17. When to Deploy Feature Scaling

Question:

One could argue about whether rescaling the financial data is strictly necessary, perhaps we want to keep the information that a $100,000 salary and $40,000,000 in stock options are dramatically different quantities. What if we wanted to cluster based on “from_messages” (the number of email messages sent from a particular email account) and “salary”? Would feature scaling be unnecessary in this case, or critical?