Jack Edwards wrote:
> Well that was long.
That was a great response, Jack. Thanks
Jim4881 wrote:
> Just curious but not overly so.... How are your statistical models
> useful if often incorrect – unless they are not meant to actually
> be applied to anything of value or unless you are working through
> a government grant? Unless they are for amusement only, I miss the
> point of the exercise.
The Generational Dynamics methodology always works, as long as
you follow what I call "the Chaos Theory rules," one of which
is that you can't predict the actions of one person or a group
of people.
I described some of this stuff in my 2009 paper:
** Generational Dynamics Forecasting Methodology (PDF)
**
http://GenerationalDynamics.com/gdgraph ... namics.pdf
Note particularly at the distinction between "short-term forecasting,"
which produces forecasts that are for a small window of time, usually
a few days, but are only 50-60% likely to be correct, versus
"long-term forecasting," which produces forecasts for a large window
of time, usually a few years, but are almost 100% likely to be
correct.
As for your question about whether "short-term forecasting" models
are of any use at all if they aren't guaranteed to be accurate,
here are two such models that I depend on every day:
- Weather forecasts are based on models that are rarely accurate for
more than a few hours. A weather forecast that's more than a few days
out is practically useless. Still, I check the weather forecast each
morning to decide whether to wear a raincoat.
- I take a bus to work each morning, and I check a mobile app that
predicts when the bus will arrive, so that I'll know when to leave my
home for the bus stop. I've discovered that the predictions are
frequently inaccurate, but the inaccuracy is always on the side of
being five or ten minutes too early, so if I get to the bus stop at
the predicted time, then I usually don't have to wait more than five
or ten minutes.
So imperfect models are used by everyone all the time.
Jack describes how he uses his scientific models, and how he adjusts
them when necessary. In many ways, the value of a model lies in the
process of how the model is used, as well as in the model itself.