Interpret no significant difference from an experiment

Last updated: November 27, 2025

Quick Overview

An experiment shows a 3% lift with p=0.08. What conclusions can you draw? What are the caveats?

Brex
Analytics & Experimentation
Data Scientist
Brex
November 27, 2025
Data Scientist
Take-home Project
Analytics & Experimentation
Medium

7

5

4,583 solved


An experiment shows a 3% lift with p=0.08. What conclusions can you draw? What are the caveats?

This analytics question from Brex's Take-home Project tests your ability to think critically about data. The interviewer expects you to consider confounding variables, selection bias, and the difference between correlation and causation.

What the Interviewer Expects
  • Design a rigorous experiment with proper randomization and sample size calculation
  • Define primary and guardrail metrics with clear rationale
  • Address novelty effects, network effects, and interference
  • Segment results appropriately and identify heterogeneous treatment effects
  • Propose follow-up analyses when results are ambiguous
Key Topics to Cover
Metric definition and success criteria
Sample size and power calculation
Segmentation and heterogeneous effects
Guardrail metrics
Network effects and interference
How to Approach This
  1. Define success metrics carefully. A good metric is measurable, actionable, and aligned with business goals.
  2. Run experiments long enough to account for novelty effects and weekly seasonality.
  3. Use funnel analysis to identify where users drop off for maximum optimization impact.
  4. Segment results by key dimensions (platform, country, user cohort) to catch hidden patterns.
  5. Consider network effects and interference between treatment and control groups.
Possible Follow-up Questions
  • What would you do if a stakeholder wants to end the experiment early because initial results look good?
  • How would you handle interference between treatment and control?
  • What if the experiment shows a positive short-term effect but you suspect a negative long-term impact?
  • How would you handle seasonality in your experiment?
Sharpen Your Skills on Codemia

Practice similar problems with our interactive workspace, get AI feedback, and track your progress.

Browse Analytics Questions
Sample Answer
Defining the Analysis Framework

Start by framing the problem clearly: 1. **What question are we answering?** Be specific about the hypothesis or business question. 2. **What data d...

Analysis Approach

**Exploratory Analysis**: Start with aggregate trends, then segment by key dimensions (platform, country, user cohort, channel). Look for heterogeneou...


Submit Your Answer
Markdown supported

Related Questions