How accurate is the infrared trail counter?
All infrared trail counters under count when people travel side by side, or in tight groups. Therefore, it can be said that trail counters yield estimates rather than absolutes. It is difficult to give a single number regarding accuracy because it is dependent upon various factors: how people typically use the trail (single file or side by side), how far apart people are spaced, how busy the trail is, trail width, how a counter is set up, etc. If the trail is narrow and people travel single file and spaced apart, you can expect high accuracy (95 to 100%); if the trail is wide and people typically travel side by side or tight groups, you can expect accuracy in the range of 75% to 90%. An important question to ask is what level of accuracy do I need to answer my management-related questions? Generally, acceptable accuracy can be defined as the level sufficient to detect changes that are significant to management decisions (Hendee et al. 1990). In the real world of management decisions, o
