查看“卡方分布表 Chi-Square Probabilities”的源代码

χ²分布具有可加性，也就是一个卡方加上另一个卡方，还是卡方，用公式表示就是：χ₁²+χ₂²=χ₃²。因此χ₁²=χ₃²-χ₂²，也就是一个卡方减去一个卡方，还是卡方。


查χ²分布表时，按自由度及相应的概率去找到对应的值。

* 单侧概率：χ²单侧概率0.05(11)的查表方法就是，在第一列找到自由度11这一行，在第一行中找到概率0.05这一列，行列的交叉处即是19.675。
* 双侧概念：χ²双侧概率0.05(11)的查表方法就是，在第一列找到自由度11这一行，在第一行中找到概率0.05/2=0.025这一列，行列的交叉处即是21.920 	。

<table class="wikitable" style="text-align: center;">
<tr>
<th>df</th>
<th>0.995</th>
<th>0.99</th>
<th>0.975</th>
<th>0.95</th>
<th>0.90</th>
<th>0.10</th>
<th>0.05</th>
<th>0.025</th>
<th>0.01</th>
<th>0.005</th></tr>
<tr>
<th>1</th>
<td>0.00004</td>
<td>0.00016</td>
<td>0.001</td>
<td>0.004</td>
<td>0.016</td>
<td>2.706</td>
<td>3.841</td>
<td>5.024</td>
<td>6.635</td>
<td>7.879</td>
</tr>
<tr>
<th>2</th>
<td>0.010</td>
<td>0.020</td>
<td>0.051</td>
<td>0.103</td>
<td>0.211</td>
<td>4.605</td>
<td>5.991</td>
<td>7.378</td>
<td>9.210</td>
<td>10.597</td>
</tr>
<tr>
<th>3</th>
<td>0.072</td>
<td>0.115</td>
<td>0.216</td>
<td>0.352</td>
<td>0.584</td>
<td>6.251</td>
<td>7.815</td>
<td>9.348</td>
<td>11.345</td>
<td>12.838</td>
</tr>
<tr>
<th>4</th>
<td>0.207</td>
<td>0.297</td>
<td>0.484</td>
<td>0.711</td>
<td>1.064</td>
<td>7.779</td>
<td>9.488</td>
<td>11.143</td>
<td>13.277</td>
<td>14.860</td>
</tr>
<tr>
<th>5</th>
<td>0.412</td>
<td>0.554</td>
<td>0.831</td>
<td>1.145</td>
<td>1.610</td>
<td>9.236</td>
<td>11.070</td>
<td>12.833</td>
<td>15.086</td>
<td>16.750</td>
</tr>
<tr>
<th>6</th>
<td>0.676</td>
<td>0.872</td>
<td>1.237</td>
<td>1.635</td>
<td>2.204</td>
<td>10.645</td>
<td>12.592</td>
<td>14.449</td>
<td>16.812</td>
<td>18.548</td>
</tr>
<tr>
<th>7</th>
<td>0.989</td>
<td>1.239</td>
<td>1.690</td>
<td>2.167</td>
<td>2.833</td>
<td>12.017</td>
<td>14.067</td>
<td>16.013</td>
<td>18.475</td>
<td>20.278</td>
</tr>
<tr>
<th>8</th>
<td>1.344</td>
<td>1.646</td>
<td>2.180</td>
<td>2.733</td>
<td>3.490</td>
<td>13.362</td>
<td>15.507</td>
<td>17.535</td>
<td>20.090</td>
<td>21.955</td>
</tr>
<tr>
<th>9</th>
<td>1.735</td>
<td>2.088</td>
<td>2.700</td>
<td>3.325</td>
<td>4.168</td>
<td>14.684</td>
<td>16.919</td>
<td>19.023</td>
<td>21.666</td>
<td>23.589</td>
</tr>
<tr>
<th>10</th>
<td>2.156</td>
<td>2.558</td>
<td>3.247</td>
<td>3.940</td>
<td>4.865</td>
<td>15.987</td>
<td>18.307</td>
<td>20.483</td>
<td>23.209</td>
<td>25.188</td>
</tr>
<tr>
<th>11</th>
<td>2.603</td>
<td>3.053</td>
<td>3.816</td>
<td>4.575</td>
<td>5.578</td>
<td>17.275</td>
<td>19.675</td>
<td>21.920</td>
<td>24.725</td>
<td>26.757</td>
</tr>
<tr>
<th>12</th>
<td>3.074</td>
<td>3.571</td>
<td>4.404</td>
<td>5.226</td>
<td>6.304</td>
<td>18.549</td>
<td>21.026</td>
<td>23.337</td>
<td>26.217</td>
<td>28.300</td>
</tr>
<tr>
<th>13</th>
<td>3.565</td>
<td>4.107</td>
<td>5.009</td>
<td>5.892</td>
<td>7.042</td>
<td>19.812</td>
<td>22.362</td>
<td>24.736</td>
<td>27.688</td>
<td>29.819</td>
</tr>
<tr>
<th>14</th>
<td>4.075</td>
<td>4.660</td>
<td>5.629</td>
<td>6.571</td>
<td>7.790</td>
<td>21.064</td>
<td>23.685</td>
<td>26.119</td>
<td>29.141</td>
<td>31.319</td>
</tr>
<tr>
<th>15</th>
<td>4.601</td>
<td>5.229</td>
<td>6.262</td>
<td>7.261</td>
<td>8.547</td>
<td>22.307</td>
<td>24.996</td>
<td>27.488</td>
<td>30.578</td>
<td>32.801</td>
</tr>
<tr>
<th>16</th>
<td>5.142</td>
<td>5.812</td>
<td>6.908</td>
<td>7.962</td>
<td>9.312</td>
<td>23.542</td>
<td>26.296</td>
<td>28.845</td>
<td>32.000</td>
<td>34.267</td>
</tr>
<tr>
<th>17</th>
<td>5.697</td>
<td>6.408</td>
<td>7.564</td>
<td>8.672</td>
<td>10.085</td>
<td>24.769</td>
<td>27.587</td>
<td>30.191</td>
<td>33.409</td>
<td>35.718</td>
</tr>
<tr>
<th>18</th>
<td>6.265</td>
<td>7.015</td>
<td>8.231</td>
<td>9.390</td>
<td>10.865</td>
<td>25.989</td>
<td>28.869</td>
<td>31.526</td>
<td>34.805</td>
<td>37.156</td>
</tr>
<tr>
<th>19</th>
<td>6.844</td>
<td>7.633</td>
<td>8.907</td>
<td>10.117</td>
<td>11.651</td>
<td>27.204</td>
<td>30.144</td>
<td>32.852</td>
<td>36.191</td>
<td>38.582</td>
</tr>
<tr>
<th>20</th>
<td>7.434</td>
<td>8.260</td>
<td>9.591</td>
<td>10.851</td>
<td>12.443</td>
<td>28.412</td>
<td>31.410</td>
<td>34.170</td>
<td>37.566</td>
<td>39.997</td>
</tr>
<tr>
<th>21</th>
<td>8.034</td>
<td>8.897</td>
<td>10.283</td>
<td>11.591</td>
<td>13.240</td>
<td>29.615</td>
<td>32.671</td>
<td>35.479</td>
<td>38.932</td>
<td>41.401</td>
</tr>
<tr>
<th>22</th>
<td>8.643</td>
<td>9.542</td>
<td>10.982</td>
<td>12.338</td>
<td>14.041</td>
<td>30.813</td>
<td>33.924</td>
<td>36.781</td>
<td>40.289</td>
<td>42.796</td>
</tr>
<tr>
<th>23</th>
<td>9.260</td>
<td>10.196</td>
<td>11.689</td>
<td>13.091</td>
<td>14.848</td>
<td>32.007</td>
<td>35.172</td>
<td>38.076</td>
<td>41.638</td>
<td>44.181</td>
</tr>
<tr>
<th>24</th>
<td>9.886</td>
<td>10.856</td>
<td>12.401</td>
<td>13.848</td>
<td>15.659</td>
<td>33.196</td>
<td>36.415</td>
<td>39.364</td>
<td>42.980</td>
<td>45.559</td>
</tr>
<tr>
<th>25</th>
<td>10.520</td>
<td>11.524</td>
<td>13.120</td>
<td>14.611</td>
<td>16.473</td>
<td>34.382</td>
<td>37.652</td>
<td>40.646</td>
<td>44.314</td>
<td>46.928</td>
</tr>
<tr>
<th>26</th>
<td>11.160</td>
<td>12.198</td>
<td>13.844</td>
<td>15.379</td>
<td>17.292</td>
<td>35.563</td>
<td>38.885</td>
<td>41.923</td>
<td>45.642</td>
<td>48.290</td>
</tr>
<tr>
<th>27</th>
<td>11.808</td>
<td>12.879</td>
<td>14.573</td>
<td>16.151</td>
<td>18.114</td>
<td>36.741</td>
<td>40.113</td>
<td>43.195</td>
<td>46.963</td>
<td>49.645</td>
</tr>
<tr>
<th>28</th>
<td>12.461</td>
<td>13.565</td>
<td>15.308</td>
<td>16.928</td>
<td>18.939</td>
<td>37.916</td>
<td>41.337</td>
<td>44.461</td>
<td>48.278</td>
<td>50.993</td>
</tr>
<tr>
<th>29</th>
<td>13.121</td>
<td>14.256</td>
<td>16.047</td>
<td>17.708</td>
<td>19.768</td>
<td>39.087</td>
<td>42.557</td>
<td>45.722</td>
<td>49.588</td>
<td>52.336</td>
</tr>
<tr>
<th>30</th>
<td>13.787</td>
<td>14.953</td>
<td>16.791</td>
<td>18.493</td>
<td>20.599</td>
<td>40.256</td>
<td>43.773</td>
<td>46.979</td>
<td>50.892</td>
<td>53.672</td>
</tr>
<tr>
<th>40</th>
<td>20.707</td>
<td>22.164</td>
<td>24.433</td>
<td>26.509</td>
<td>29.051</td>
<td>51.805</td>
<td>55.758</td>
<td>59.342</td>
<td>63.691</td>
<td>66.766</td>
</tr>
<tr>
<th>50</th>
<td>27.991</td>
<td>29.707</td>
<td>32.357</td>
<td>34.764</td>
<td>37.689</td>
<td>63.167</td>
<td>67.505</td>
<td>71.420</td>
<td>76.154</td>
<td>79.490</td>
</tr>
<tr>
<th>60</th>
<td>35.534</td>
<td>37.485</td>
<td>40.482</td>
<td>43.188</td>
<td>46.459</td>
<td>74.397</td>
<td>79.082</td>
<td>83.298</td>
<td>88.379</td>
<td>91.952</td>
</tr>
<tr>
<th>70</th>
<td>43.275</td>
<td>45.442</td>
<td>48.758</td>
<td>51.739</td>
<td>55.329</td>
<td>85.527</td>
<td>90.531</td>
<td>95.023</td>
<td>100.425</td>
<td>104.215</td>
</tr>
<tr>
<th>80</th>
<td>51.172</td>
<td>53.540</td>
<td>57.153</td>
<td>60.391</td>
<td>64.278</td>
<td>96.578</td>
<td>101.879</td>
<td>106.629</td>
<td>112.329</td>
<td>116.321</td>
</tr>
<tr>
<th>90</th>
<td>59.196</td>
<td>61.754</td>
<td>65.647</td>
<td>69.126</td>
<td>73.291</td>
<td>107.565</td>
<td>113.145</td>
<td>118.136</td>
<td>124.116</td>
<td>128.299</td>
</tr>
<tr>
<th>100</th>
<td>67.328</td>
<td>70.065</td>
<td>74.222</td>
<td>77.929</td>
<td>82.358</td>
<td>118.498</td>
<td>124.342</td>
<td>129.561</td>
<td>135.807</td>
<td>140.169</td>
</tr>
</table>