<p>A two sample t-test assumes independence and normality. An ANOVA assumes independence, normality, and equal variance. It’s a bit tough to tell, but the overall assumption of equal variance seems reasonable. Normality is a bit of a hard sell within groups or overall. Nevertheless, most analysts would march ahead with the analysis despite these violations of assumptions. We can discuss how you might think and talk about this in class.</p>
<p>The global mean is</p>
<pre class="r"><code>mean(df$weeks_alive)</code></pre>
<p>A two sample t-test assumes independence and normality. An ANOVA assumes independence, normality, and equal variance. It’s a bit tough to tell, but the overall assumption of equal variance seems reasonable. Normality is a bit of a hard sell within groups or overall. Nevertheless, most analysts would march ahead with the analysis despite these violations of assumptions. We can discuss how you might think and talk about this in class.</p>
<p>The global mean is</p>
<pre class="r"><code>mean(df$weeks_alive)</code></pre>