Knowing your data is first step for insightful analysis:

Let what ever be modeling algorithms, knowing your data is first step for insightful analysis.

 

Given today's buzz of big data, where more than 90% of the data's usefulness is questionable, it is not bad to stick to basics of the data analysis, i.e. first step, understanding received data properly.

For instance, if you receive a social media data for a single day and if it has 50 million records, knowing existent values format and frequency makes your first step for selecting appropriate modeling algorithm.