What kind of data can be submitted
For the time being, you can only use numerical data.
Non-numerical data falls in two cathegories: ordered and
non-ordered.
If you have non-ordered data you have to transform it in "dummy variables".
Example:
We have 3 possible atributes for each case : Green,Blue or Red
| Case name |
Caracteristic |
| A |
Red |
| B |
Red |
| C |
Green |
| D |
Blue |
| E |
Blue |
|
Should be changed to:
|
| Case Name |
Red |
Green |
Blue |
| A |
1 |
0 |
0 |
| B |
1 |
0 |
0 |
| C |
0 |
1 |
0 |
| D |
0 |
0 |
1 |
| E |
0 |
0 |
1 |
|
If you have ordered non-numerical data (ordered values define a scale,
for example Cold,Warm,Hot ) you must change it to numerical data maintaining
the relative relationship between cathegories.
Example:
| Case name |
Caracteristic |
| A |
Hot |
| B |
Hot |
| C |
Warm |
| D |
Cold |
| E |
Cold |
|
Should be changed to:
|
| Case Name |
Temperature |
| A |
1 |
| B |
1 |
| C |
2 |
| D |
3 |
| E |
3 |
|
Another important point is that you cannot submit missing data.
If
you have missing data in your database you must assign a value to it (the
average value of other cases, for instance or the median value) before
submitting it.But beware because replacing missing data is notorious for
biasing the data analysis.
|
|
em Português
