What is the minimum response rate required for a valid transportation survey in a building with a total of 200 occupants and visitors?

The minimum response rate required for a valid transportation survey is typically a function of achieving a representative sample of the total population in the building. In this scenario, with a total of 200 occupants and visitors, the guideline for a typical survey might suggest aiming for a response rate that allows for statistically significant data collection.

To determine a valid sample size, a common approach is using a percentage of the total population. A commonly accepted minimum threshold is often around 5%, which would correspond to 10 responses in this case. This level is generally seen as enough to gather meaningful insights, ensuring that the sample reflects the diversity of transportation behaviors within the entire population.

The choice indicated aligns with the notion that to appropriately capture varying transportation methods and preferences, a robust set of responses is necessary, and 10 total regular occupants and visitors as a minimum would meet that criterion effectively. This amount helps to ensure that results are valid and reflect the actual transportation modes being utilized by the occupants and visitors of the building.