In the fourth installment of the proofing series, we will discuss duration, the last of the "3 D's". Much of this will be a review of concepts already discussed, but there is some new material to be covered.
The 300 pecks method discussed in the distance article can be applied to building duration also, through withholding the reinforcement. To use 300 pecks to build duration for the sit behavior, I would:
1) Cue the sit. CT (click then treat) when the dog sits.
2) Toss the treat away so that the dog has to break the sit to retrieve the treat.
3) Cue the sit. When the dog sits, count to one, CT. Again, we're going to toss the treat away so that the dog has to get up to retrieve the reinforcement.
4) Cue the sit once again. When the dog sits, count to two, CT. Toss treat to reset, providing the dog with another opportunity to earn reinforcement.
5.) Repeat the sequence, counting to three when the dog sits, and then reinforce.
If at any time you raise the criteria an increment and your dog breaks the sit, return to step one and begin the process again.
Now that you are familiarized with "300 pecks," a question may arise...if I work up to a count of sixty and the dog breaks position, do I have to go all the way back to one in my count? Aidan Bindoff does a nice job of answering this common question in his blog entry on Karen Pryor's site, you can read it for free at: http://www.clickertraining.com/node/1557
Remember, the click ends the behavior. Gale Pryor has a wonderful article with quotes from Karen Pryor on this particular topic. You may read the full text of the article at: http://www.clickertraining.com/node/303
You can also use treat placement to build duration for behaviors by feeding for position without clicking. If your dog is sitting, reinforce on a variable schedule. Let's say your dog is able to maintain the behavior for an average of two counts.
Cue the sit, and when your dog responds, withhold the reinforcement for a count of one, reinforce. Count to three, reinforce. Count to five, reinforce. Count to two, reinforce. Count to one, reinforce. Count to four, click and toss the treat away to reset your dog for another opportunity to be cued for the sit, repeat the process.
This is what is known as a variable interval (VI) reinforcement schedule, as the time interval at which the reinforcement will be delivered varies between trials.
If the dog is able to hold a sit for approximately five seconds, we may reinforce at three seconds, at seven seconds, at one second, at eight seconds, at two seconds, at six seconds. We're averaging approximately five seconds over the course of a designated number of trials.
Work up to higher averages of time your dog is able to maintain the position at a rate that sets your dog up for success. Morgan Spector has called this method "ping ponging" the criteria because the criteria bounces, with highs and lows that are all relative to the baseline time the dog is able to achieve reliably.
Ping ponging the criteria helps keep the game interesting for the dog. If the game always gets harder, the dog may be tempted to give up. Occasionally reinforcing below baseline efforts keeps the dog's confidence level high.
Putting the behavior on a variable reinforcement schedule is often explained by using a slot machine analogy (although a slots player is technically operating on a variable ratio which is based on the number of trials as opposed to a variable interval which is based on the length of time, for the purposes of our discussion, the analogy still functions well).
People do not play slots because they win after every five pulls of the lever. You never know how many lever pulls it will take, but you know that if you try often enough, chances are that it might really pay off!
For anyone who may doubt the power of a variable reinforcement schedule to intensify behaviors, visit a Gambler's Anonymous meeting. That chance at "the big win" can be very addicting (and for those who suffer with a gambling addiction, the reinforcement schedule can become powerful enough to be socially, financially, and emotionally detrimental).
Even when you have worked up to durations measured in minutes rather than seconds, every once in a while you should reinforce a five second stay. After all, sometimes that first quarter pays off with a big win!
Click for you! You've now made it through "the 3 D's" of proofing.
In the next entry, we'll be moving on to proofing for precision and polishing up sloppy behaviors through shaping. I'm sure that until then, you've got plenty to keep you busy working on the 3 D's!