trinhan / crc-ihc-classification

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Questions about model evaluation parts #4

Open SeYoungKim opened 6 years ago

SeYoungKim commented 6 years ago

Hello

I'm trying to understand the code. And... I have questions about model evaluation parts...

About evaluating RF classifier with the training data...

As I understand, the Random Forest classifier is trained by using the whole AMC dataset. So AMC dataset is used as a training set and a set of the other data(LUMC, CAIRO, CAIRO2) is used as a validation set.

So when the classifier was trained with AMC dataset, its OOB error rate was 19.83%.

And in the paper, Fig 1. C says its accuracy is 87.14%.

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So I looked for the part in the [4.1.1 Training the classifier, Supplementary Info...]. There was a code snippet for drawing the table(but I couldn't find it in the current repo.. is there a different source file which is same as [Supplementary Info...]?)

I guess the result of the gold-standard transcriptome-based classifier means the GE result and... isn't it the Class column values in AMCclinical.csv?

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Seems like the labels used for training were used for evaluation...

Is it correct that 87.14% is the result of evaluation with the training data?

If so, isn't it that only the OOB value has meaning?

Thank you

SeYoungKim commented 6 years ago

Isn't the accuracy of the RF on the training set(per sample, not per patient) is (almost)100%?

I tried this again in the different environment with the same data and I got similar answers...

About 20% of oob error and almost 100% of accuracy on the training data..!

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SeYoungKim commented 6 years ago

I have one more question about evaluation...

There is a histogram like below in [Supplementary Information...] and I wonder if this graph is for test set accuracies in k-fold cross validation...

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I'm reading this...

image image

As I understand, you're performing k-fold cross validation...

and this table (rfpred) is the result from the one time evaluation.(70%)

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And there is a picture of some distribution like below...

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My question is, Is this distribution is for the OOB distribution or k-fold cross validation...?(200 times)

The code drawing the histogram (Core classification accuracy) is using the result from the ClassifyPrediction and I couldn't find it from the current repo...

There are two lines: "The accuracy for the above is 0.7. This is repeated 200 times" and "Using this method, the OOB distribution and prediction accuracy is as follows". Here I can't make out which one the histogram is for...

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