Issue
I am working on a binary classification problem using Random forest and using LIME explainer to explain the predictions.
I used the below code to generate LIME explanations
import lime
import lime.lime_tabular
explainer = lime.lime_tabular.LimeTabularExplainer(ord_train_t.values, discretize_continuous=True,
feature_names=feat_names,
mode="classification",
feature_selection = "lasso_path",
class_names=rf_boruta.classes_,
categorical_names=output,
kernel_width=10, verbose=True)
i = 969
exp = explainer.explain_instance(ord_test_t.iloc[1,:],rf_boruta.predict_proba,distance_metric = 'euclidean',num_features=5)
I got an output like below
Intercept 0.29625037124439896
Prediction_local [0.46168824]
Right:0.6911888737552843
However, the above is printed as a message in screen
How can we get this info in a dataframe?
Solution
Lime doesn't have direct export-to-dataframe capabilities, so the way to go appears to be appending the predictions to a list and then transforming it into a Dataframe.
Yes, depending on how many predictions you have, this may take a lot of time, since the model has to predict every instance individually.
This is an example I found, the explain_instance
needs to be adjusted to your model args, but follows the same logic.
l=[]
for n in range(0,X_test.shape[0]+1):
exp = explainer.explain_instance(X_test.values[n], clf.predict_proba, num_features=10)
a=exp.as_list()
l.append(a)
df = pd.DataFrame(l)
If you need more than what the as_list() provides, the explainer has more data on it. I ran an example to see what else explain instance would retrieve.
You can, instead of just using as_list(), append to this as_list the other values you need.
a = exp.to_list()
a.append(exp.intercept[1])
l.append(a)
Using this approach you can get the intercept and the prediction_local, for the right value I don't really know which one it would be, but I am certain the object explainer has it somewhere with another name.
Use a breakpoint on your code and explore the explainer, maybe there are other info you would want to save as well.
Answered By - Arson 0
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