You Get What You Pay For: More on Shaping Behavior

Environments shape behavior even when people don’t.  A more fundamental behavioral process is difficult to imagine. Skilled shapers - people like animal trainers in amusement parks, most outstanding teachers, and many outstanding managers – know their goal in terms of the target behavior before they start the process. This is the great secret of shaping, if there can be any secret about something so fundamental to every learning situation in which humans find themselves.

Shaping is like taking a trip. If you don’t know where you are going, it is hard to get there. Similarly, without a target behavior, it really isn’t possible to shape anything. Sometimes the target behavior is easy to specify. A pigeon’s key peck (see my commentary, “Vive le Pigeon” for why one would want to study a pigeon in the first instance) is easily specifiable in measurable mechanical terms (see “The (Pigeon) Key to Behavior", also in From the Field, for how this is done; the “key” is a small circular plastic disk attached to an electrical switch). Thus, the target behavior is that of the pigeon bringing its beak in contact with the key with sufficient force (about .15 Newtons) that the electric switch on the key is activated.  But what about the shaping of something like “social skills?” More complicated, for sure, and you can’t define them by the closure of an electric switch! But, they can be and have been defined by breaking them down into smaller pieces (e.g., eye contact, smiling, posture, responding back when asked a question, and so forth). Once defined, there is something to work towards.

Another thing about shaping is that what you specify generally is what you get. This is true of any contingency of reinforcement. In shaping a pigeon’s key peck, it is not uncommon for a student shaper/teacher of this response to be moving along well and then just get stuck at some point. It could be said that the pigeon has reached a plateau, but the problem isn’t the pigeon, it is the fact that the pigeon’s environment is no longer requiring further improvements in the behavior toward the goal of pecking the key.  It is like the old adage “ask and ye shall receive,” well, sort of. Ask too much and give too little reward and ye shall receive nada in terms of moving the developing response toward the target.  To keep behavior going, one must achieve a balance between rewarding sufficiently close steps to the final target, while withholding rewards when the behavior is not advancing. Shaping is part science and part art.

Once again in the case of key pecking, it is the case that sometimes the pigeons peck, but the peck is not on the key itself, maybe to one side or the other. If one stops shaping here, the pigeon may or may not ever learn to target its responses on the key itself. It is highly likely that responding will simply stop under these conditions, because without a human observer to reinforce these off-key pecks, they will go unreinforced. Moving the response to the key is easily done by reinforcing approximations of a peck to the targeted location, the key.

This little tale is not intended for shapers of pigeons, though it is germane to their work. The target of my verbal behavior here is people who work with people. If you want to change a person’s behavior, change their environment. Define what you want to see at the end of the shaping/teaching process, reinforce closer and closer approximations to your target, be both liberal and circumspect with reinforcement (give a lot when needed, but always ask for that next approximation before giving it), and don’t stay too long with one response or behavior pattern that is sub-target behavior. It is as it is with children: set limits and children will conform to them; set no limits and ensure that no one wants to be around you, or your out-of-control kids! 

Posted by Andy Lattal, Ph.D.

Dr. Andy Lattal is the Centennial Professor of Psychology at West Virginia University (WVU). Lattal has authored over 150 research articles and chapters on conceptual, experimental, and applied topics in behavior analysis and edited seven books and journal special issues, including APA’s memorial tribute to B. F. Skinner.