I want to display on a choropleth map the startups of a particular domain that operate in that state. I have a count of startups by state. How do I normalize so that the map is not represented incorrectly?
Two options to start with:
Use proportional / graduate symbol map of raw values.
Find a denominator for your numerator. That could include population count (startup per capita?), number of working adult population (labor force), number of all companies existing in given spatial unit or number of startups of certain category among all startups to name the few.
For some more inspiration you could Google for 'demography of firms' - it's a strand of geographical research applying demographic methods to analyse companies. AFAIK, University of Groningen has been an origin of quite a bit of work in this area.