title: Interpeting R significance codes for ANOVA table?
body: <p>test data frame:</p>
  
  <pre><code>&gt; foo
        x     y     z
  1 0.191 0.324 0.620
  2 0.229 0.302 0.648
  3 0.191 0.351 0.626
  4 0.229 0.324 0.630
  5 0.152 0.374 0.656
  6 0.191 0.295 0.609
  7 0.229 0.267 0.665
  8 0.152 0.353 0.657
  9 0.152 0.355 0.655
  </code></pre>
  
  <p>Two linear models:</p>
  
  <pre><code>model1 &lt;- lm(z~polym(x,y,degree = 1),data=foo)
  model2 &lt;- lm(z~polym(x,y,degree = 2),data=foo)
  </code></pre>
  
  <p>ANOVA for the two models returns:</p>
  
  <pre><code>&gt; anova(model1,model2)
  Analysis of Variance Table
  
  Model 1: z ~ polym(x, y, degree = 1)
  Model 2: z ~ polym(x, y, degree = 2)
    Res.Df      RSS Df Sum of Sq    F Pr(&gt;F)  
  1      6 0.002988                           
  2      3 0.000169  3   0.00282 16.6  0.023 *
  ---
  Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
  </code></pre>
  
  <p>Why the single <code>*</code>? 0.05 > 0.023 > 0.01, so shouldn't it print a <code>.</code> symbol?</p>