KNN Loss Function Help

I am using the minimal expected classification cost loss function and I was wondering where I would be able to find the cost incurred for making the prediction (cj) on MATLAB. I am able to find the actual cost on MATLAB but not the cost incurred (cj).

Answer 1

[Vatsal]

Hi,

In MATLAB, you can calculate the cost incurred for making a prediction using the 'loss' function. The 'loss' function in MATLAB has a 'LossFun' argument that allows you to specify the loss function. For minimal expected classification cost, you can set 'LossFun' to 'mincost'.

Here is an example of how you might use it:

L = loss(Mdl, X, Y, 'LossFun', 'mincost'); 

In this example, 'Mdl' represents your model, 'X' represents your predictor data, 'Y' represents your class labels, and 'mincost' is the specified loss function you want to use.

To learn more about the usage and syntax of ‘loss’ function, you may refer to the MathWorks documentation links below:

https://in.mathworks.com/help/stats/classificationlinear.loss.html

I hope this helps!