Keyword Volume Relational Accuracy

First, quick disclosure: I am Russ Jones, Principal Search Scientist at Moz and I work directly on the model that predicts search volume. It is impossible to know the exact search volume for a keyword in Google. The methodologies available to us (Google Adwords Keyword Planner, Traffic Estimator, and Google Trends) are all problematic in one way or another. But this doesn’t mean we are hopelessly lost regarding our predictions of search volume. One thing we can analyze is the relationship between keywords rather than their exact volume. For example, Google Trends doesn’t provide us the exact search numbers, but it does provide us a comparison of keywords. Theoretically, the relationship between 2 keywords in Google Trends (lets say 3:1 because keyword...