What is a characteristic of a Variable Ratio (VR) schedule?

A Variable Ratio (VR) schedule is characterized by rewards being provided based on an average number of responses, rather than a fixed number. This means that the reinforcement occurs randomly but on a predictable average. For instance, if a dog receives a treat after an average of three sits, it could get a treat after two sits on one occasion and four on another, but over time, it's the average that remains consistent.

This type of schedule tends to create a high and steady rate of responding because the individual does not know exactly when the next reward will come. This unpredictability encourages continuous engagement, as the possibility of receiving a reward is motivating. This characteristic is especially effective in training as it helps to maintain the behavior over the long term, as dogs may keep trying until they are rewarded.

In contrast, other options like a low and inconsistent response rate would apply to a different type of schedule, such as an inconsistent fixed schedule, while a fixed number of responses refers to Fixed Ratio schedules. The concept of ratio strain also applies to VR schedules but isn't a defining characteristic specific to them. Overall, the average aspect of response requirement stands out as key to understanding the VR schedule.