Interpret mixed results across segments from an experiment
Last updated: December 18, 2025
Quick Overview
An experiment shows a 3% lift with p=0.08. What conclusions can you draw? What are the caveats?
Workday
December 18, 202515
4
1,257 solved
An experiment shows a 3% lift with p=0.08. What conclusions can you draw? What are the caveats?
This analytics question from Workday's Phone Screen 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
- Define clear success metrics aligned with business goals
- Propose a basic experimental design with control and treatment groups
- Interpret results correctly and draw reasonable conclusions
- Identify obvious confounding variables
Key Topics to Cover
How to Approach This
- Define success metrics carefully. A good metric is measurable, actionable, and aligned with business goals.
- Run experiments long enough to account for novelty effects and weekly seasonality.
- Use funnel analysis to identify where users drop off for maximum optimization impact.
- Segment results by key dimensions (platform, country, user cohort) to catch hidden patterns.
- Consider network effects and interference between treatment and control groups.
Possible Follow-up Questions
- How would you handle an experiment where the control and treatment groups are different sizes?
- 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?
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Browse Analytics QuestionsSample Answer
Problem Setup
The analytical question at hand is to interpret a 3% lift observed in an experiment with a p-value of 0.08. The data we need includes:
- Conversion rates before and after the intervention for both the...
Methodology
Given the 3% lift and a p-value of 0.08, we should conduct a hypothesis test:
- Null Hypothesis (H0): There is no difference in conversion rates between control and treatment groups (lift = 0).
- Al...
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