{ "evaluation_id": "EVAL-20260402-190115", "question_id": "ANALYSIS-005", "question_text": "Your team ran an A/B test on a checkout flow. Here are the results:\n\nControl (A): 10,000 visitors, 320 conversions (3.2%)\nTreatment (B): 10,000 visitors, 380 conversions (3.8%)\n\nThe product manager says: \"B wins! Let's ship it - that's an 18.75% improvement!\"\n\n1. Calculate the statistical significance (provide p-value)\n2. What's the 95% confidence interval for the true difference?\n3. The test ran for 2 days. What concerns does this raise?\n4. You discover Treatment B had a bug on iOS that blocked 2,000 users from even reaching checkout. How does this change your analysis?\n5. What would you recommend?", "category": "analysis", "timestamp": "2026-02-12T00:00:00.000Z", "display_date": "Feb 12, 2026", "winner": { "name": "GPT-5.4", "provider": "openrouter", "score": 9.3 }, "avg_score": 7.841111, "matrix_size": 81, "models_used": [ { "id": "claude_opus_46", "name": "Claude Opus 4.6", "provider": "openrouter" }, { "id": "gpt_5_4", "name": "GPT-5.4", "provider": "openrouter" }, { "id": "deepseek_v4", "name": "DeepSeek V4", "provider": "openrouter" }, { "id": "mimo_v2_flash", "name": "MiMo-V2-Flash", "provider": "Xiaomi" }, { "id": "claude_sonnet_46", "name": "Claude Sonnet 4.6", "provider": "openrouter" }, { "id": "grok_420", "name": "Grok 4.20", "provider": "openrouter" }, { "id": "gpt_oss_120b", "name": "GPT-OSS-120B", "provider": "OpenAI" }, { "id": "gemini_3_flash", "name": "Gemini 3 Flash Preview", "provider": "Google" }, { "id": "gemini_31_pro", "name": "Gemini 3.1 Pro", "provider": "openrouter" } ], "rankings": { "gpt_5_4": { "display_name": "GPT-5.4", "provider": "openrouter", "average_score": 9.3, "score_count": 9, "min_score": 8.8, "max_score": 10, "rank": 1 }, "claude_sonnet_46": { "display_name": "Claude Sonnet 4.6", "provider": "openrouter", "average_score": 8.97, "score_count": 9, "min_score": 7.75, "max_score": 9.8, "rank": 2 }, "grok_420": { "display_name": "Grok 4.20", "provider": "openrouter", "average_score": 8.84, "score_count": 9, "min_score": 7.7, "max_score": 9.8, "rank": 3 }, "claude_opus_46": { "display_name": "Claude Opus 4.6", "provider": "openrouter", "average_score": 8.63, "score_count": 9, "min_score": 6.65, "max_score": 9.8, "rank": 4 }, "gemini_3_flash": { "display_name": "Gemini 3 Flash Preview", "provider": "Google", "average_score": 8.52, "score_count": 9, "min_score": 6.5, "max_score": 9.35, "rank": 5 }, "mimo_v2_flash": { "display_name": "MiMo-V2-Flash", "provider": "Xiaomi", "average_score": 8.49, "score_count": 9, "min_score": 6.8, "max_score": 9.8, "rank": 6 }, "deepseek_v4": { "display_name": "DeepSeek V4", "provider": "openrouter", "average_score": 8.19, "score_count": 9, "min_score": 6.1, "max_score": 9.8, "rank": 7 }, "gpt_oss_120b": { "display_name": "GPT-OSS-120B", "provider": "OpenAI", "average_score": 7.14, "score_count": 9, "min_score": 4.55, "max_score": 8.45, "rank": 8 }, "gemini_31_pro": { "display_name": "Gemini 3.1 Pro", "provider": "openrouter", "average_score": 2.49, "score_count": 9, "min_score": 1.2, "max_score": 6, "rank": 9 } }, "judgments": [ { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 8.15, "brief_justification": "The mathematical calculations and analytical reasoning are excellent and highly detailed. However, the response cuts off abruptly mid-sentence and completely fails to answer the final question regarding recommendations, significantly reducing its completeness and overall usefulness." }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 10, "brief_justification": "" }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 7.2, "brief_justification": "" }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 7.15, "brief_justification": "" }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 9.05, "brief_justification": "" }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 8.55, "brief_justification": "" }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 5.5, "brief_justification": "The mathematical calculations for parts 1 and 2 are highly accurate and clearly presented. However, the response cuts off abruptly, completely failing to answer parts 3, 4, and 5, resulting in poor completeness, depth, and usefulness." }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 6.5, "brief_justification": "" }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 1.65, "brief_justification": "The response is severely incomplete - it cuts off after barely starting the first of five questions. Only the beginning of the statistical significance calculation is shown, with no p-value computed, no confidence interval, no discussion of the 2-day concern, no analysis of the iOS bug, and no recommendation. It cannot be considered a meaningful answer to the multi-part question." }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 9.75, "brief_justification": "The response is exceptionally thorough and well-structured. The statistical calculations are correct (pooled proportion, z-statistic, p-value, confidence interval all check out). The analysis of the 2-day concern is comprehensive, covering day-of-week effects, novelty, peeking, and conversion windows. The iOS bug analysis is particularly impressive, distinguishing between ITT and treatment-on-the-treated estimands, explaining how aggregate results can mask segment-level harm, and correctly notin" }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 8.75, "brief_justification": "The statistical calculations are largely correct (z-score ~2.31, p-value ~0.021, CI approximately right). One minor issue: the CI calculation should technically use unpooled SE rather than the pooled SE used for the hypothesis test, but the difference is negligible here. The analysis of the iOS bug is well-reasoned, correctly identifying that the effective denominator changes and the conversion rate is actually higher for eligible users. The concerns about 2-day duration are comprehensive. The r" }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 8.95, "brief_justification": "The statistical calculations are largely correct: the z-test, pooled proportion, SE, z-score (~2.31), and p-value (~0.01 one-tailed) are all accurate. The CI calculation is reasonable, though technically the unpooled SE should be used for the CI (a minor methodological point). The analysis of the iOS bug is well-reasoned—correctly identifying that the 2,000 blocked users should be excluded from the denominator and recalculating the conversion rate. The concerns about the 2-day test duration are " }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 9.2, "brief_justification": "The statistical calculations are accurate (z≈2.31, p≈0.021, CI correctly computed). The analysis of the 2-day duration concerns is thorough and well-reasoned, covering novelty effects, day-of-week bias, and the peeking problem. The iOS bug analysis is excellent — correctly recalculates the effective conversion rate (4.75%), identifies the sample ratio mismatch, and explains why the test is invalidated. The recommendation is practical and actionable with a clear framework. Minor issues: the power" }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 9.35, "brief_justification": "The statistical calculations are accurate (z≈2.31, p≈0.021, CI correctly computed). The analysis of the 2-day runtime concerns is thorough and well-reasoned. The iOS bug analysis is excellent—correctly identifying it as invalidating the test, providing a reasonable adjusted estimate, and noting the bias implications. The recommendation is practical, actionable, and appropriately cautious. Minor nit: the adjusted analysis could note that the 380 conversions came from 8,000 eligible users (4.75% r" }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 6.95, "brief_justification": "The statistical calculations in parts 1 and 2 are correct and clearly presented (p≈0.021, CI correctly computed). However, the response is clearly truncated - parts 3, 4, and 5 are missing or incomplete. Part 3 about the 2-day test concerns starts a table but cuts off. Parts 4 (iOS bug analysis) and 5 (recommendation) are entirely absent. These are arguably the most important parts of the question, testing analytical thinking and practical judgment. The math that is present is accurate and well-" }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 8.95, "brief_justification": "The statistical calculations are close to correct (p-value ~0.021 is reasonable, z-score ~2.31 checks out, CI is approximately right). The analysis of the 2-day duration concerns, iOS bug implications, and recommendations are thorough, well-structured, and actionable. Minor nit: the SE calculation intermediate steps could be slightly more precise, and the CI bounds could be stated more precisely, but overall this is an excellent, well-organized response that demonstrates strong analytical thinki" }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 1.2, "brief_justification": "The response is truncated and incomplete. It only begins to mention a two-proportion z-test without providing the p-value, confidence interval, discussion of test duration concerns, impact of the iOS bug, or a recommendation." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 6.65, "brief_justification": "Good statistical calculations for p-value and CI, and strong discussion of runtime concerns and bug-induced selection bias. However, the response is incomplete/cut off before finishing the iOS bug analysis and recommendation, and some claims (like specific alpha inflation from peeking) are asserted without support." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 6.1, "brief_justification": "Clear structure and mostly correct initial z-test/p-value, but the confidence interval is computed with the wrong SE and the iOS bug analysis is materially flawed: blocked users should not be excluded from the denominator if analyzing end-to-end checkout conversion, and calling the original rate inflated is incorrect. Recommendations are directionally reasonable but weakened by the bug misinterpretation." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 7.7, "brief_justification": "Clear and mostly thorough, with solid discussion of duration and recommendation. Main issue is the iOS bug analysis: excluding blocked users and calling 4.75% the 'true' treatment effect is not valid for the original randomized experiment; intent-to-treat should be emphasized, with segment/debug analysis separated from overall rollout impact. Minor concern that the reported p-value defaults to one-tailed without justification." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 7.75, "brief_justification": "Statistical calculations are largely correct and the recommendation is sensible. Strong discussion of short test duration and experiment integrity. Main issue: the iOS bug analysis overstates certainty by treating 380/8000 as the 'true' treatment rate and mislabels the situation as SRM; this is more an instrumentation/eligibility problem and the adjusted comparison requires stronger assumptions. The response is also truncated at the end." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 7.7, "brief_justification": "Statistical test and CI are essentially correct and clearly explained, with good discussion of short-duration risks and a sensible recommendation. However, the iOS bug analysis is flawed: it inconsistently treats denominators/effective visitors, proposes an ad hoc adjustment, and misses the key intent-to-treat vs exposure-analysis distinction, so correctness is materially reduced." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 4.55, "brief_justification": "The p-value and CI calculations are essentially correct, but the response is incomplete: it stops midway through part 3 and does not address the iOS bug analysis or final recommendation. Structure is clear up to the cutoff, but overall coverage and practical usefulness are limited." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 8.55, "brief_justification": "Accurate p-value and CI with clear interpretation, strong discussion of short test-duration risks, and sensible recommendation not to ship. Main weakness is the iOS bug analysis: it correctly flags invalidity but is somewhat ambiguous about denominators and does not fully quantify the revised impact or explicitly distinguish intent-to-treat vs reachable-checkout analysis." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 6, "brief_justification": "Incomplete response with missing calculations and analysis, but structure is clear." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 8.8, "brief_justification": "Highly accurate and thorough analysis with insightful depth and practical recommendations." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 8.8, "brief_justification": "Detailed and accurate analysis with practical recommendations." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 9, "brief_justification": "Detailed, accurate, and actionable analysis with clear explanations." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 9.55, "brief_justification": "Highly accurate, thorough, and actionable with excellent depth and clarity." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 9, "brief_justification": "Accurate calculations, thorough analysis, clear structure, insightful depth, and highly actionable recommendations." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 8.45, "brief_justification": "Accurate calculations and clear explanations, though slightly incomplete on concerns and recommendations." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 9.2, "brief_justification": "Accurate calculations, thorough analysis, clear structure, insightful concerns, and actionable recommendations." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 2.2, "brief_justification": "The response is incomplete and cuts off mid-calculation. It fails to answer the majority of the prompt, including the p-value, confidence interval, time concerns, bug impact, and recommendations." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 9.55, "brief_justification": "Accurate statistical calculations, thorough coverage of all questions, clear structure, insightful analysis of bias and bug implications, and highly actionable recommendations." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 9, "brief_justification": "The response is highly accurate, covering all aspects of the question with strong statistical rigor and practical product sense. It correctly calculates significance and CI, identifies critical test duration risks, and provides a nuanced analysis of the iOS bug's impact on validity and interpretation. Recommendations are actionable and well-reasoned." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 8.35, "brief_justification": "Accurate statistical calculations and solid recommendations. Minor deduction for not explicitly mentioning the need to check if the 380 conversions include the blocked iOS users, but the overall analysis is robust and actionable." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 9, "brief_justification": "Excellent statistical analysis, correctly identifies the SRM and invalidates the test, provides actionable recommendations." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 9.35, "brief_justification": "Accurate statistical calculations, thorough coverage of all questions, clear structure, insightful analysis of bug impact and test validity, and highly actionable recommendations." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 7.35, "brief_justification": "Statistical calculations are accurate and well-explained, but the response is incomplete (cuts off mid-sentence) and misses the bug analysis and recommendation." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 9.35, "brief_justification": "The response is mathematically accurate (p-value, CI), covers all sub-questions thoroughly, and provides highly actionable recommendations. It correctly identifies the statistical nuances and the severe impact of the iOS bug." }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 1.45, "brief_justification": "The response is severely truncated and incomplete. It begins the analysis but cuts off mid-sentence after barely starting point 1. None of the five questions are answered. The fragment shown appears methodologically correct (two-proportion z-test is appropriate), but the response fails to deliver any actual calculations, p-values, confidence intervals, or recommendations. This is essentially a non-answer." }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 9.2, "brief_justification": "Exceptionally thorough analysis with correct statistical calculations (z-test, p-value ~0.021, CI), strong identification of the iOS bug's dual interpretations (selection bias vs. true lift), and excellent coverage of temporal concerns like novelty effects and peeking. The response is well-structured and actionable. Minor deduction for the response appearing to be cut off before completing the iOS analysis and recommendation sections, but what's present is high quality." }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 9.35, "brief_justification": "Excellent response covering all five questions thoroughly. Statistical calculations are correct (pooled SE, z-stat ~2.31, p-value ~0.021, CI ~0.09-1.11pp). The iOS bug analysis is particularly strong, distinguishing ITT vs treatment-on-treated, explaining how aggregate results can mask segment-level damage. Recommendations are actionable and well-prioritized. Minor note: the relative lift CI calculation is slightly informal but directionally correct. The response demonstrates strong statistical " }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 8.55, "brief_justification": "The response correctly performs the two-proportion z-test with accurate calculations (z≈2.31, p≈0.021), provides the CI correctly, and addresses all five questions thoroughly. The iOS bug analysis is insightful but slightly misframes the issue - the bug blocked users from reaching checkout entirely, meaning those 2,000 users shouldn't be in the denominator at all (they never saw the treatment), making the corrected rate interpretation reasonable. The concerns about 2-day testing are well-articul" }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 9.2, "brief_justification": "Excellent response covering all five questions with proper statistical calculations, correct z-test methodology, accurate p-value and CI calculations, thoughtful concerns about test duration, and insightful analysis of the iOS bug impact. The recommendation is practical and well-reasoned. Minor note: the CI uses the pooled SE rather than unpooled SE (which is more standard for CIs), but this is a minor methodological point that doesn't significantly affect the result. The iOS bug analysis is par" }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 8.8, "brief_justification": "Excellent response with accurate statistical calculations (z-test, p-value ~0.021, correct CI), thorough coverage of all five questions, and clear actionable recommendations. The iOS bug analysis is particularly strong, noting selection bias and attempting an adjusted estimate. Minor quibble: the relative lift CI calculation isn't shown explicitly, but the absolute CI is correct. The recommendation to not ship is well-justified and practical." }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 8.1, "brief_justification": "The statistical calculations are accurate and well-presented - correct pooled proportion, SE, z-statistic (2.31), p-value (~0.021), and confidence interval. The unpooled SE calculation is slightly off (the two variances don't quite equal 3.10e-6 and 3.66e-6 but the final answer is reasonable). The response appears truncated, cutting off at question 3's table and missing questions 4 and 5 entirely, which significantly impacts completeness and usefulness scores. The portions that are present show " }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 8.55, "brief_justification": "The analysis is thorough and well-structured. The p-value calculation is correct (~0.021), the CI is accurately computed [0.09%, 1.11%], and the concerns about test duration are well-articulated. The iOS bug analysis is insightful, correctly identifying selection bias. Minor issue: the response could more explicitly quantify how the iOS bug changes the effective sample size and recalculate metrics. The recommendation is practical and actionable. Overall an excellent response that goes beyond sur" }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 3.65, "brief_justification": "The response is incomplete, abruptly cut off mid-sentence after starting the first point. While it correctly identifies the two-proportion z-test, it provides no actual calculations, p-value, confidence interval, or answers to the other questions. This fails to address the full query." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 8.85, "brief_justification": "Highly accurate calculations (p-value, CI, SE), comprehensive coverage of all questions with strong statistical and practical insights. Minor approximation in p-value (actual ~0.021) and slight SE rounding, but overall rigorous and actionable." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 9, "brief_justification": "Response is factually accurate with correct statistical calculations (p≈0.021, CI roughly matches), thorough coverage of all 5 questions including practical concerns, clearly structured with equations and lists, provides insightful analysis on validity threats like bugs and short duration, and offers actionable recommendations." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 8.4, "brief_justification": "Accurate calculations and solid statistical approach with good explanations; minor approximation in SE and p-value but overall correct. Comprehensive coverage of all points with practical recommendations." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 6.8, "brief_justification": "The response provides mostly correct calculations and good insights on concerns, but contains errors in handling the bug: incorrectly excludes blocked users from denominator without adjusting conversions properly, leading to invalid 4.75% rate and flawed stats. CI and p-value are reasonable but SE is slightly miscalculated. Recommendations are practical." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 8.6, "brief_justification": "The response is factually accurate on calculations (p-value ~0.021, CI correct), logically sound, and thorough. It covers all questions with insightful analysis on biases, SRM, and practical implications. Minor nit: the CI is presented in percentage points but labeled with confusing relative lift bounds; the iOS adjustment assumes equal rates without full data. Overall very high quality." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 7.9, "brief_justification": "The response provides accurate calculations for p-value and CI with correct formulas and values. It is clear and structured. However, it is incomplete as it only addresses parts 1 and 2, stopping mid-table in part 3, and does not cover parts 4 or 5 at all." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 8.55, "brief_justification": "Calculations are mostly accurate (p-value and CI close to standard results), analysis is thorough and well-structured with good insights on biases and practical concerns. Minor rounding/notation issues in CI but overall high quality." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 2, "brief_justification": "Response is truncated and fails to provide p-value, confidence interval, discussion of concerns, bug impact, or recommendation, making it largely incorrect and incomplete." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 7.7, "brief_justification": "Accurate statistical calculations and solid discussion of timing and bias issues, but the answer stops short of a full bug impact analysis and omits a concrete recommendation, reducing completeness and overall usefulness." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 8.8, "brief_justification": "Accurate calculations, thorough coverage of all questions, clear structure, good analytical depth, and actionable recommendations." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 7.8, "brief_justification": "Accurate statistical calculations and clear explanations, but misinterprets the impact of the iOS bug on conversion rates and doesn't recompute significance, reducing overall correctness and depth." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 8.8, "brief_justification": "Accurate calculations and CI, thorough coverage of concerns, clear formatting, insightful discussion of bug impact and test duration, and practical recommendations." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 8.8, "brief_justification": "Accurate statistical calculations, thorough coverage of all questions, clear structure, insightful discussion of test duration and bug impact, and actionable recommendations." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 8.25, "brief_justification": "Accurate calculations and solid CI; addresses test duration concerns and bug impact with reasonable adjustments; clear layout and actionable recommendations, though bug analysis could explore more nuanced bias handling." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 8.25, "brief_justification": "Accurate statistical calculations and clear explanations; addresses all parts with practical recommendations. Could include more detailed reanalysis of the iOS bug impact and power considerations for greater depth." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 2.85, "brief_justification": "The response is incomplete and cuts off mid-sentence in the first section. It fails to answer four out of the five questions asked." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 9.8, "brief_justification": "The response is exceptionally high quality. It correctly calculates the p-value and confidence interval, provides a sophisticated analysis of the 2-day runtime (including novelty effects and peeking risk), and correctly identifies the selection bias introduced by the iOS bug. The use of visual aids and clear formatting makes the complex statistical concepts very accessible." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 10, "brief_justification": "The response is exceptionally thorough and accurate. It correctly calculates the p-value and confidence intervals, provides a sophisticated analysis of the 2-day duration risks (including novelty effects and day-of-week bias), and offers a nuanced interpretation of the iOS bug using ITT principles. The recommendations are practical and professional." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 9.8, "brief_justification": "The response is mathematically accurate, provides the correct p-value and confidence intervals, and offers a sophisticated analysis of the experimental flaws (novelty effect, selection bias, and technical bugs)." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 9.8, "brief_justification": "The response is exceptionally thorough and accurate. It correctly calculates the p-value and confidence interval, identifies the critical issues with a 2-day test duration (seasonality and novelty), and provides a sophisticated analysis of the iOS bug by recalculating the conversion rate for eligible users. The recommendation is practical and professional." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 9.8, "brief_justification": "The response is exceptionally thorough and accurate. It correctly calculates the p-value and confidence interval, provides a sophisticated analysis of the 2-day duration (mentioning the peeking problem and business cycles), and correctly identifies the Sample Ratio Mismatch (SRM) caused by the iOS bug. The recommendation is professional and includes a power analysis for the retest." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 9.8, "brief_justification": "The response is exceptionally accurate and thorough. It correctly calculates the p-value and confidence interval, identifies the critical statistical pitfalls of short-duration testing (day-of-week bias, novelty effect), and provides a sophisticated analysis of the selection bias introduced by the iOS bug. The recommendation is practical and professionally sound." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 8.25, "brief_justification": "The statistical calculations (p-value and confidence interval) are accurate and well-explained. However, the response is cut off at the beginning of section 3, failing to address the concerns about the 2-day duration, the iOS bug, or the final recommendation." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 1.45, "brief_justification": "Response is severely incomplete - cuts off mid-sentence after starting first calculation. No p-value provided, no confidence interval calculated, no discussion of 2-day duration concerns, no analysis of iOS bug impact, and no recommendations given." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 9, "brief_justification": "Excellent statistical analysis with correct p-value (~0.021) and confidence interval calculations. Thoroughly addresses all 5 questions including runtime concerns and iOS bug implications. Clear explanations with good visualizations. Depth shows nuanced understanding of selection bias and multiple testing issues. Highly actionable recommendations." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 9, "brief_justification": "Excellent response with accurate statistical calculations (p-value ~0.021, CI 0.09-1.11pp), comprehensive coverage of all five questions, clear well-structured explanations, deep analytical insights (ITT vs treatment effects, segment analysis, practical significance), and highly actionable recommendations (fix bug, segment analysis, rerun test). Only minor room for improvement would be mentioning sample ratio mismatch checks explicitly in the initial analysis." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 8.8, "brief_justification": "Statistically sound analysis with correct p-value (~0.021) and confidence interval calculations. All five questions thoroughly addressed with clear explanations. The bug analysis correctly identifies selection bias and recalculates the conversion rate. Recommendations are practical and actionable. Minor扣分 for not discussing effect size interpretation more fully." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 9, "brief_justification": "Accurate statistical calculations with proper z-test and confidence interval. Thoroughly addresses all 5 questions including important considerations about test duration and the iOS bug. Well-structured with clear explanations and formulas. Provides insightful depth on seasonality, SRM, and proper handling of the bug (excluding blocked users from denominator). Actionable recommendations that correctly advise against shipping until the bug is fixed and the test is rerun with proper duration." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 9, "brief_justification": "Excellent response with accurate statistical calculations (p-value ~0.021, CI of +0.09pp to +1.11pp), thorough analysis of all 5 questions, clear structured formatting, deep insights on the peeking problem, novelty effects, and sample ratio mismatch, and highly actionable recommendations including power analysis for retest." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 8.8, "brief_justification": "Accurate statistical calculations (p-value, CI), comprehensive coverage of all five questions, well-organized with clear formatting, good depth on test duration concerns and bug analysis with adjusted calculations, and actionable recommendations (fix bug, retest, segment analysis)." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 7.2, "brief_justification": "Statistical calculations are accurate and well-presented with clear formulas. However, response is severely incomplete - cuts off mid-answer for question 3 and completely omits questions 4 (iOS bug analysis) and 5 (recommendations), significantly reducing overall usefulness." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 8.8, "brief_justification": "Thorough analysis covering all five questions with accurate statistical calculations, valid concerns about test duration, and insightful analysis of the iOS bug's impact. Clear structure and actionable recommendations. Minor depth deduction for not explicitly mentioning power analysis or checking assumptions of the z-test." } ], "meta": { "source": "The Multivac (app.themultivac.com)", "methodology": "10x10 blind peer matrix evaluation", "criteria": "correctness, completeness, clarity, depth, usefulness", "self_judgments": "excluded from rankings", "license": "Open data — cite as: The Multivac (2026)" } }