Yes you can test the ballast resistor, but most would test it with a known good resistor. Otherwise, you need a VOM (Volts-Ohm meter) to check resistance. Don't remember the ohm rating of that piece, but as i recall it was a fairly low value, and at that it's probably not super critical.
Harbor Freight has a cheapo digital VOM for about 4 bucks or something rediculously cheap like that. Learn how to use that, and study Ohm's Law and you will know 95% more than most others about electricity. Ohms Law defines the relationship between voltage, resistance, and amperage in a direct current circuit. Requires nothing more sophisticated than a little multiplication and division to understand.
