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Learning to Add
KnowledgeMiner has an advantage over other statistical programs
because it can actually learn from a given set of data and
reveal any relationships that might not be obvious, even to
a trained eye.
A simple example that illustrates this ability can be observed
using the Input-Output model method and the data below. If
you haven't done so already, download
the KnowledgeMiner Demo and follow along.
Given some source (X) and target data (Y), there is (almost)
no knowledge about how these data relate. This lack of knowledge
is called a "black box."

The Input-Output model tries to illuminate the "black
box" by creating a mathematical equation that most reliably
imitates the relationship between the source data and the
desired target data. While it does not mimic the exact processes
that created the results, it can derive some general principals
that might prove insightful.
Part One: The Data
Before KnowledgeMiner can be of use to you, it has to
learn. However, there is no need for you to teach KnowledgeMiner
anything or suggest what relationships might exist within
the data. To begin, enter the data below into KnowledgeMiner's
spreadsheet.
| y |
a |
b |
c |
| 9.0000010 |
5.0000010 |
4.0000000 |
5.0000000 |
| 9.0000000 |
3.0000000 |
6.0000000 |
3.0000000 |
| 9.0000000 |
2.0000000 |
7.0000000 |
2.0000000 |
| 9.0000000 |
6.0000000 |
3.0000000 |
6.0000000 |
| 9.0000000 |
8.0000000 |
1.0000000 |
8.0000000 |
| 9.0000000 |
1.0000000 |
8.0000000 |
1.0000000 |
| 9.0000000 |
7.7000000 |
1.3000000 |
7.7000000 |
| 9.0000000 |
8.5000000 |
0.5000000 |
8.5000000 |
| 9.0000000 |
4.8000000 |
4.2000000 |
4.8000000 |
| 9.0000000 |
4.0000000 |
5.0000000 |
4.0000000 |
| 9.0000000 |
9.0000000 |
0.00000 |
9.0000000 |
| 6.0000000 |
22.0000000 |
4.0000000 |
2.0000000 |
Choose the target data by selecting the label for y and then
hold down the Command or Shift key while selecting the three
source columns a, b, c. Here's what the Data Window should
look like in KnowledgeMiner.

At first glance at the data, it appears y = b + c.
We want to find out if KnowledgeMiner can correctly deduce
the correct relationship. To begin, under the Modeling Menu
select Create Input-Output-Model...

KnowledgeMiner will present you with a list of model settings.
In this case, just keep them set to the default settings and
click the Modeling button.
The KnowledgeMiner will then start deducing relationships
in the data and you should see this progress bar:

Part Two: Looking at the Equation
When the modeling is complete, select Modeling Equation under
the Window menu. KnowledgeMiner creates three "true"
models but defaults to showing the best solution. The model
equation correctly identifies the relevant variables as being
b and c. Although column a is nearly identical
to column c except for the last entry, KnowledgeMiner correctly
sees it as unnecessary information.
The simplified equation that KnowledgeMiner comes up with
is found below:
X1 = -0.005530 + 1.000538X3 + 1.000700X4
which is very close to y = b + c.

To test the model, enter data into the columns b and c.

Then, select What-If-Prediction under the Modeling menu.
Enter "1" for the "Forcast Horizon" and
make sure you click "Add prediction data to table automatically"
and click the "Prediction" button.

KnowledgeMiner returns 20.0063667 into column y. Due to the
limitations of numerical precision, it is not possible to
model exact relationships. But KnowledgeMiner does get very
close and more important, discovers some knowledge not necessarily
known, in this case y= b + c.

If your interested in trying more complex examples, check
out the "Logistic Function" example found in the
"Examples Folder" found with the KnowledgeMiner
Demo.
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