Dataford
Interview QuestionsInterview GuidesExperiencesMock InterviewsPricing
Get started

Predict Fleet Maintenance Cost Drivers

EasyMachine Learning00:00
Practice interviewer
In session
5 left
00:00

Your question is Predict Fleet Maintenance Cost Drivers. Take a moment with it on the right.

Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).

You need to log in / sign up to chat or submit.

Problem

Business Context

RouteOps manages 18,000 delivery vehicles across North America. The fleet operations team wants a model to predict next-month maintenance cost per vehicle and justify whether a Random Forest is a better choice than Linear Regression for this fleet problem.

Dataset

The training data contains monthly vehicle-level records aggregated from telematics, maintenance systems, and driver logs.

Feature GroupCountExamples
Vehicle attributes8vehicle_age_years, make, model, fuel_type, odometer_km
Usage patterns10avg_daily_km, idle_minutes_per_day, harsh_brake_events, route_variability
Maintenance history7repairs_last_90d, days_since_last_service, warranty_flag
Environment5avg_payload_kg, urban_route_pct, avg_temp_c, road_quality_score
Driver behavior4speeding_events, driver_tenure_months, safety_score, night_driving_pct
  • Size: 240K vehicle-month rows, 34 features
  • Target: Continuous — maintenance_cost_next_30d in USD
  • Distribution: Right-skewed with many low-cost months and a long tail of expensive repairs
  • Missing data: ~12% missing in driver behavior fields, ~6% in weather/environment features

Success Criteria

A good solution should outperform a simple linear baseline by at least 15% on MAE and explain when nonlinear models are justified. A production-ready answer should also identify the most important cost drivers for fleet managers.

Constraints

  • Nightly batch scoring for 18,000 vehicles must finish in under 10 minutes
  • Model outputs should support feature importance review by operations analysts
  • Retraining should be feasible monthly on standard cloud CPU instances

Deliverables

  1. Build a baseline Linear Regression model and a Random Forest regressor.
  2. Explain why Random Forest may outperform Linear Regression on this fleet dataset.
  3. Design preprocessing for mixed feature types and missing values.
  4. Evaluate both models using appropriate regression metrics and compare results.
  5. Recommend a production model, retraining cadence, and monitoring plan.