Courseiva

PMLE Scaling Prototypes into ML Models Practice Question

A data scientist wants to use a pre-trained ResNet model from Keras Applications and fine-tune it on a small custom dataset. Which approach should they take to avoid overfitting?

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Freeze the first few layers and train the rest.

Freezing the earlier layers (which capture general features) and only training the later layers is a common transfer learning approach for small datasets, reducing overfitting.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

  • ✓

    Freeze the first few layers and train the rest.

    Why this is correct

    Freezing early convolutional layers preserves the generic features ResNet learned on ImageNet, so only the later, task-specific layers train. Restricting updates to fewer parameters on a small dataset reduces overfitting while still adapting the model.

  • ✗

    Add more convolutional layers to the model.

    Why it's wrong here

    Adding convolutional layers increases trainable parameters, giving the model greater capacity to memorise a small dataset and worsening overfitting. Fine-tuning should instead freeze the pre-trained base and train a lightweight classifier head. Extra layers are warranted when underfitting a large dataset, not when regularising a small one.

  • ✗

    Use a larger learning rate to speed up training.

    Why it's wrong here

    A larger learning rate accelerates weight updates, which on a small dataset drives the network to memorise training examples rather than generalise. Overfitting is countered by freezing early layers and training few parameters. Large learning rates suit short runs on abundant data, not fine-tuning a pre-trained model on limited samples.

  • ✗

    Train the entire model from scratch on the custom dataset.

    Why it's wrong here

    Training from scratch discards the pre-trained weights and requires far more labelled data than a small custom dataset provides, so the model overfits. Transfer learning exists precisely to reuse those learned features. Scratch training is the right approach only when the domain differs radically and ample labelled data is available.

About these practice questions

One of 775 original PMLE practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →

How Courseiva writes practice questions · Editorial policy

JA

Written by Johnson Ajibi, MSc IT Security

Senior Network & Security Engineer · founder of Courseiva

This PMLE practice question is part of Courseiva's free Google Cloud certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the PMLE exam.