Students conducted a naturalistic observation to study whether people arriving at the library alone would be more likely to hold the door open for a person coming in immediately after them than would people who arrived in pairs. The students made their observations looking through the window of a classroom building across from the library. They chose this position for observation to avoid the potential problem of:

According to my research on studies conducted by various psychologists, I can say that based on the information provided within the question they chose this position for observation to avoid the potential problem of reactivity. In the context of psychology, this term refers to when individuals alter their behavior due to them being aware that they are being observed. Which is why the students stayed out of sight when observing.

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