PracHub
QuestionsPremiumLearningGuidesInterview PrepNEWCoaches
|Home/Machine Learning/Upstart

Design a Regression Model for Robust Extrapolation Performance

Last updated: Mar 29, 2026

Quick Overview

This question evaluates regression modeling and generalization skills, emphasizing feature engineering, model selection, regularization, and evaluation protocols for producing robust extrapolation beyond the training feature range.

  • medium
  • Upstart
  • Machine Learning
  • Data Scientist

Design a Regression Model for Robust Extrapolation Performance

Company: Upstart

Role: Data Scientist

Category: Machine Learning

Difficulty: medium

Interview Round: Onsite

##### Scenario Machine-learning coding exercise: build a regression model on numerical features that extrapolates well beyond the training range ##### Question Design and implement a regression solution (code expected) that not only fits the training data but also maintains low error when test points fall outside the feature ranges seen in training. Explain feature engineering, model choice, regularization, and how you will evaluate extrapolation performance. ##### Hints Consider linear or monotonic models, polynomial basis with regularization, data standardization, and a hold-out test split drawn from an expanded feature range.

Quick Answer: This question evaluates regression modeling and generalization skills, emphasizing feature engineering, model selection, regularization, and evaluation protocols for producing robust extrapolation beyond the training feature range.

Related Interview Questions

  • Explain L1 vs L2 and ridge vs lasso - Upstart (easy)
  • Implement PAVA spend-smoothing under no-borrowing constraint - Upstart (hard)
  • Derive logistic regression objective and gradients - Upstart (easy)
  • Address Missing Income Bracket in California Housing Data - Upstart (hard)
  • Design Push-Notification System for Airport Surge Pricing - Upstart (medium)
Upstart logo
Upstart
Aug 4, 2025, 10:55 AM
Data Scientist
Onsite
Machine Learning
69
0

Scenario

Onsite machine-learning exercise: your task is to build a regression model using only numerical features that not only fits training data but also keeps low error when test points fall outside the feature ranges seen during training (i.e., extrapolation).

Task

  • Design and implement a regression solution that extrapolates robustly beyond the training feature range.
  • Provide code for:
    1. Data splitting that explicitly creates an out-of-range (OOR) test subset.
    2. A training pipeline with feature engineering, model choice, and regularization.
    3. An evaluation protocol that reports performance in-range vs. out-of-range.
  • Explain your design decisions: feature engineering, model selection, regularization, and extrapolation evaluation methodology.

Assumptions

  • You are given a tabular dataset with numerical features X (shape: n_samples × n_features) and a continuous target y.
  • If no dataset is provided, you may demonstrate with a synthetic dataset and keep the same code path.

Requirements

  1. Use models that can extrapolate (e.g., linear models, low-degree polynomial bases with regularization, or spline bases with linear extrapolation).
  2. Standardize features appropriately.
  3. Regularize to control coefficient growth outside the training range.
  4. Hold out a test split drawn from an expanded feature range and report separate metrics for in-range (IR) and out-of-range (OOR) points.

Hints

  • Consider linear or monotonic models, polynomial basis with regularization, data standardization, and a hold-out test split drawn from an expanded feature range.
  • Tree ensembles without additional structure typically do not extrapolate.

Solution

Show

Comments (0)

Sign in to leave a comment

Loading comments...

Browse More Questions

More Machine Learning•More Upstart•More Data Scientist•Upstart Data Scientist•Upstart Machine Learning•Data Scientist Machine Learning
PracHub

Master your tech interviews with 7,500+ real questions from top companies.

Product

  • Questions
  • Learning Tracks
  • Interview Guides
  • Resources
  • Premium
  • For Universities
  • Student Access

Browse

  • By Company
  • By Role
  • By Category
  • Topic Hubs
  • SQL Questions
  • Compare Platforms
  • Discord Community

Support

  • support@prachub.com
  • (916) 541-4762

Legal

  • Privacy Policy
  • Terms of Service
  • About Us

© 2026 PracHub. All rights reserved.