title: Will removing a column having same values for all observations affect my model?
body: <p>One of the columns in my dataset has the same value for all observations/rows. 
  Should I remove that column while building a machine learning model?</p>
  
  <p>Will removing this column affect my model/performance metric?</p>
  
  <p>If I replace all the values with a different constant value, will it change the model/performance metric?</p>