Which of the following is not performed by Data Scientist ?

Create reproducible code Answer the question Challenge results Define the question

A key in a data.table allows you to fast and efficiently:

Select rows Create a linear model Use multiple back up classes for your dataset Group the output table

What can you do with the 'by' parameter of a data.table?

Group the output table Select a specific column Add an extra row to your dataset Connect several filter criteria

Decision tree classifiers are what?

Simple and transparent complex and opaque Complex but transparent Simple but opaque

With data-driven decision making, organizations use data for what purpose?

To make all non-trivial business decisions To spy on their competition To manipulate people into buying things they don't need To sell to 3rd parties for a profit