I have not entered a blog post for a while due to a grant which I can now report has found its way to IES. Now I can turn back to my official duties as a PT blogger.
Today we discuss an incredibly important characteristic of learning – bounce. Bounce, a Precision Teaching term for variability, refers to the degree to which a behavior varies over time. We can only see bounce for multiple data points across time, bounce does not lie in a single data point. The larger the bounce the more erratic the behavior. Seemingly “out of control behavior” is high bounce. One day the behavior occurs one or two times and the next day it occurs 40 or 50 times. As an example, I had the chance to inspect the Standard Celeration Chart of young man with autism who had a behavioral target of “aggression.” Aggression referred to behaviors that included hitting, kicking, pushing, and biting. By the way, aggression makes for a very poor pinpoint.
On the chart the total bounce value came to x30.0 (see figure below – counting time = 4 hours). A x30.0 total bounce value describes the relative multiply units of frequency distance found on a Standard Celeration Chart. In other words, we have a bounce envelope comprised of a Down Bounce line, Celeration line, and Up Bounce line (though the actual bounce envelope covers the distance from the down Bounce line to the Up Bounce line). The frequency distance for the “hits other” Movement Cycle (i.e., behavior) falls within the x30.0 bounce envelop measured from the Down Bounce line to the Up Bounce line. Look at the figure below which shows total bounce at x30.0. The individual data points bounce all around the celeration line. From the Down Bounce line to the Up Bounce line the individual behavioral frequencies (recorded data points) fall within the x30.0 spread. With the Down Bounce line resting on the .004 frequency line (that is the frequency line for a behavior with a counting time of 4 hours or 240 minutes) and the Up Bounce line on the .15 line, the range within the envelope is between 1 and 30 instances of “hits other”and everywhere in between. Having such a large bounce value means one day “hits other” could occur 1 time for the observation period or up to 30 times during the next day (for the 4 hour observation period).
If you had Jason in your class and he performed the pinpoint “hits other” once in 4 hours on Monday but the next day he had 23 instances of hits other what would you think? Such a crazy swing in frequency makes it seem like Jason’s behavior is unpredictable. Wide swings in the frequency of behavior are clearly identified by large bounce envelopes. With the SCC, you put on a number on it. The power of the picture and number, the Total Bounce value, puts a hard core scientific measure in the hands of the teacher. The teacher knows the behavior is not unpredictable, just extremely bouncy (namely, a x30.0 Total Bounce).
And as a teacher who must help Jason, the task moves to accounting for the variable(s) at play leading to a x30.0 Total Bounce value across the three weeks. Behavior is the product of an orderly function of a large number of variables. When we see a large bounce value the controlling variables could be appearing episodically. But the controlling variables are there, and when interventions are put in place the Total Bounce value will tell us if we have found those variables controlling behavior.
Look to the right of the x30.0 Total Bounce and see the x3.0 Total Bounce. The stability and regularity with the spread of data instantly communicates the behavior is under better control. In other words, the controlling variables of which the behavior is a function are revealed through the spread of the behavioral frequencies (measured pinpoints). Behavior is a lawful phenomenon. The charted frequencies and how much they bounce speak to the orderliness at play in the person’s current environment. And we can see it all on the chart.