feat: chi-square goodness-of-fit (closes last infer vignette gap)

.gitignore

@@ -18,3 +18,6 @@ doc/reference/
 
 # OS
 .DS_Store
+
+# Local Claude Code settings (plugin toggles, etc.)
+.claude/

CHANGELOG.md

@@ -4,6 +4,12 @@
 
 Full parity with the R `moderndive` and `infer` packages.
 
+- **Chi-square goodness-of-fit** (closes the last `infer` vignette gap):
+  `specify(response=cat).hypothesize(null="point", p={level: prob, ...})` with
+  `generate(type="draw")` and `calculate(stat="Chisq")` now runs a one-variable
+  goodness-of-fit test, and `chisq_test(data, response=, p=)` is the one-line
+  wrapper. `hypothesize(p=...)` accepts a `{level: probability}` mapping.
+
 - **Parity with R `moderndive` PR #144**:
   - `get_correlation()` now accepts multiple right-hand-side predictors
     (`"y ~ x1 + x2"`) — long output by default, `wide=True` for one column per

doc/_build/html/_modules/moderndive/infer/core.html

@@ -333,7 +333,7 @@ <h1>Source code for moderndive.infer.core</h1><div class="highlight"><pre>
         <span class="n">null</span><span class="p">:</span> <span class="nb">str</span><span class="p">,</span>
         <span class="o">*</span><span class="p">,</span>
         <span class="n">mu</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
-        <span class="n">p</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
+        <span class="n">p</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="nb">dict</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
         <span class="n">sigma</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
     <span class="p">)</span> <span class="o">-&gt;</span> <span class="n">Hypothesis</span><span class="p">:</span>
         <span class="k">if</span> <span class="n">null</span> <span class="ow">not</span> <span class="ow">in</span> <span class="p">(</span><span class="s2">&quot;point&quot;</span><span class="p">,</span> <span class="s2">&quot;independence&quot;</span><span class="p">,</span> <span class="s2">&quot;paired independence&quot;</span><span class="p">):</span>
@@ -353,7 +353,7 @@ <h1>Source code for moderndive.infer.core</h1><div class="highlight"><pre>
         <span class="o">*</span><span class="p">,</span>
         <span class="n">order</span><span class="p">:</span> <span class="nb">tuple</span><span class="p">[</span><span class="nb">object</span><span class="p">,</span> <span class="nb">object</span><span class="p">]</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
         <span class="n">mu</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
-        <span class="n">p</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
+        <span class="n">p</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="nb">dict</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
         <span class="n">sigma</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
     <span class="p">)</span> <span class="o">-&gt;</span> <span class="n">ObservedStatistic</span><span class="p">:</span>
 <span class="w">        </span><span class="sd">&quot;&quot;&quot;Compute the observed statistic (no resampling).&quot;&quot;&quot;</span>
@@ -407,7 +407,7 @@ <h1>Source code for moderndive.infer.core</h1><div class="highlight"><pre>
     <span class="n">spec</span><span class="p">:</span> <span class="n">Specification</span>
     <span class="n">null</span><span class="p">:</span> <span class="nb">str</span>
     <span class="n">mu</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span>
-    <span class="n">p</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span>
+    <span class="n">p</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="nb">dict</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span>
     <span class="n">sigma</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span>
 
     <span class="k">def</span><span class="w"> </span><span class="nf">generate</span><span class="p">(</span>
@@ -449,7 +449,7 @@ <h1>Source code for moderndive.infer.core</h1><div class="highlight"><pre>
     <span class="n">plans</span><span class="p">:</span> <span class="nb">list</span><span class="p">[</span><span class="n">np</span><span class="o">.</span><span class="n">ndarray</span><span class="p">]</span> <span class="o">=</span> <span class="n">field</span><span class="p">(</span><span class="nb">repr</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span>
     <span class="n">shifted_response</span><span class="p">:</span> <span class="n">np</span><span class="o">.</span><span class="n">ndarray</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="n">field</span><span class="p">(</span><span class="n">default</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="nb">repr</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span>
     <span class="n">hyp_mu</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span>
-    <span class="n">hyp_p</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span>
+    <span class="n">hyp_p</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="nb">dict</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span>
     <span class="n">hyp_sigma</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span>
 
     <span class="c1"># --- single-variable / two-group statistics ---------------------------</span>
@@ -567,12 +567,20 @@ <h1>Source code for moderndive.infer.core</h1><div class="highlight"><pre>
     <span class="k">elif</span> <span class="nb">type</span> <span class="o">==</span> <span class="s2">&quot;draw&quot;</span><span class="p">:</span>
         <span class="k">if</span> <span class="n">hypothesis</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">or</span> <span class="n">hypothesis</span><span class="o">.</span><span class="n">p</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span>
             <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">&quot;type=&#39;draw&#39; requires hypothesize(null=&#39;point&#39;, p=...)&quot;</span><span class="p">)</span>
-        <span class="n">success</span> <span class="o">=</span> <span class="n">spec</span><span class="o">.</span><span class="n">success</span>
-        <span class="n">nonsuccess</span> <span class="o">=</span> <span class="s2">&quot;</span><span class="se">\x00</span><span class="s2">not_success&quot;</span>
-        <span class="n">p0</span> <span class="o">=</span> <span class="n">hypothesis</span><span class="o">.</span><span class="n">p</span>
-        <span class="k">for</span> <span class="n">_</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="n">reps</span><span class="p">):</span>
-            <span class="n">draws</span> <span class="o">=</span> <span class="n">rng</span><span class="o">.</span><span class="n">random</span><span class="p">(</span><span class="n">n</span><span class="p">)</span> <span class="o">&lt;</span> <span class="n">p0</span>
-            <span class="n">plans</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">np</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">draws</span><span class="p">,</span> <span class="n">success</span><span class="p">,</span> <span class="n">nonsuccess</span><span class="p">)</span><span class="o">.</span><span class="n">astype</span><span class="p">(</span><span class="nb">object</span><span class="p">))</span>
+        <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">hypothesis</span><span class="o">.</span><span class="n">p</span><span class="p">,</span> <span class="nb">dict</span><span class="p">):</span>
+            <span class="c1"># Multi-level draw for chi-square goodness-of-fit: sample each</span>
+            <span class="c1"># replicate&#39;s categories from the hypothesized proportions.</span>
+            <span class="n">levels</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="n">hypothesis</span><span class="o">.</span><span class="n">p</span><span class="o">.</span><span class="n">keys</span><span class="p">())</span>
+            <span class="n">probs</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">asarray</span><span class="p">(</span><span class="nb">list</span><span class="p">(</span><span class="n">hypothesis</span><span class="o">.</span><span class="n">p</span><span class="o">.</span><span class="n">values</span><span class="p">()),</span> <span class="n">dtype</span><span class="o">=</span><span class="nb">float</span><span class="p">)</span>
+            <span class="k">for</span> <span class="n">_</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="n">reps</span><span class="p">):</span>
+                <span class="n">plans</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">rng</span><span class="o">.</span><span class="n">choice</span><span class="p">(</span><span class="n">levels</span><span class="p">,</span> <span class="n">size</span><span class="o">=</span><span class="n">n</span><span class="p">,</span> <span class="n">p</span><span class="o">=</span><span class="n">probs</span><span class="p">)</span><span class="o">.</span><span class="n">astype</span><span class="p">(</span><span class="nb">object</span><span class="p">))</span>
+        <span class="k">else</span><span class="p">:</span>
+            <span class="n">success</span> <span class="o">=</span> <span class="n">spec</span><span class="o">.</span><span class="n">success</span>
+            <span class="n">nonsuccess</span> <span class="o">=</span> <span class="s2">&quot;</span><span class="se">\x00</span><span class="s2">not_success&quot;</span>
+            <span class="n">p0</span> <span class="o">=</span> <span class="n">hypothesis</span><span class="o">.</span><span class="n">p</span>
+            <span class="k">for</span> <span class="n">_</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="n">reps</span><span class="p">):</span>
+                <span class="n">draws</span> <span class="o">=</span> <span class="n">rng</span><span class="o">.</span><span class="n">random</span><span class="p">(</span><span class="n">n</span><span class="p">)</span> <span class="o">&lt;</span> <span class="n">p0</span>
+                <span class="n">plans</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">np</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">draws</span><span class="p">,</span> <span class="n">success</span><span class="p">,</span> <span class="n">nonsuccess</span><span class="p">)</span><span class="o">.</span><span class="n">astype</span><span class="p">(</span><span class="nb">object</span><span class="p">))</span>
     <span class="k">else</span><span class="p">:</span>  <span class="c1"># bootstrap</span>
         <span class="k">if</span> <span class="n">hypothesis</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span> <span class="ow">and</span> <span class="n">hypothesis</span><span class="o">.</span><span class="n">null</span> <span class="o">==</span> <span class="s2">&quot;point&quot;</span> <span class="ow">and</span> <span class="n">hypothesis</span><span class="o">.</span><span class="n">mu</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span>
             <span class="n">shifted</span> <span class="o">=</span> <span class="n">_resample</span><span class="o">.</span><span class="n">shift_for_point_null</span><span class="p">(</span>
@@ -770,7 +778,7 @@ <h1>Source code for moderndive.infer.core</h1><div class="highlight"><pre>
     <span class="n">order</span><span class="p">:</span> <span class="nb">tuple</span><span class="p">[</span><span class="nb">object</span><span class="p">,</span> <span class="nb">object</span><span class="p">]</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
     <span class="n">null</span><span class="p">:</span> <span class="nb">str</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
     <span class="n">mu</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
-    <span class="n">p</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
+    <span class="n">p</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="nb">dict</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
     <span class="n">sigma</span><span class="p">:</span> <span class="nb">float</span> <span class="o">|</span> <span class="kc">None</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span>
 <span class="p">)</span> <span class="o">-&gt;</span> <span class="n">ObservedStatistic</span><span class="p">:</span>
 <span class="w">    </span><span class="sd">&quot;&quot;&quot;Shortcut for ``specify() |&gt; [hypothesize()] |&gt; calculate()``.</span>