How Many Personas Can I Select for One AI Interview?
Question Type
User Manual Question
Core Answer
Recommended 5-10 personas, system supports maximum of 10.
Recommended Quantity Explained
Standard Configuration: 5-8 Personas
Use Cases:
- Regular product testing
- Feature priority ranking
- Pricing strategy validation
Advantages:
- ✅ Covers main user groups
- ✅ Manageable amount of information, easy to analyze
- ✅ Complete in 50-70 minutes
Persona Combination Recommendations:
- 2-3 core target users
- 2-3 potential users
- 1-2 edge users (for comparison)
In-Depth Research: 10 Personas
Use Cases:
- Complex product decisions
- Multiple market segment comparisons
- Comprehensive user insights
Advantages:
- ✅ Covers more user segments
- ✅ More comprehensive perspectives
- ✅ Discover more potential opportunities
Time Cost:
- 80-100 minutes
Quick Validation: 3-5 Personas
Use Cases:
- Quick concept validation
- Preliminary hypothesis testing
- Limited budget
Limitations:
- ⚠️ Incomplete coverage, may miss key viewpoints
- ⚠️ Small sample size
Recommendations:
- Use only for initial exploration
- For formal decisions, recommend expanding to 5-8 people
How to Choose the Right Quantity?
Decision Factor 1: Research Objective
Exploratory Research (uncertain direction):
- Recommended: 8-10 personas
- Reason: Need more perspectives, discover unexpected insights
Validation Research (validate hypotheses):
- Recommended: 5-8 personas
- Reason: Already have direction, validation is sufficient
Quick Testing (initial concept):
- Recommended: 3-5 personas
- Reason: Quick feedback, reduce trial-and-error costs
Decision Factor 2: User Group Complexity
Single Group (e.g., "25-35 year old working women"):
- Recommended: 5-8 personas
- Reason: Relatively homogeneous group, 5 people sufficient
Multiple Segments (e.g., "different age groups + different occupations"):
- Recommended: 8-10 personas
- Reason: Need to cover each market segment
Examples:
- Sparkling coffee testing (single group): 5 people
- Fitness app multi-group testing: 10 people (beginners, advanced, seniors, pregnancy, rehabilitation)
Decision Factor 3: Time and Budget
| Number | Duration | Token Cost |
|---|---|---|
| 3-5 people | 30-50 minutes | ¥30-60 |
| 5-8 people | 50-70 minutes | ¥50-100 |
| 8-10 people | 80-100 minutes | ¥80-150 |
Recommendations:
- Sufficient budget → 10 people
- Limited budget → 5-8 people
- Quick validation → 3-5 people
Persona Combination Strategies
Strategy 1: Focus on Typical Users
Configuration (5 people):
- 3 core target users (main)
- 2 potential users (expansion)
Use For:
- Product optimization
- Feature testing
- Pricing strategy
Example: Sparkling coffee testing
- 3 health-conscious working women (core)
- 2 price-sensitive students (potential)
Strategy 2: Diversity Mix
Configuration (8 people):
- 2 price-sensitive types
- 2 quality-first types
- 2 brand loyalists
- 2 early adopters
Use For:
- Exploratory research
- New product launch
- Market segmentation
Advantages:
- Discover diverse needs
Strategy 3: Lifecycle Coverage
Configuration (10 people):
- 2 new users (just encountered product)
- 3 active users (currently using)
- 3 churned users (used before, stopped)
- 2 competitor users (comparison)
Use For:
- User retention analysis
- Churn reason exploration
- Competitive comparison
Advantages:
- Full lifecycle insights
- Discover churn reasons and improvement directions
Real-World Cases
Case 1: SaaS Product Pricing (8 People)
Research Objective: Test subscription pricing strategy
Persona Mix:
- 2 small business decision-makers (limited budget)
- 2 mid-size business decision-makers (focus on ROI)
- 2 large enterprise decision-makers (focus on service and support)
- 2 individual users (flexibility priority)
Results:
- Small businesses prefer monthly payment, mid-size prefer annual
- Large enterprises need customized services
- Individual users extremely price-sensitive
Persona Count Reasoning:
- Need to cover 4 user groups
- 2 people per group ensures representativeness
- 8 people provides coverage without overload
Case 2: Fitness App Feature Testing (10 People)
Research Objective: Test "AI Personal Trainer" feature acceptance
Persona Mix:
- 2 fitness beginners (focus on ease of use)
- 2 advanced fitness enthusiasts (focus on professionalism)
- 2 weight loss group (focus on results)
- 2 rehabilitation trainers (focus on safety)
- 2 senior fitness users (focus on gentleness)
Results:
- Beginners most worried about injury from incorrect form
- Advanced users find features not professional enough
- Seniors need simpler interface
Persona Count Reasoning:
- Need to cover 5 user groups
- 2 people per group to find commonalities and differences
- 10 people ensure comprehensive insights
Case 3: Sparkling Coffee New Product Testing (5 People)
Research Objective: Test product concept and pricing
Persona Mix:
- 2 health-conscious types (focus on ingredients)
- 2 price-sensitive types (focus on value)
- 1 social trendsetter type (focus on appearance)
Results:
- Health-conscious worried about sweetener safety
- Price-sensitive find ¥18 expensive
- Social trendsetter focus on packaging appearance
Persona Count Reasoning:
- Single group (25-35 year old working women)
- 5 people sufficient to cover different consumption psychologies
- Quick validation, don't need 10 people
Common Questions
Q1: Can I use fewer than 5 people?
Yes, but not recommended.
- 3-5 people: Only for quick concept validation
- Less than 3 people: Sample size too small, easy to miss key viewpoints
Risks:
- Incomplete coverage, may draw one-sided conclusions
- Miss potential opportunities or risks
Q2: Can I use more than 10 people?
System limits maximum to 10 people.
Reasons:
- Information overload: 10 people already generate 30,000+ word interview content
- Analysis difficulty: Too much information hard to integrate
- Diminishing marginal returns: Beyond 10 people, new findings decrease
If You Need More People:
- Conduct multiple Interview batches
- Or use Discussion Chat group discussion
Q3: How to quickly determine how many people needed?
Simple Formula:
Examples:
- 3 market segments → 6 people (2 per segment)
- 5 market segments → 10 people (2 per segment)
Reason:
- At least 2 people per segment ensures representativeness
- Discover commonalities and differences
Q4: Is there a big quality difference between 5 and 10 people insights?
Depends:
- Single Group: Not much difference, 5 people sufficient
- Multiple Segments: Big difference, 10 people more comprehensive
Recommendations:
- When uncertain, choose 8 people (compromise solution)
- If budget limited, 5 people acceptable, but need precise selection
Best Practices
Recommendation 1: Start with 5, Then Expand
First-Time Use:
- Select 5 people for Interview
- Familiarize with process and output
- If coverage insufficient, add 5 more people
Recommendation 2: Prioritize Diversity
Don't:
- ❌ 5 similar people (e.g., all price-sensitive types)
Do:
- ✅ 5 different types (price-sensitive, quality-first, brand loyalist, early adopter, churned user)
Reason:
- Diversity discovers different perspectives
- Avoid survivorship bias
Recommendation 3: Observe Saturation Point
During Interview Process:
- If by 6-7th person, no new findings emerge
- Means reached "information saturation point"
- Can end early, no need to continue to 10 people
Saves cost and time
Final Takeaway
"5-8 people is the optimal balance: sufficient coverage without information overload. Single group 5 people, multiple segments 8-10 people."
Remember:
- ✅ Recommended: 5-8 people (standard configuration)
- ✅ In-depth research: 8-10 people
- ✅ Quick validation: 3-5 people (initial exploration only)
Related Feature: Interview vs Discussion Document Version: v2.1