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User Forums => HUGIN GUI Discussion => Topic started by: abul on April 14, 2010, 19:04:07

Title: Analysis Wizard : Predicted value?
Post by: abul on April 14, 2010, 19:04:07
While using the Analysis Wizard for testing the prediction accuracy of the BN model, it gives a confusion matrix in the "Data Accuracy" pane alongwith the error rate.

Also, it marks "red" for cases for which the state was predicted incorrect.

But it does not display the "erroneously" predicted state.

For example, assume a node A having 3 states low, med, high. If the actual state was low (as given in the test case), but it did not predict low, but something else, which led to an error. What was this "something else". Was it med or high?

I need this information because I want to plot the actual state and predicted state for a node of the BN.

Any help will be appreciated.

-Abul
Title: Re: Analysis Wizard : Predicted value?
Post by: Martin on April 15, 2010, 10:38:31
The predicted state is not show per case, but each case is marked green, red or blue if predicted state matches, does not match or observation is missing in data.

Perhaps in a future version of Hugin we should include an extra column in the case table to display the predicted state.


Quote
For example, assume a node A having 3 states low, med, high. If the actual state was low (as given in the test case), but it did not predict low, but something else, which led to an error. What was this "something else". Was it med or high?
I need this information because I want to plot the actual state and predicted state for a node of the BN.

The information you are looking for is not lost, it is summarized in the confusion matrix.

The matrix displays how many times each state was predicted in relation to what was present in the data.

For example:
Code: [Select]
Confusion Matrix:
[actual]
         low       med       high [predicted]
           0           2           0     low
           2           1           2     med
           1           0           2     high

From this matrix we can see that:
In 2 cases: med was the actual state and low was predicted.
In 2 cases: low was the actual state and med was predicted.
In 1 case: med was the actual state and med was predicted.
In 2 cases: high was the actual state and med was predicted.
In 1 case: low was the actual state and high was predicted.
In 2 cases: high was the actual state and high was predicted.


I hope this helps.
Martin