# Purposeful Error

**URL:** <http://discourse.iapct.org/t/purposeful-error/9303>\
**Category:** CSG1994\
**Created:** [November 16, 1994, 6:14am UTC](http://discourse.iapct.org/t/purposeful-error/9303 "1994-11-16T06:14:07Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Richard\_Marken](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/r/9fc348/32.png) [@Richard\_Marken](http://discourse.iapct.org/u/Richard_Marken)\
**Post date:** [November 16, 1994, 6:14am UTC](http://discourse.iapct.org/t/purposeful-error/9303/1 "1994-11-16T06:14:07Z")

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[From Rick Marken (941115.2220)]

Bruce Abbott (941115.1830 EST) --

> O.K., let's try geometry:

Oh god, no. Not GEOMETRY.

> Apparently the laws of probability, the ones that make p = 0.50 in all  
> these scenarios according to your calculations, are DIFFERENT in  
> California than they are here in Indiana....?

I sure hope so.

> Must be some strange new way of defining "better" and "worse."  
> Why don't you give my way a try? Use:

> Nutrient Rate of Change Before a Tumble - Nutrient Rate of Change  
> After a Tumble. Positive is better, negative is worse. Notice that  
> Nutrient Rate of Change is what is being compared, not Nutrient  
> Level.

OK. I ran a simulation where I determined the probability that  
Nutrient Rate of Change (dNut in your program) is better (or worse)  
after a tumble. If dNut was negative before the tumble and positive  
after then Nutrient Rate of Change got better; my estimate of the  
probability of this happening (over 2560 instances in which dNut was  
negative before the tumble) was .48. If dNut was positive before the  
tumble and negative after then Nutrient Rate of Change got worse; my  
estimate of the probability of this happening (over 2440 instances in  
which dNut was positive before the tumble) was .52. So the actual  
probability of Nutrient Rate of Change getting better after a tumble was  
slightly less than .5; given more samples I think we could have pulled  
it up to chance. And the probability of Nutrient Rate of Change getting  
worse was actually better than chance.

These are not the kind of results that encourage one to believe that  
reinforcements (a positive change in Nutrient Rate of Change after a  
tumble) can shape behavior.

You know. I'm gettin' the impression that you might be one of those  
aliens yourself. You seem to attribute rather remakable powers to  
random consequences of behavior. Maybe you've just been in Indiana  
too long. Be careful, now. Look what happened to B.F. Skinner and  
Dan Quayle.

Best

California Rick