IAE Academy

GATE 2026 DA Q.55: solution and answer

GATE 2026 · DAQ.55 · 2 marks · NAT

Consider that Linear Ridge Regression is being used to learn a prediction function , where and Mean Absolute Error (MAE) is used to measure the prediction error. A weight of 0.20 is associated with the regularizer.

At an intermediate step of the training process, assume that the parameter . In the next step, for the input , the predicted value of is noted. Let the relation between and the true value of be .

The value of the overall regularized loss function for this instance is ______ . (Rounded off to two decimal places)

See the question in the paper

Answer and solution

ANSWER

The overall regularized loss for this instance is .

Official answer: 6.90 to 7.10Source: Official answer key, GATE 2026 DA (IIT Guwahati)

  1. Ridge regression adds an penalty on the weights to the data-fit term. Here the data-fit term is the absolute error (MAE for one instance), so

  2. Prediction: .

  3. True value: .

  4. Error for this single instance: .

  5. Regulariser: , so the penalty is .

  6. Total:

KEY IDEA

Regularized loss = data-fit term (here absolute error, because MAE is specified) + . Compute the prediction first, then the error, then the penalty on the given weight vector.

WATCH OUT FOR

Using squared error instead of absolute error (giving ), or penalising with (not squared) or , or forgetting the penalty term altogether (giving 2).

From the GATE 2026 DA paper. Every question of this paper · Download the full paper · All 4 Regression questions, with notes

More Regression questions