title: How to find the variance of a linear regression estimator?
body: <p>How can I calculate the variance of <a href="https://i.stack.imgur.com/UUwsf.gif" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/UUwsf.gif" alt="enter image description here"></a> and <a href="https://i.stack.imgur.com/gkv8r.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/gkv8r.png" alt="enter image description here"></a> estimator for a linear regression model where <a href="https://i.stack.imgur.com/bp4B2.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/bp4B2.png" alt="enter image description here"></a>?</p>
  
  <p>Is there a function in R for finding the point estimator like mean, variance of these two estimator?</p>
  
  <p>My data is </p>
  
  <pre><code>fit &lt;- lm(log(TV.Drna$ppDr)~log(TV.Drna$ppTV),data=log(TV.Drna))
  </code></pre>