Quantitative Research Methods

Master surveys, analytics, and A/B tests to measure WHAT users do and HOW MANY at scale

Quantitative = Measuring WHAT and HOW MANY

Qualitative research tells you WHY. Quantitative research tells you WHAT and HOW MANY. It measures behavior at scale, validates hypotheses, and gives you the numbers to make data-driven decisions. But remember: numbers without context are meaningless. Always pair quant with qual.

Common Quantitative Methods

Each method measures different aspects of user behavior:

Surveys

Structured questions sent to many users to quantify opinions and behaviors

βœ… Pros

  • β€’ Reach many users fast
  • β€’ Quantifiable data
  • β€’ Easy to analyze
  • β€’ Cheap per response

⚠️ Cons

  • β€’ Low response rates (5-15%)
  • β€’ No follow-up questions
  • β€’ Survey fatigue
  • β€’ Can't explore new topics

Common Metrics:

NPS (Net Promoter Score)CSAT (Customer Satisfaction)Feature importanceFrequency of behavior
Sample Size
100+ responses for confidence (more is better)
Cost
Low ($0-500 for tools)
Timeline
1-2 weeks (design + distribute + collect + analyze)

The A/B Testing Trap

❌ Common Mistake

Stopping test too early when you see a winner. Classic error that leads to false positives.

"Variant B is winning after 2 days! Let's ship it!" β†’ Likely not statistically significant yet

βœ… Right Approach

Calculate required sample size BEFORE running test. Run until you hit that number, then decide.

"We need 5,000 users per variant for 95% confidence. Let's run for 2 weeks minimum."

A/B Test Duration Calculator

Calculate how long to run your A/B test based on traffic and expected improvement:

A/B Test Duration Calculator

βœ… Likely Detectable

Improvement
20.0%
Users Needed (per variant)
3,601
Total Users Needed
7,202
Days to Run Test
~8 days
πŸ’‘

Numbers Don't Tell the Full Story

Analytics show conversion rate dropped 20%. That's WHAT happened. But WHY did it drop? That requires qualitative research. The best product decisions combine both: Use analytics to find the problem. Use interviews to understand the problem. Then build the solution.

Key Takeaways

  • β€’Quantitative methods (surveys, analytics, A/B tests) measure WHAT users do and HOW MANY at scale.
  • β€’Surveys validate hypotheses. Analytics track behavior. A/B tests prove which version performs better.
  • β€’Calculate required sample size BEFORE running A/B tests. Don't stop early when you see a winner.
  • β€’Numbers without context are meaningless. Always pair quantitative data with qualitative insights.