Newbie: Objective Function I am reading the book "Data Science for Business" by Foster Provost &amp; Tom Fawcett. Only a fourth of the way through.

I am unclear about the concept of Objective Function. I will nevertheless take a stab and would like to seek feedback.

Say that we decided to use standard linear regression for a given problem (assume we have training data). Is the goal of objective function to determine the best parameters (weights) for this training data? 

Thanks in advance!
The objective function is the mathematical equation which combines the parameters in a useful sense. For linear regression this is a simple linear combination of weighted features. 

You will need to choose which objective function is best suited for your problem. Then based on the function you selected you will know what are the model parameters that will need to be fit using an appropriate training method. 

One of the skills of the data scientist is to identify the objective function which has the best likelihood of success given a problem statement.