Memory System A/B Test Design¶
Version: 1.0.0 Date: 2025-11-03 Status: Design Complete Goal: Prove (or disprove) that Neo4j memory provides measurable value vs SQLite memory
Executive Summary¶
Test Objective¶
Quantitatively compare Neo4j-based memory system vs SQLite-based memory system to determine:
- Does memory provide measurable benefit? (vs no memory baseline)
- Does Neo4j provide measurable benefit over SQLite? (if memory proves valuable)
- What are the specific improvements? (time, quality, error prevention)
Key Design Principles¶
Following project philosophy:
- Ruthless Simplicity: Measure what matters, ignore vanity metrics
- Measurement First: Establish baseline before optimization
- Statistical Rigor: Proper sample sizes, confidence intervals, p-values
- Fair Comparison: Control for confounding variables
- Transparent Reporting: Show raw data and statistical analysis
Expected Outcomes¶
Based on research findings, we hypothesize:
- Memory vs No Memory: 20-35% improvement in repeat task efficiency
- Neo4j vs SQLite: Minimal difference at <100k records, 10-30% improvement at scale
- Break-even Point: 4-6 weeks after implementation
1. Test Methodology¶
1.1 Three-Way Comparison¶
We will test three configurations:
| Configuration | Description | Purpose |
|---|---|---|
| Control | No memory system (current baseline) | Establish if memory provides value |
| SQLite | SQLite-based memory (Phase 1 implementation) | Measure basic memory effectiveness |
| Neo4j | Neo4j-based memory (Phase 3 implementation) | Measure graph capabilities value |
1.2 Test Structure¶
┌─────────────────────────────────────────────────────────────┐
│ Phase 1: Baseline Establishment (No Memory) │
│ - Run 10 scenarios × 5 iterations = 50 baseline runs │
│ - Collect: time, errors, quality scores │
│ - Establish statistical baseline │
└─────────────────────────────────────────────────────────────┘
↓
┌─────────────────────────────────────────────────────────────┐
│ Phase 2: SQLite Memory Testing │
│ - Run same 10 scenarios × 5 iterations = 50 SQLite runs │
│ - Collect same metrics │
│ - Compare to baseline with statistical tests │
└─────────────────────────────────────────────────────────────┘
↓
┌─────────────────────────────────────────────────────────────┐
│ Phase 3: Neo4j Memory Testing (ONLY if Phase 2 succeeds) │
│ - Run same 10 scenarios × 5 iterations = 50 Neo4j runs │
│ - Collect same metrics │
│ - Compare to SQLite with statistical tests │
└─────────────────────────────────────────────────────────────┘
↓
┌─────────────────────────────────────────────────────────────┐
│ Phase 4: Analysis & Decision │
│ - Statistical significance testing │
│ - Effect size calculations │
│ - Cost-benefit analysis │
│ - Final recommendation │
└─────────────────────────────────────────────────────────────┘
1.3 Fair Comparison Requirements¶
To ensure valid comparison:
- Same Agent Prompts: Identical agent definitions across all configurations
- Same Scenarios: Identical task definitions and inputs
- Same Environment: Same machine, same Claude model, same dependencies
- Isolated Runs: Clear memory/state between test runs
- Randomization: Scenario order randomized to prevent ordering effects
- Blinding: Automated test harness (no human bias in execution)
2. Test Scenarios¶
2.1 Scenario Selection Criteria¶
Each scenario must:
- Representative: Common real-world coding task
- Repeatable: Can be run multiple times with consistent setup
- Memory-Relevant: Benefits from learning/context
- Measurable: Clear success/failure criteria
- Time-Bounded: Completes in 2-10 minutes
2.2 Scenario Catalog¶
Scenario 1: Repeat Authentication Implementation¶
Type: Learning from repetition Expected Memory Benefit: HIGH (50-70% time reduction on second attempt)
Task: Implement JWT authentication for REST API
First Iteration:
- No memory available
- Agent explores options, makes decisions
- Records: implementation pattern, common pitfalls
Second Iteration (different project):
- Memory available from first iteration
- Should reuse proven pattern
- Should avoid previous pitfalls
Metrics:
- Time to complete (seconds)
- Number of errors encountered
- Code quality score (automated analysis)
- Pattern reuse (did agent reference previous solution?)
Scenario 2: Cross-Project Validation Pattern¶
Type: Pattern transfer Expected Memory Benefit: MEDIUM (25-40% improvement)
Task: Implement input validation for user registration endpoint
Context:
- Project A: Implement email validation
- Project B: Implement similar validation (different field)
With Memory:
- Should recognize similar validation pattern
- Should reuse regex/logic approach
- Should avoid repeated edge case bugs
Metrics:
- Code similarity to proven pattern
- Edge cases covered
- Time to implementation
- Test coverage
Scenario 3: Error Resolution Learning¶
Type: Error pattern recognition Expected Memory Benefit: HIGH (60-80% faster resolution)
Task: Debug "TypeError: 'NoneType' object is not subscriptable"
First Occurrence:
- Agent investigates multiple possibilities
- Eventually finds: missing null check
- Records: error signature → solution pattern
Second Occurrence:
- Same error signature in different context
- Should quickly identify null check issue
- Should apply proven solution
Metrics:
- Time to identify root cause
- Time to resolution
- Solution quality
- Memory pattern match accuracy
Scenario 4: API Design with Past Examples¶
Type: Design pattern application Expected Memory Benefit: MEDIUM (30-45% quality improvement)
Task: Design REST API for new domain entity
With Memory:
- Access to previous API designs
- See patterns that worked well
- Avoid anti-patterns from past
Without Memory:
- Make decisions from scratch
- May repeat previous mistakes
Metrics:
- API design consistency score
- Adherence to REST principles
- Error handling completeness
- Documentation quality
Scenario 5: Code Review with Historical Context¶
Type: Quality improvement Expected Memory Benefit: MEDIUM (40-55% more issues found)
Task: Review PR for security vulnerabilities
With Memory:
- Recall previous vulnerabilities found
- Check for similar patterns
- Apply learned security principles
Without Memory:
- Generic security checklist
- May miss patterns seen before
Metrics:
- Number of valid issues found
- False positive rate
- Critical issues caught
- Review thoroughness score
Scenario 6: Test Generation Pattern¶
Type: Procedural memory Expected Memory Benefit: MEDIUM (35-50% better coverage)
Task: Generate unit tests for authentication module
With Memory:
- Recall test patterns for auth
- Include edge cases from past
- Cover previously-missed scenarios
Metrics:
- Test coverage percentage
- Edge cases covered
- Test quality score
- Time to generate complete test suite
Scenario 7: Performance Optimization¶
Type: Optimization pattern recognition Expected Memory Benefit: LOW-MEDIUM (20-35% improvement)
Task: Optimize slow database query
With Memory:
- Recall previous optimization strategies
- Apply proven indexing patterns
- Avoid ineffective optimizations tried before
Metrics:
- Query performance improvement (%)
- Time to identify bottleneck
- Optimization approach quality
Scenario 8: Refactoring Legacy Code¶
Type: Refactoring strategy Expected Memory Benefit: MEDIUM (30-45% improvement)
Task: Refactor monolithic function into modular components
With Memory:
- Apply previous refactoring patterns
- Use proven module boundaries
- Avoid previous refactoring mistakes
Metrics:
- Cyclomatic complexity reduction
- Number of modules created
- Test coverage maintained
- Refactoring time
Scenario 9: Integration Error Resolution¶
Type: Integration debugging Expected Memory Benefit: HIGH (50-70% faster resolution)
Task: Debug failing integration test (external API timeout)
First Time:
- Investigate multiple hypotheses
- Check API docs, network, code
- Find: retry logic missing
With Memory:
- Recognize timeout pattern
- Quickly check retry logic
- Apply proven solution
Metrics:
- Debugging time
- Hypotheses explored
- Correct solution speed
Scenario 10: Multi-File Feature Implementation¶
Type: Complex feature with dependencies Expected Memory Benefit: MEDIUM (25-40% improvement)
Task: Implement user authentication feature (controller, service, tests, docs)
With Memory:
- Recall feature implementation patterns
- Use proven file organization
- Apply consistent naming conventions
- Include all necessary components from start
Metrics:
- Implementation completeness
- Code consistency score
- Number of revision cycles
- Total implementation time
2.3 Scenario Memory Pre-Seeding¶
Critical Decision: How to handle memory state for fair testing?
Option A: Clean Slate (Recommended for Phase 1)¶
- Approach: Each test run starts with empty memory
- Pro: Fair comparison, no confounding variables
- Con: Doesn't test long-term memory accumulation
- Use Case: Baseline establishment, initial memory validation
Option B: Pre-Seeded Memory (For Phase 2)¶
- Approach: Seed memory with N representative entries before test
- Pro: Tests realistic memory state
- Con: Requires careful seed data curation
- Use Case: Testing memory retrieval effectiveness
Option C: Progressive Memory Building (For Phase 3)¶
- Approach: Run scenarios sequentially, building memory over time
- Pro: Tests real-world accumulation
- Con: Later scenarios affected by earlier ones
- Use Case: Long-term effectiveness testing
Decision: Use Option A for baseline comparison, then Option B for retrieval testing.
3. Metrics Collection¶
3.1 Primary Metrics (Objective)¶
These metrics are automatically collected by test harness:
3.1.1 Time Metrics¶
class TimeMetrics:
execution_time: float # Total task execution time (seconds)
time_to_first_action: float # Time until agent takes first action
decision_time: float # Time spent in decision-making
implementation_time: float # Time spent writing code
Collection Method: Timestamp at task start, action points, and completion.
3.1.2 Quality Metrics¶
class QualityMetrics:
test_pass_rate: float # Percentage of tests passing (0-1)
code_complexity: int # Cyclomatic complexity
error_count: int # Number of errors during execution
revision_cycles: int # Number of code revision iterations
pylint_score: float # Automated code quality score (0-10)
Collection Method: Run automated analysis tools on generated code.
3.1.3 Memory Usage Metrics¶
class MemoryMetrics:
memory_retrievals: int # Number of memory queries
memory_hits: int # Number of relevant memories found
memory_applied: int # Number of memories actually used
retrieval_time: float # Time spent retrieving memories (ms)
Collection Method: Instrument memory system with logging.
3.1.4 Output Metrics¶
class OutputMetrics:
lines_of_code: int # LOC generated
files_modified: int # Number of files changed
test_coverage: float # Test coverage percentage (0-100)
documentation_completeness: float # Doc completeness score (0-1)
Collection Method: Analyze generated artifacts.
3.2 Secondary Metrics (Qualitative)¶
These metrics require manual assessment (sample subset):
3.2.1 Decision Quality¶
class DecisionQuality:
architecture_appropriateness: int # 1-5 scale
pattern_selection_quality: int # 1-5 scale
error_handling_completeness: int # 1-5 scale
edge_case_coverage: int # 1-5 scale
Assessment Method: Expert review of 20% sample (10 runs), scoring rubric.
3.2.2 Pattern Recognition¶
class PatternRecognition:
recognized_previous_solution: bool # Did agent reference past work?
adapted_pattern_appropriately: bool # Was adaptation correct?
avoided_previous_errors: bool # Prevented repeated mistakes?
Assessment Method: Manual analysis of agent reasoning and decision logs.
3.3 Metric Collection Implementation¶
# Test harness will collect metrics automatically
class MetricsCollector:
def __init__(self, scenario_id: str, config: str):
self.scenario_id = scenario_id
self.config = config # "control", "sqlite", or "neo4j"
self.metrics = {}
self.start_time = None
def start_collection(self):
"""Begin metric collection for a test run."""
self.start_time = time.time()
self.metrics = {
"scenario_id": self.scenario_id,
"config": self.config,
"timestamp": datetime.now().isoformat(),
"time": {},
"quality": {},
"memory": {},
"output": {}
}
def record_time_metric(self, name: str, value: float):
"""Record a time-based metric."""
self.metrics["time"][name] = value
def record_quality_metric(self, name: str, value: Union[int, float]):
"""Record a quality metric."""
self.metrics["quality"][name] = value
def record_memory_metric(self, name: str, value: Union[int, float]):
"""Record a memory usage metric."""
self.metrics["memory"][name] = value
def record_output_metric(self, name: str, value: Union[int, float]):
"""Record an output metric."""
self.metrics["output"][name] = value
def finalize(self) -> dict:
"""Finalize and return collected metrics."""
self.metrics["time"]["total_execution"] = time.time() - self.start_time
return self.metrics
4. Statistical Analysis¶
4.1 Sample Size Calculation¶
Goal: Detect 20% improvement with 80% power at α=0.05
# Using standard power analysis
from scipy.stats import power
from statsmodels.stats.power import tt_ind_solve_power
# Expected effect size: 20% improvement
# Cohen's d ≈ 0.5 (medium effect)
# Power = 0.80
# Alpha = 0.05
sample_size = tt_ind_solve_power(
effect_size=0.5,
power=0.80,
alpha=0.05,
ratio=1.0,
alternative='two-sided'
)
# Result: ~64 observations per group
# We'll use: 10 scenarios × 5 iterations = 50 per group
# This gives ~75% power (acceptable for initial testing)
Decision: 5 iterations per scenario = 50 total runs per configuration
This provides:
- 75% power to detect 20% improvement
- 95% confidence intervals
- Reasonable time investment (~8-10 hours per configuration)
4.2 Statistical Tests¶
4.2.1 Primary Comparison: Paired T-Test¶
from scipy.stats import ttest_rel
def compare_configurations(baseline_times, treatment_times):
"""
Compare execution times between configurations.
Uses paired t-test because same scenarios run with different configs.
"""
# Paired t-test (same scenarios, different conditions)
t_statistic, p_value = ttest_rel(baseline_times, treatment_times)
# Calculate effect size (Cohen's d for paired data)
diff = np.array(treatment_times) - np.array(baseline_times)
effect_size = np.mean(diff) / np.std(diff)
# Calculate confidence interval
conf_interval = stats.t.interval(
0.95,
len(diff) - 1,
loc=np.mean(diff),
scale=stats.sem(diff)
)
return {
"t_statistic": t_statistic,
"p_value": p_value,
"effect_size": effect_size,
"mean_diff": np.mean(diff),
"conf_interval_95": conf_interval,
"significant": p_value < 0.05
}
4.2.2 Multiple Comparisons Correction¶
from statsmodels.stats.multitest import multipletests
def analyze_all_metrics(baseline_data, treatment_data, metrics):
"""
Analyze multiple metrics with Bonferroni correction.
Prevents false positives from multiple testing.
"""
results = {}
p_values = []
for metric in metrics:
baseline_values = [run[metric] for run in baseline_data]
treatment_values = [run[metric] for run in treatment_data]
result = compare_configurations(baseline_values, treatment_values)
results[metric] = result
p_values.append(result["p_value"])
# Apply Bonferroni correction
corrected = multipletests(p_values, alpha=0.05, method='bonferroni')
for i, metric in enumerate(metrics):
results[metric]["corrected_p_value"] = corrected[1][i]
results[metric]["significant_corrected"] = corrected[0][i]
return results
4.2.3 Effect Size Interpretation¶
Following Cohen's guidelines:
| Effect Size ( | d | ) | Interpretation | Example |
|---|---|---|---|---|
| < 0.2 | Negligible | Not practically significant | ||
| 0.2 - 0.5 | Small | Noticeable but minor improvement | ||
| 0.5 - 0.8 | Medium | Substantial improvement | ||
| > 0.8 | Large | Major improvement |
Decision Criteria:
- Proceed with SQLite: Medium effect (d > 0.5) AND p < 0.05
- Proceed with Neo4j: Medium effect (d > 0.5) AND p < 0.05 AND practical benefit > complexity cost
4.3 Confidence Intervals¶
Report 95% confidence intervals for all metrics:
def calculate_confidence_intervals(data, confidence=0.95):
"""Calculate confidence intervals for metrics."""
results = {}
for metric_name, values in data.items():
mean = np.mean(values)
sem = stats.sem(values)
ci = stats.t.interval(
confidence,
len(values) - 1,
loc=mean,
scale=sem
)
results[metric_name] = {
"mean": mean,
"std": np.std(values),
"ci_lower": ci[0],
"ci_upper": ci[1],
"ci_width": ci[1] - ci[0]
}
return results
4.4 Visualization¶
Generate comparison visualizations:
import matplotlib.pyplot as plt
import seaborn as sns
def plot_comparison(baseline, sqlite, neo4j, metric_name):
"""Generate box plot comparison."""
data = pd.DataFrame({
'Control (No Memory)': baseline,
'SQLite Memory': sqlite,
'Neo4j Memory': neo4j
})
plt.figure(figsize=(10, 6))
sns.boxplot(data=data)
plt.ylabel(metric_name)
plt.title(f'{metric_name} Comparison Across Configurations')
plt.savefig(f'comparison_{metric_name}.png')
plt.close()
5. Baseline Establishment¶
5.1 Control Configuration Setup¶
class ControlConfiguration:
"""Configuration with no memory system."""
def __init__(self):
self.memory_enabled = False
self.agents = load_agent_definitions() # Standard agents
def run_scenario(self, scenario):
"""Run scenario without memory."""
# No memory retrieval
# No memory storage
# Pure agent execution
return run_agent_task(scenario, memory=None)
5.2 Baseline Data Collection¶
Process:
- Run all 10 scenarios × 5 iterations = 50 baseline runs
- Collect all metrics for each run
- Calculate baseline statistics (mean, std, CI)
- Save baseline data for comparison
Expected Results:
{
"baseline_statistics": {
"execution_time": {
"mean": 180.5,
"std": 25.3,
"ci_95": [175.2, 185.8]
},
"error_count": {
"mean": 3.2,
"std": 1.5,
"ci_95": [2.8, 3.6]
},
"quality_score": {
"mean": 7.5,
"std": 0.8,
"ci_95": [7.3, 7.7]
}
}
}
5.3 Baseline Documentation¶
Store baseline results in:
Include:
- Raw data (JSON format)
- Statistical summaries
- Scenario-specific performance
- Environmental context (machine specs, model version)
6. Test Harness Implementation¶
6.1 Architecture¶
scripts/memory_test_harness.py
├── Configuration Management
│ ├── ControlConfig (no memory)
│ ├── SQLiteConfig (SQLite memory)
│ └── Neo4jConfig (Neo4j memory)
├── Scenario Management
│ ├── ScenarioLoader (load scenario definitions)
│ ├── ScenarioRunner (execute scenarios)
│ └── ScenarioValidator (verify results)
├── Metrics Collection
│ ├── MetricsCollector (collect metrics)
│ ├── MetricsAggregator (aggregate across runs)
│ └── MetricsStorage (save to database)
├── Statistical Analysis
│ ├── StatisticalTests (t-tests, effect sizes)
│ ├── ConfidenceIntervals (calculate CIs)
│ └── MultipleComparisonsCorrection (Bonferroni)
└── Reporting
├── ReportGenerator (create comparison reports)
├── Visualization (generate plots)
└── SummaryExporter (export results)
6.2 Core Interface¶
# scripts/memory_test_harness.py
class MemoryTestHarness:
"""Automated A/B test harness for memory systems."""
def __init__(self, output_dir: str = "test_results"):
self.output_dir = Path(output_dir)
self.scenarios = self.load_scenarios()
self.configurations = {
"control": ControlConfiguration(),
"sqlite": SQLiteConfiguration(),
"neo4j": Neo4jConfiguration()
}
def run_full_test_suite(self):
"""Run complete A/B test suite."""
print("=" * 70)
print("MEMORY SYSTEM A/B TEST SUITE")
print("=" * 70)
# Phase 1: Baseline
print("\n[Phase 1] Establishing baseline (no memory)...")
baseline_results = self.run_configuration("control")
self.save_results(baseline_results, "baseline")
# Phase 2: SQLite
print("\n[Phase 2] Testing SQLite memory...")
sqlite_results = self.run_configuration("sqlite")
self.save_results(sqlite_results, "sqlite")
# Analyze Phase 2
comparison_2 = self.compare_configurations(baseline_results, sqlite_results)
self.save_comparison(comparison_2, "baseline_vs_sqlite")
if comparison_2["proceed_recommendation"]:
# Phase 3: Neo4j (only if Phase 2 successful)
print("\n[Phase 3] Testing Neo4j memory...")
neo4j_results = self.run_configuration("neo4j")
self.save_results(neo4j_results, "neo4j")
# Analyze Phase 3
comparison_3 = self.compare_configurations(sqlite_results, neo4j_results)
self.save_comparison(comparison_3, "sqlite_vs_neo4j")
# Phase 4: Final Analysis
print("\n[Phase 4] Generating final report...")
self.generate_final_report()
def run_configuration(self, config_name: str) -> List[dict]:
"""Run all scenarios for a configuration."""
config = self.configurations[config_name]
results = []
for scenario in self.scenarios:
print(f" Running scenario: {scenario.name}")
for iteration in range(5): # 5 iterations per scenario
print(f" Iteration {iteration + 1}/5...", end="")
# Run scenario
result = self.run_single_test(config, scenario, iteration)
results.append(result)
print(f" Done ({result['time']['total_execution']:.1f}s)")
return results
def run_single_test(
self,
config: Configuration,
scenario: Scenario,
iteration: int
) -> dict:
"""Run a single test iteration."""
# Initialize metrics collector
collector = MetricsCollector(scenario.id, config.name)
collector.start_collection()
# Run scenario with configuration
try:
output = config.run_scenario(scenario)
# Collect metrics from output
self.collect_metrics_from_output(collector, output)
except Exception as e:
# Record failure
collector.record_quality_metric("error_occurred", 1)
collector.record_quality_metric("error_message", str(e))
# Finalize and return metrics
return collector.finalize()
def compare_configurations(
self,
baseline: List[dict],
treatment: List[dict]
) -> dict:
"""Compare two configurations statistically."""
comparison = {}
# Extract metrics for comparison
metrics = ["execution_time", "error_count", "quality_score"]
for metric in metrics:
baseline_values = [r["time"]["execution_time"] if metric == "execution_time"
else r["quality"][metric] for r in baseline]
treatment_values = [r["time"]["execution_time"] if metric == "execution_time"
else r["quality"][metric] for r in treatment]
# Run statistical test
comparison[metric] = self.statistical_test(baseline_values, treatment_values)
# Determine recommendation
comparison["proceed_recommendation"] = self.should_proceed(comparison)
return comparison
def should_proceed(self, comparison: dict) -> bool:
"""Determine if results justify proceeding."""
# Check if improvement is statistically significant
significant = comparison["execution_time"]["significant"]
# Check if effect size is meaningful
effect_size = abs(comparison["execution_time"]["effect_size"])
meaningful = effect_size > 0.5 # Medium effect
# Check if p-value is strong
strong = comparison["execution_time"]["p_value"] < 0.01
return significant and meaningful
def generate_final_report(self):
"""Generate comprehensive comparison report."""
report = FinalReportGenerator(self.output_dir)
report.generate()
print(f"\n{'=' * 70}")
print(f"Final report saved to: {self.output_dir}/COMPARISON_RESULTS.md")
print(f"{'=' * 70}")
6.3 Scenario Definition Format¶
# scenarios/01_repeat_authentication.yaml
id: repeat_authentication
name: Repeat Authentication Implementation
type: learning_from_repetition
expected_benefit: high
iterations: 5
description: |
Implement JWT authentication for REST API.
First iteration: no memory, explores options.
Second iteration: should reuse proven pattern.
first_run:
task: "Implement JWT authentication for REST API with user login endpoint"
project: "test_project_auth_1"
expected_files:
- "auth/jwt_handler.py"
- "auth/user_model.py"
- "tests/test_auth.py"
success_criteria:
- "Tests pass"
- "JWT token generation works"
- "Token validation works"
second_run:
task: "Implement JWT authentication for REST API with user login endpoint"
project: "test_project_auth_2"
expected_files:
- "authentication/jwt.py"
- "models/user.py"
- "tests/test_jwt.py"
success_criteria:
- "Tests pass"
- "JWT token generation works"
- "Token validation works"
- "Reuses pattern from first run (memory)"
metrics:
primary:
- execution_time
- error_count
- pattern_reuse_detected
secondary:
- code_quality_score
- test_coverage
- documentation_completeness
7. Reporting Format¶
7.1 Comparison Report Structure¶
# Memory System Comparison Results
**Test Date**: 2025-11-03
**Configurations Tested**: Control, SQLite, Neo4j
**Total Test Runs**: 150 (50 per configuration)
## Executive Summary
### Key Findings
- **Memory Benefit**: [YES/NO] - Memory provides [X]% improvement over no memory
- **Neo4j Benefit**: [YES/NO] - Neo4j provides [X]% improvement over SQLite
- **Statistical Confidence**: [HIGH/MEDIUM/LOW] - p-value: [X], effect size: [X]
- **Recommendation**: [PROCEED/STOP/ADJUST]
### Performance Summary
| Metric | Control | SQLite | Neo4j | SQLite Δ | Neo4j Δ |
| ------------------ | ------- | ------ | ----- | -------- | -------- |
| Avg Execution Time | 180s | 120s | 115s | **-33%** | **-36%** |
| Avg Error Count | 3.2 | 1.5 | 1.2 | **-53%** | **-63%** |
| Avg Quality Score | 7.5 | 8.3 | 8.5 | **+11%** | **+13%** |
## Detailed Analysis
### 1. Execution Time
**Baseline (Control)**: 180.5s (±25.3s)
**SQLite**: 120.2s (±18.7s)
**Neo4j**: 115.3s (±17.2s)
**Statistical Test (Control vs SQLite)**:
- t-statistic: -12.34
- p-value: < 0.001 ✓ **Highly Significant**
- Effect size (Cohen's d): 0.82 (Large)
- 95% CI for difference: [-65.2, -55.4]s
**Interpretation**: SQLite memory reduces execution time by 33% with large effect size. This is a **substantial and statistically significant improvement**.
[... continue for each metric ...]
## Scenario-Specific Results
### Scenario 1: Repeat Authentication
- Control: 210s ± 30s
- SQLite: 95s ± 12s (**-55%**)
- Neo4j: 90s ± 11s (**-57%**)
- **Memory Impact**: Very High
[... continue for each scenario ...]
## Cost-Benefit Analysis
### Development Cost
- SQLite implementation: 3 weeks (1 FTE)
- Neo4j migration: +2 weeks (1 FTE)
### Expected Benefits
- Time saved per developer: 2-4 hours/week
- Error reduction: 50-70%
- Break-even: 4-6 weeks
### Recommendation
**PROCEED with SQLite implementation**
- Provides substantial benefit (33% time reduction)
- Statistically significant (p < 0.001)
- Justifies development investment
**DEFER Neo4j migration**
- Incremental benefit over SQLite is small (3%)
- Current scale doesn't justify complexity
- Revisit when >100k memory entries
7.2 Visualization Examples¶
Generate plots for report:
- Execution Time Comparison (box plot)
- Error Count Comparison (box plot)
- Quality Score Comparison (violin plot)
- Scenario-Specific Performance (grouped bar chart)
- Memory Hit Rate Over Time (line chart)
- Statistical Power Analysis (power curve)
8. Decision Criteria¶
8.1 Go/No-Go Decision Matrix¶
| Criteria | Threshold | Weight |
|---|---|---|
| Statistical Significance | p < 0.05 | Required |
| Effect Size | Cohen's d > 0.5 | Required |
| Practical Improvement | > 20% time reduction | High |
| Error Reduction | > 30% fewer errors | High |
| Quality Improvement | > 10% quality increase | Medium |
| Cost-Benefit Ratio | ROI > 0 within 6 months | High |
8.2 Decision Rules¶
Proceed with SQLite if:
- Statistical significance (p < 0.05) ✓
- Medium-to-large effect size (d > 0.5) ✓
- Practical benefit > 20% ✓
- No significant negative side effects ✓
Proceed with Neo4j if:
- Statistical significance vs SQLite (p < 0.05) ✓
- Meaningful improvement > 15% over SQLite ✓
- Complexity justified by benefit ✓
- Current scale warrants graph database (>100k nodes) ✓
Stop/Adjust if:
- No statistical significance (p > 0.05)
- Negligible effect size (d < 0.2)
- Negative impact on other metrics
- High false positive rate in memory retrieval
9. Limitations and Threats to Validity¶
9.1 Internal Validity Threats¶
- Learning Effects: Later iterations may benefit from agent "learning" independent of memory
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Mitigation: Randomize scenario order, use fresh agent instances
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Scenario Selection Bias: Chosen scenarios may favor memory systems
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Mitigation: Include diverse scenario types, some less memory-dependent
-
Metric Gaming: Agents may optimize for measured metrics
- Mitigation: Use multiple independent metrics, manual quality reviews
9.2 External Validity Threats¶
- Generalization: Test scenarios may not represent all real-world usage
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Mitigation: Select scenarios based on user research, validate with users
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Scale: Test scale (50 runs) may not reflect production scale
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Mitigation: Run longer-term trials after initial validation
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Environment: Controlled test environment differs from real usage
- Mitigation: Follow up with in-situ testing with real users
9.3 Construct Validity Threats¶
- Metric Validity: Measured metrics may not capture all aspects of quality
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Mitigation: Combine automated metrics with expert review
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Memory Quality: Test may not assess memory correctness (false positives)
- Mitigation: Manual review of memory retrieval accuracy
10. Implementation Timeline¶
Week 1: Test Harness Development¶
- Day 1-2: Design test harness architecture
- Day 3-5: Implement core harness functionality
- Weekend: Review and refinement
Week 2: Scenario Implementation¶
- Day 1-2: Implement 5 scenarios
- Day 3-4: Implement remaining 5 scenarios
- Day 5: Validate scenarios, dry runs
Week 3: Baseline Testing¶
- Day 1-3: Run baseline tests (Control configuration)
- Day 4: Analyze baseline results
- Day 5: Document baseline, prepare for Phase 2
Week 4: SQLite Testing¶
- Day 1-3: Run SQLite memory tests
- Day 4: Statistical analysis, comparison to baseline
- Day 5: Phase 2 decision gate meeting
Week 5: Neo4j Testing (if Phase 2 successful)¶
- Day 1-3: Run Neo4j memory tests
- Day 4: Statistical analysis, comparison to SQLite
- Day 5: Generate final report
Week 6: Analysis and Reporting¶
- Day 1-2: Comprehensive analysis
- Day 3-4: Create visualizations, write report
- Day 5: Present findings, make final decision
Total Duration: 6 weeks (assuming no major issues)
11. Success Criteria¶
Minimum Success Criteria (Required)¶
- ✓ Statistical significance (p < 0.05)
- ✓ Medium effect size (d > 0.5)
- ✓ Practical improvement (>20% time reduction)
- ✓ No major negative side effects
Stretch Success Criteria (Desired)¶
- ✓ Large effect size (d > 0.8)
- ✓ Strong significance (p < 0.01)
- ✓ Error reduction >50%
- ✓ Quality improvement >15%
- ✓ Positive user feedback
12. Risk Mitigation¶
Risk 1: Insufficient Sample Size¶
Mitigation: Run additional iterations if initial results show high variance
Risk 2: Confounding Variables¶
Mitigation: Strictly control environment, document all variables
Risk 3: Test Harness Bugs¶
Mitigation: Extensive testing of harness before main test runs
Risk 4: Long Test Duration¶
Mitigation: Parallelize test runs where possible, use automation
Conclusion¶
This A/B test design provides a rigorous, fair, and scientifically sound methodology for evaluating memory system effectiveness. Key strengths:
- Three-way comparison: Control, SQLite, Neo4j
- Statistical rigor: Proper sample sizes, multiple tests correction
- Fair comparison: Controlled variables, randomization
- Practical focus: Measures what matters (time, errors, quality)
- Phased approach: Decision gates prevent over-investment
Next Steps:
- Review and approve design
- Implement test harness (Week 1-2)
- Run baseline tests (Week 3)
- Make data-driven decisions at each gate
Document Status: ✅ Design Complete - Ready for Implementation Author: Architect Agent Review Date: 2025-11-03