Surveys

Surveys are a passive form of data collection, where the goal is to gather data on existing conditions, attitudes or behavior. Therefore in our example the agency may want to use a survey to sample current residents who live in areas which are currently using wildfire use in their forests.

Experiments

Experiments or scientific studies are an active approach to data collection. In conducting an experiment one varies some environmental condition and then studies the effect of that condition on the outcome. In our example, the agency could simply increase the amount of wildfire use they have in some areas and assess whether the opinion of the people in those areas has changed.

It should be noted that when conducting an experiment as many factors should be held constant as possible.

Example

We could measure the effects of a fertilizer on tree growth on a national forest, but we would have little control over temperature, humidity, insects etc… where as if we conducted the same experiment in a green house we could control all of these variables.