If you apply for a data job, this is a commonly asked interview question. It can show your experience and understanding of machine learning.
First of all, noise can occur in both input (X) and output (Y).
Missing Values in X
1. Use the features's mean value from all the available data
2. Ignore the instance
3. Use a mean value from similar items
4. Use another machine learning algorithm to predict the value
Bagging and Boosting
<pre><code> String foo = "bar"; </code></pre>