y2:y,stroke:cssVar("--grid")},svg);
360
+ el("text",{x:padL-5,y:y+4,"text-anchor":"end"},svg).textContent = fmt(ymax*g/2,2);
361
+ }
362
+ const group = plotW / N, bw = Math.min(26, group-10);
363
+ for (let i = 0; i < N; i++){
364
+ const x = padL + group*i + (group-bw)/2;
365
+ const hA = plotH * (tally.outAcc[i]/n) / ymax;
366
+ const hR = plotH * (tally.outRes[i]/n) / ymax;
367
+ const yA = padT + plotH - hA;
368
+ if (hA > 0) el("rect",{x,y:yA,width:bw,height:Math.max(hA,1),fill:cssVar("--accept"),rx:2},svg);
369
+ if (hR > 0) el("rect",{x,y:yA-hR-2,width:bw,height:Math.max(hR,1),
370
+ fill:cssVar("--resample"),rx:2},svg);
371
+ const my = padT + plotH - plotH*p[i]/ymax;
372
+ el("line",{x1:x-3,x2:x+bw+3,y1:my,y2:my,stroke:cssVar("--target"),"stroke-width":2.5},svg);
373
+ const hit = el("rect",{x:x-2,y:padT,width:bw+4,height:plotH,fill:"transparent"},svg);
374
+ hit.onpointerenter = e => showTip(e, `<b>${VOCAB[i]}</b><br>` +
375
+ `empirical: ${fmt(stackTotals[i])} (acc ${fmt(tally.outAcc[i]/n)}, ` +
376
+ `resampled ${fmt(tally.outRes[i]/n)})<br>target p: ${fmt(p[i])}`);
377
+ hit.onpointermove = moveTip; hit.onpointerleave = hideTip;
378
+ el("text",{x:padL+group*i+group/2,y:H-6,"text-anchor":"middle"},svg).textContent = VOCAB[i];
379
+ }
380
+ mount.replaceChildren(svg);
381
+ }
382
+
383
+ // ---------- the actual rejection sampling ----------
384
+ function sample(dist){
385
+ let u = Math.random(), c = 0;
386
+ for (let i = 0; i < dist.length; i++){ c += dist[i]; if (u < c) return i; }
387
+ return dist.length - 1;
388
+ }
389
+ function residualOf(p, q){
390
+ const r = p.map((v,i)=>Math.max(v - q[i], 0));
391
+ const s = r.reduce((a,b)=>a+b,0);
392
+ return s > 0 ? r.map(v=>v/s) : p.slice();
393
+ }
394
+ function verifyOnce(q, p){
395
+ const x = sample(q);
396
+ const ratio = p[x] / q[x];
397
+ const aProb = Math.min(1, ratio);
398
+ const u = Math.random();
399
+ const accepted = u < aProb;
400
+ let out = x, res = null;
401
+ if (!accepted){ res = residualOf(p, q); out = sample(res); }
402
+ return {x, ratio, aProb, u, accepted, out, res};
403
+ }
404
+
405
+ function stepOnce(){
406
+ const {q, p} = drawDist();
407
+ const t = verifyOnce(q, p);
408
+ tally.n++; if (t.accepted){ tally.acc++; tally.outAcc[t.out]++; } else tally.outRes[t.out]++;
409
+ const log = $("log"); log.replaceChildren();
410
+ const add = h => { const d = document.createElement("div"); d.className = "step";
411
+ d.innerHTML = h; log.appendChild(d); };
412
+ add(`1 · draft samples x ~ q → <span class="chip" style="background:var(--draft)">${VOCAB[t.x]}</span> (q=${fmt(q[t.x])})`);
413
+ add(`2 · target scores it: p(<b>${VOCAB[t.x]}</b>) = <b>${fmt(p[t.x])}</b> → ratio p/q = <b>${fmt(t.ratio,2)}</b>`);
414
+ add(`3 · accept prob = min(1, ${fmt(t.ratio,2)}) = <b>${fmt(t.aProb)}</b>; uniform draw u = <b>${fmt(t.u)}</b>`);
415
+ if (t.accepted){
416
+ add(`4 · u &lt; ${fmt(t.aProb)} → <b style="color:var(--accept)">✓ ACCEPTED</b> — output <span class="chip" style="background:var(--accept)">${VOCAB[t.out]}</span>`);
417
+ $("residualWrap").style.display = "none";
418
+ } else {
419
+ add(`4 · u ≥ ${fmt(t.aProb)} → <b style="color:var(--reject)">✗ REJECTED</b> — the draft over-claimed this token`);
420
+ add(`5 · resample from norm(max(p−q,0)) → <span class="chip" style="background:var(--resample)">${VOCAB[t.out]}</span>`);
421
+ $("residualWrap").style.display = "block";
422
+ barChart($("residualChart"), t.res, VOCAB.map(()=>cssVar("--residual")), null,
423
+ "residual distribution");
424
+ }
425
+ refreshStats(p);
426
+ }
427
+
428
+ function runMany(){
429
+ const {q, p} = drawDist();
430
+ for (let k = 0; k < 2000; k++){
431
+ const t = verifyOnce(q, p);
432
+ tally.n++; if (t.accepted){ tally.acc++; tally.outAcc[t.out]++; } else tally.outRes[t.out]++;
433
+ }
434
+ refreshStats(p);
435
+ }
436
+
437
+ function refreshStats(p){
438
+ $("empStat").textContent = tally.n ? fmt(tally.acc/tally.n) : "–";
439
+ $("empLabel").textContent = `empirical acceptance (${tally.n.toLocaleString()} trials)`;
440
+ drawOut(p);
441
+ }
442
+
443
+ function drawAll(){
444
+ const {q, p, alpha} = drawDist();
445
+ drawSpeed(alpha);
446
+ drawOut(p);
447
+ }
448
+
449
+ $("preset").onchange = e => {
450
+ const pr = PRESETS[e.target.value];
451
+ qw = pr.q.slice(); pw = pr.p.slice();
452
+ $("resetBtn").click();
453
+ };
454
+ $("stepBtn").onclick = stepOnce;
455
+ $("runBtn").onclick = runMany;
456
+ $("resetBtn").onclick = () => {
457
+ tally = {n:0, acc:0, outAcc:Array(N).fill(0), outRes:Array(N).fill(0)};
458
+ $("log").innerHTML = '<div class="step hint">Press “Propose &amp; verify one token”.</div>';
459
+ $("residualWrap").style.display = "none";
460
+ drawAll(); refreshStats(norm(pw));
461
+ };
462
+ window.addEventListener("resize", drawAll);
463
+ drawAll();
464
+ </script>
465
+ </body>
466
  </html>
live.html ADDED
@@ -0,0 +1,311 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ <!DOCTYPE html>
2
+ <html lang="en">
3
+ <head>
4
+ <meta charset="utf-8">
5
+ <meta name="viewport" content="width=device-width, initial-scale=1">
6
+ <title>Real speculative decoding, in your browser</title>
7
+ <meta name="description" content="distilgpt2 drafts, gpt2 verifies — real rejection sampling with per-token acceptance math, running fully client-side via transformers.js.">
8
+ <style>
9
+ :root{
10
+ color-scheme:light;
11
+ --surface:#fcfcfb; --page:#f9f9f7; --ink:#0b0b0b; --ink2:#52514e;
12
+ --muted:#898781; --grid:#e1e0d9; --axis:#c3c2b7; --border:rgba(11,11,11,.10);
13
+ --target:#2a78d6; --draft:#008300; --residual:#e87ba4;
14
+ --accept:#0ca30c; --reject:#d03b3b; --resample:#eb6834; --bonus:#2a78d6;
15
+ }
16
+ @media (prefers-color-scheme:dark){
17
+ :root:not([data-theme="light"]){
18
+ color-scheme:dark;
19
+ --surface:#1a1a19; --page:#0d0d0d; --ink:#ffffff; --ink2:#c3c2b7;
20
+ --muted:#898781; --grid:#2c2c2a; --axis:#383835; --border:rgba(255,255,255,.10);
21
+ --target:#3987e5; --draft:#008300; --residual:#d55181;
22
+ --accept:#0ca30c; --reject:#d03b3b; --resample:#d95926; --bonus:#3987e5;
23
+ }
24
+ }
25
+ :root[data-theme="dark"]{
26
+ color-scheme:dark;
27
+ --surface:#1a1a19; --page:#0d0d0d; --ink:#ffffff; --ink2:#c3c2b7;
28
+ --muted:#898781; --grid:#2c2c2a; --axis:#383835; --border:rgba(255,255,255,.10);
29
+ --target:#3987e5; --draft:#008300; --residual:#d55181;
30
+ --accept:#0ca30c; --reject:#d03b3b; --resample:#d95926; --bonus:#3987e5;
31
+ }
32
+ *{box-sizing:border-box}
33
+ body{margin:0;background:var(--page);color:var(--ink);
34
+ font-family:system-ui,-apple-system,"Segoe UI",sans-serif;line-height:1.55}
35
+ main{max-width:980px;margin:0 auto;padding:24px 16px 80px}
36
+ h1{font-size:1.6rem;margin:.2em 0}
37
+ p{color:var(--ink2);max-width:75ch}
38
+ a{color:var(--target)}
39
+ code{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:.92em}
40
+ .card{background:var(--surface);border:1px solid var(--border);border-radius:12px;
41
+ padding:16px;margin:12px 0}
42
+ button{background:var(--target);color:#fff;border:0;border-radius:8px;
43
+ padding:8px 14px;font:inherit;font-weight:600;cursor:pointer}
44
+ button:disabled{opacity:.5;cursor:default}
45
+ input[type=text],select{font:inherit;background:var(--surface);color:var(--ink);
46
+ border:1px solid var(--axis);border-radius:8px;padding:6px 8px}
47
+ input[type=range]{accent-color:var(--target)}
48
+ label{font-size:.82rem;color:var(--ink2)}
49
+ .stat{display:inline-block;margin-right:26px}
50
+ .stat b{font-size:1.5rem;font-weight:700}
51
+ .stat span{display:block;font-size:.76rem;color:var(--muted)}
52
+ .chip{display:inline-block;padding:2px 6px;margin:2px;border-radius:4px;color:#fff;
53
+ font-family:ui-monospace,Menlo,monospace;font-size:.9em}
54
+ .legend{font-size:.82rem;color:var(--ink2);margin:6px 0}
55
+ .legend i{display:inline-block;width:10px;height:10px;border-radius:2px;
56
+ margin:0 4px 0 14px;vertical-align:baseline}
57
+ .poscard{border:1px solid var(--grid);border-radius:8px;padding:10px 12px;margin:8px 0}
58
+ .poscard .meta{color:var(--muted);font-size:12px}
59
+ .bars{display:flex;gap:16px;flex-wrap:wrap;margin-top:8px}
60
+ .bars>div{flex:1;min-width:230px}
61
+ .brow{display:flex;align-items:center;gap:6px;margin:2px 0}
62
+ .brow code{width:92px;text-align:right;overflow:hidden;color:var(--ink2)}
63
+ .btrack{flex:1;background:var(--grid);border-radius:4px;height:13px}
64
+ .bfill{height:13px;border-radius:4px}
65
+ .brow span{width:52px;color:var(--ink2);font-size:12px}
66
+ #status{font-size:.85rem;color:var(--muted)}
67
+ progress{width:220px;vertical-align:middle}
68
+ .warn{color:var(--resample);font-size:.85rem}
69
+ </style>
70
+ </head>
71
+ <body>
72
+ <main>
73
+ <h1>Real speculative decoding — running in your browser</h1>
74
+ <p><b style="color:var(--draft)">distilgpt2</b> drafts γ tokens, <b style="color:var(--target)">gpt2</b>
75
+ verifies them — quantized ONNX models executed client-side with
76
+ <a href="https://huggingface.co/docs/transformers.js">transformers.js</a>
77
+ (WebGPU when available, WASM otherwise). No server, no GPU quota, no cold start:
78
+ the rejection sampling below is the actual algorithm on actual model logits.
79
+ <a href="index.html">← back to the interactive explainer</a></p>
80
+
81
+ <div class="card">
82
+ <button id="loadBtn">Load models (~70 MB, cached after first visit)</button>
83
+ <span id="status"></span>
84
+ <div id="loadWarn" class="warn"></div>
85
+ </div>
86
+
87
+ <div class="card" id="controls" style="display:none">
88
+ <div style="display:flex;gap:12px;flex-wrap:wrap;align-items:end">
89
+ <div style="flex:2;min-width:260px"><label>Prompt</label><br>
90
+ <input type="text" id="prompt" style="width:100%"
91
+ value="The key idea behind speculative decoding is"></div>
92
+ <div><label>γ = <span id="gammaV">4</span></label><br>
93
+ <input type="range" id="gamma" min="1" max="8" step="1" value="4"></div>
94
+ <div><label>temperature = <span id="tempV">0.8</span></label><br>
95
+ <input type="range" id="temp" min="0" max="1.5" step="0.1" value="0.8"></div>
96
+ <div><label>max new = <span id="maxV">24</span></label><br>
97
+ <input type="range" id="maxNew" min="8" max="48" step="4" value="24"></div>
98
+ <div><label>seed</label><br>
99
+ <input type="text" id="seed" value="0" style="width:64px"></div>
100
+ <div><button id="runBtn">Run</button></div>
101
+ </div>
102
+ </div>
103
+
104
+ <div class="card" id="results" style="display:none">
105
+ <div id="stats"></div>
106
+ <div class="legend">
107
+ <i style="background:var(--accept);margin-left:0"></i>accepted
108
+ <i style="background:var(--reject)"></i>rejected
109
+ <i style="background:var(--resample)"></i>resampled
110
+ <i style="background:var(--bonus)"></i>bonus
111
+ </div>
112
+ <div id="ribbon" style="line-height:2"></div>
113
+ <h3 style="margin:14px 0 4px">Per-position acceptance math</h3>
114
+ <div id="cards"></div>
115
+ </div>
116
+
117
+ <p class="hint" style="font-size:.8rem;color:var(--muted)">
118
+ Everything stays on your device — the models are fetched from the Hugging Face
119
+ CDN and executed locally. Source:
120
+ <a href="https://github.com/aabhimittal/attention-trace-differ-for-speculative-decoding">GitHub</a>.
121
+ The repo also ships a Gradio app (with KV caching, attention-trace diffing and
122
+ a 70B cloud cross-check) you can run locally with <code>python app.py</code>.</p>
123
+ </main>
124
+
125
+ <script type="module">
126
+ import { AutoTokenizer, AutoModelForCausalLM, Tensor }
127
+ from "https://cdn.jsdelivr.net/npm/@huggingface/transformers@3.5.2";
128
+
129
+ const $ = id => document.getElementById(id);
130
+ const esc = s => s.replace(/&/g,"&amp;").replace(/</g,"&lt;").replace(/>/g,"&gt;");
131
+ const vis = t => t.trim() === "" ? t.replace(/ /g,"·") || "·" : t;
132
+ ["gamma","temp","maxNew"].forEach((id,i) =>
133
+ $(id).oninput = () => $(["gammaV","tempV","maxV"][i]).textContent = $(id).value);
134
+
135
+ let tok, draft, target, VOCAB;
136
+
137
+ // mulberry32 — seedable RNG so runs are reproducible
138
+ function rng(seed){ let a = seed >>> 0;
139
+ return () => { a |= 0; a = a + 0x6D2B79F5 | 0;
140
+ let t = Math.imul(a ^ a >>> 15, 1 | a);
141
+ t = t + Math.imul(t ^ t >>> 7, 61 | t) ^ t;
142
+ return ((t ^ t >>> 14) >>> 0) / 4294967296; }; }
143
+
144
+ function softmax(row, temperature){
145
+ const n = row.length, out = new Float32Array(n);
146
+ if (temperature <= 0){ // greedy: one-hot argmax
147
+ let mi = 0; for (let i = 1; i < n; i++) if (row[i] > row[mi]) mi = i;
148
+ out[mi] = 1; return out; }
149
+ let mx = -Infinity;
150
+ for (let i = 0; i < n; i++){ const v = row[i]/temperature; out[i] = v; if (v > mx) mx = v; }
151
+ let s = 0;
152
+ for (let i = 0; i < n; i++){ out[i] = Math.exp(out[i]-mx); s += out[i]; }
153
+ for (let i = 0; i < n; i++) out[i] /= s;
154
+ return out;
155
+ }
156
+ function sampleFrom(p, r){
157
+ let u = r(), c = 0;
158
+ for (let i = 0; i < p.length; i++){ c += p[i]; if (u < c) return i; }
159
+ return p.length - 1;
160
+ }
161
+ function top8(p){
162
+ const idx = [];
163
+ for (let i = 0; i < p.length; i++){
164
+ if (idx.length < 8){ idx.push(i); idx.sort((a,b)=>p[b]-p[a]); }
165
+ else if (p[i] > p[idx[7]]){ idx[7] = i; idx.sort((a,b)=>p[b]-p[a]); } }
166
+ return idx.map(i => ({ id: i, prob: p[i] }));
167
+ }
168
+ async function forward(model, ids){
169
+ const t = new Tensor("int64", BigInt64Array.from(ids.map(BigInt)), [1, ids.length]);
170
+ const mask = new Tensor("int64", BigInt64Array.from(ids.map(()=>1n)), [1, ids.length]);
171
+ const out = await model({ input_ids: t, attention_mask: mask });
172
+ return out.logits; // [1, seq, vocab]
173
+ }
174
+ const rowOf = (logits, r) =>
175
+ logits.data.subarray(r * VOCAB, (r + 1) * VOCAB);
176
+
177
+ $("loadBtn").onclick = async () => {
178
+ $("loadBtn").disabled = true;
179
+ const status = p => $("status").textContent = p;
180
+ const progress = d => { if (d.status === "progress" && d.file?.endsWith(".onnx"))
181
+ status(`${d.file.split("/").pop()} ${Math.round(d.progress||0)}%`); };
182
+ let device = "wasm";
183
+ try { if (navigator.gpu && await navigator.gpu.requestAdapter()) device = "webgpu"; }
184
+ catch { /* wasm fallback */ }
185
+ try {
186
+ status("loading tokenizer…");
187
+ tok = await AutoTokenizer.from_pretrained("Xenova/distilgpt2");
188
+ status("loading draft (distilgpt2)…");
189
+ draft = await AutoModelForCausalLM.from_pretrained("Xenova/distilgpt2",
190
+ { dtype: "q8", device, progress_callback: progress });
191
+ status("loading target (gpt2)…");
192
+ target = await AutoModelForCausalLM.from_pretrained("Xenova/gpt2",
193
+ { dtype: "q8", device, progress_callback: progress });
194
+ } catch (e) {
195
+ if (device === "webgpu"){ // some GPUs fail on q8 — retry on wasm
196
+ $("loadWarn").textContent = "WebGPU load failed, retrying on WASM…";
197
+ device = "wasm";
198
+ draft = await AutoModelForCausalLM.from_pretrained("Xenova/distilgpt2",
199
+ { dtype: "q8", device, progress_callback: progress });
200
+ target = await AutoModelForCausalLM.from_pretrained("Xenova/gpt2",
201
+ { dtype: "q8", device, progress_callback: progress });
202
+ } else { status("load failed: " + e.message); $("loadBtn").disabled = false; return; }
203
+ }
204
+ status(`ready · running on ${device}`);
205
+ $("controls").style.display = "block";
206
+ };
207
+
208
+ function bars(top, cls, hlId){
209
+ return top.map(({id, prob}) =>
210
+ `<div class="brow"><code style="${id===hlId?'font-weight:700':''}">${esc(vis(tok.decode([id])))}</code>` +
211
+ `<div class="btrack"><div class="bfill" style="width:${Math.max(prob*100,.5).toFixed(1)}%;` +
212
+ `background:var(--${cls})"></div></div><span>${prob.toFixed(3)}</span></div>`).join("");
213
+ }
214
+
215
+ $("runBtn").onclick = async () => {
216
+ $("runBtn").disabled = true;
217
+ $("results").style.display = "block";
218
+ $("stats").innerHTML = ""; $("ribbon").innerHTML = ""; $("cards").innerHTML = "";
219
+ const gamma = +$("gamma").value, temp = +$("temp").value,
220
+ maxNew = +$("maxNew").value, r = rng(+$("seed").value || 0);
221
+ const enc = await tok($("prompt").value);
222
+ let ids = Array.from(enc.input_ids.data, Number);
223
+ const promptLen = ids.length;
224
+ VOCAB = null;
225
+ let proposed = 0, acceptedN = 0, rounds = 0, t0 = performance.now();
226
+ const chip = (txt, color, extra="") =>
227
+ `<span class="chip" style="background:var(--${color});${extra}" >${esc(vis(txt))}</span>`;
228
+
229
+ while (ids.length - promptLen < maxNew) {
230
+ rounds++;
231
+ const roundStart = ids.length;
232
+ // draft proposes gamma tokens (no KV cache in-browser; seqs stay short)
233
+ let draftIds = ids.slice(); const qDists = [];
234
+ for (let k = 0; k < gamma; k++){
235
+ const logits = await forward(draft, draftIds);
236
+ VOCAB ??= logits.dims[2];
237
+ const q = softmax(rowOf(logits, draftIds.length - 1), temp);
238
+ qDists.push(q);
239
+ draftIds.push(sampleFrom(q, r));
240
+ $("status").textContent = `round ${rounds}: drafting ${k+1}/${gamma}…`;
241
+ }
242
+ // target verifies all positions in one forward pass
243
+ $("status").textContent = `round ${rounds}: target verifying…`;
244
+ const tLogits = await forward(target, draftIds);
245
+ const pDist = s => softmax(rowOf(tLogits, ids.length - 1 + s), temp);
246
+
247
+ const props = draftIds.slice(ids.length);
248
+ let rejected = false;
249
+ for (let i = 0; i < props.length; i++){
250
+ const x = props[i], q = qDists[i], p = pDist(i);
251
+ const qx = q[x], px = p[x];
252
+ const ratio = qx > 0 ? px / qx : Infinity;
253
+ const aProb = Math.min(1, ratio);
254
+ const u = r();
255
+ const ok = u < aProb;
256
+ proposed++;
257
+ const tokStr = tok.decode([x]);
258
+ let cardTail = "", ribbonAdd = "";
259
+ if (ok){
260
+ acceptedN++;
261
+ ribbonAdd = chip(tokStr, "accept");
262
+ } else {
263
+ // resample from the residual norm(max(p − q, 0))
264
+ const res = new Float32Array(VOCAB); let s = 0;
265
+ for (let j = 0; j < VOCAB; j++){ const v = Math.max(p[j]-q[j], 0); res[j] = v; s += v; }
266
+ let newTok;
267
+ if (s > 0){ for (let j = 0; j < VOCAB; j++) res[j] /= s; newTok = sampleFrom(res, r); }
268
+ else newTok = sampleFrom(p, r);
269
+ const newStr = tok.decode([newTok]);
270
+ ribbonAdd = chip(tokStr, "reject", "opacity:.55;text-decoration:line-through")
271
+ + chip(newStr, "resample");
272
+ cardTail = `<div class="bars"><div>
273
+ <div class="meta">residual norm(max(p−q,0))</div>${bars(top8(res), "residual", newTok)}</div></div>`;
274
+ ids = ids.concat(props.slice(0, i), [newTok]);
275
+ rejected = true;
276
+ }
277
+ $("ribbon").insertAdjacentHTML("beforeend", ribbonAdd);
278
+ $("cards").insertAdjacentHTML("beforeend",
279
+ `<div class="poscard">
280
+ <div class="meta">position ${roundStart - promptLen + i} — draft proposed <code>${esc(vis(tokStr))}</code></div>
281
+ <div>q(x)=<b>${qx.toFixed(4)}</b> · p(x)=<b>${px.toFixed(4)}</b> ·
282
+ p/q=<b>${ratio === Infinity ? "∞" : ratio.toFixed(3)}</b> ·
283
+ accept prob=<b>${aProb.toFixed(3)}</b> · u=<b>${u.toFixed(3)}</b> →
284
+ <b style="color:var(--${ok ? "accept" : "reject"})">${ok ? "✓ ACCEPTED" : "✗ REJECTED"}</b></div>
285
+ <div class="bars">
286
+ <div><div class="meta">draft q — top 8</div>${bars(top8(q), "draft", x)}</div>
287
+ <div><div class="meta">target p — top 8</div>${bars(top8(p), "target", x)}</div>
288
+ </div>${cardTail}</div>`);
289
+ if (!ok) break;
290
+ }
291
+ if (!rejected){
292
+ const pb = pDist(gamma);
293
+ const bonus = sampleFrom(pb, r);
294
+ ids = ids.concat(props, [bonus]);
295
+ $("ribbon").insertAdjacentHTML("beforeend", chip(tok.decode([bonus]), "bonus"));
296
+ }
297
+ const dt = (performance.now() - t0) / 1000;
298
+ const gen = ids.length - promptLen;
299
+ $("stats").innerHTML =
300
+ `<span class="stat"><b>${proposed ? Math.round(100*acceptedN/proposed) : 0}%</b><span>acceptance rate</span></span>` +
301
+ `<span class="stat"><b>${acceptedN}/${proposed}</b><span>draft tokens accepted</span></span>` +
302
+ `<span class="stat"><b>${(gen/rounds).toFixed(2)}×</b><span>tokens per target forward pass</span></span>` +
303
+ `<span class="stat"><b>${rounds}</b><span>target calls (vs ${gen} autoregressive)</span></span>` +
304
+ `<span class="stat"><b>${(gen/dt).toFixed(1)}</b><span>tokens/s in-browser</span></span>`;
305
+ }
306
+ $("status").textContent = "done · " + JSON.stringify(tok.decode(ids.slice(promptLen)));
307
+ $("runBtn").disabled = false;
308
+ };
309
+ </script>
310
+ </body>
311
+ </html>