Look for obvious scratches and scuffs in the floor. High-gloss finishes make scratches and scuffs more readily apparent than semi-gloss finishes. High-gloss finishes also reveal dust and debris on floors more readily than semi-gloss.
Open the curtains or blinds during the day, and pay attention to how much light is reflected off the wood floor. Semi-gloss finishes absorb light, while sunlight will typically cast reflections on a high-gloss finish.
Identify the setting. Many homes have semi-gloss or satin finishes, while commercial spaces are more likely to have high-gloss finished floors.