Let’s talk value-altering effect versus behavior-altering effect. The value-altering effect is an in-the-moment, as in right now, change in how valuable a stimulus is as a reinforcer. So, for example, if there’s an establishing operation like you don’t have gas in your car, in that moment, gas becomes more valuable versus if there’s an abolishing operation like you have a full tank of gas. So, gas is less valuable in that moment. Value-altering effect refers to just that, how reinforcing (how valuable) a reinforcer is in the moment that a person is deprived or satiated.
Then we’ve got the behavior-altering effect. This is also an in-the-moment thing, but it’s a change in the current frequency of behavior when there is an MO. So, with an establishing operation when you need gas, any behaviors that have historically resulted in acquiring gas are going to increase. This behavior-altering effect is called an evocative effect. That has to do with deprivation. Think behavior is being evoked. And of course, if you have a full tank, well, that’s an abolishing operation. Then there’s going to be a decrease in behaviors to acquire gas. And this would be known as an abative effect. Think the behavior is abated.
So, the takeaway: Value-altering means a change in how valuable a reinforcer is, and behavior-altering means a change in the frequency of the behavior. Both of these effects occur and influence behavior at the same time, in the moment that the MO is in effect. And there you have it, easy peasy.