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Research

AI, Equity, and the Statistics Classroom

Four studies on how instruction, technology, and policy shape who succeeds in college mathematics, each with every claim scoped to what its design can support.

2 under review2 preprints
IPlacement & EquityUnder Review

Rising Success, Persistent Gaps

Community College Review (SAGE) · student-level analysis, 2018 to 2025

When California placed students directly into transfer-level statistics under AB 705 and AB 1705, did outcomes rise or fall, and did they improve equitably across groups?

Design & Data
  • 867 enrollments (852 students; 1.7% repeat), 17 semesters, Fall 2018 to Fall 2025
  • A single instructor at one large, diverse California community college
  • Enrollment-level logistic regression with semester-clustered SEs; Spearman rank trend; composition-adjusted robustness checks
Key Results
  • Course success rose 42% → 69% across the reform era (pre-AB705 42% → AB705 49% → post 59% → AB1705 69%)
  • Odds of passing +10% per semester (OR 1.10, 95% CI [1.07, 1.13]); Spearman ρ = 0.61, p = .009
  • Success rose for every group (White 69→84%, Latinx 44→61%, Black 27→62%, Asian 61→73%)
  • White and Latinx gap held at ~24 points; race×time interactions underpowered
What It Shows

Direct placement was associated with rising, not eroding, statistics success, contradicting the premise that removing remediation depresses outcomes. But broadened access alone did not close racial gaps.

Stated Limitation

A single-instructor design makes the temporal trend correlational: it cannot separate the reforms from the instructor's own growth over the same period. Reported as such throughout.

IIAI in TeachingRevise & Resubmit

AI-Assisted Assessment Design

Teaching Statistics · a multi-course Bloom's taxonomy analysis

Does designing exams with AI change the cognitive demand of what we ask students, and if so, in which direction?

Design & Data
  • Bloom's revised taxonomy; matched pre-AI vs. AI-assisted final exams, coded item by item
  • Two courses, same instructor: intro statistics (Winter 2025 vs. 2026; 34 vs. 25 MC items) and college algebra (Spring 2025 vs. 2026)
Key Results
  • Statistics: higher-order (Analyse) items 18% → 48% (+30 pts); procedural (Apply) 47% → 28% (−19 pts)
  • Student performance did not decline on the more demanding exam
  • Three Universal Design for Learning features appeared only in the AI version
  • Algebra: cognitive profile stable (85% Apply); AI showed in structure; mean final 61.8% → 78.7%
What It Shows

AI-assisted design works as an amplification mechanism: it lets instructors act on assessment-design intentions that severe time constraints had made impractical, not a replacement for instructor judgment.

Method Contribution

The paired-Bloom's analysis of matched pre- and post-AI exams is replicable across courses, instructors, and institutions, a portable way to audit whether AI raises or lowers the demand of assessments.

IIIDistributional EffectsPreprint

Raising the Floor, Holding the Bar

EdArXiv preprint · DOI 10.35542/osf.io/x9nkw_v1

When an instructor redesigns a course with AI, who moves, and where in the grade distribution does the change happen?

Design & Data
  • Official gradebook records, N = 106; four sections, two courses, same instructor
  • Quantile decomposition (10th to 90th percentiles); Holm family-wise error control across ten comparisons
  • Welch t & Mann-Whitney; Hedges g; percentile bootstrap (10,000); Lee-style trimming bound; attendance-adjusted ANCOVA
Key Results
  • Algebra final +16.9 pts (p = .004, Hedges g = 0.75), a floor effect
  • 10th percentile 22 → 58 (+36); share below 50% 31% → 5%; 90th percentile essentially unchanged
  • Statistics: performance maintained on a harder instrument
  • Alignment decides value: AI-aligned quizzes stayed predictive of the final; item-bank quizzes lost it
What It Shows

Means hide the students open-access colleges most need to see. AI-assisted design lifted the lowest performers most, and whether formative work keeps its diagnostic value depends on how well it aligns with the redesigned exam.

Stated Limitation

Small cells; unproctored scores inflated toward the ceiling. Effects are reported distributionally and per course before pooling, a reporting discipline this literature still lacks.

IVMethodological RangePreprint

Disadvantage, Not Policy or Illness, and Mass-Shooting Rates

Research Square preprint · a negative-binomial state panel, 2018 to 2024

Which state characteristics track mass-shooting rates, gun policy, mental illness, or socioeconomic conditions?

Design & Data
  • State-year panel: 50 states, 350 state-years, 3,783 incidents (Gun Violence Archive, 2018 to 2024)
  • Negative-binomial regression with population offset, calendar-year fixed effects, CR2 cluster-robust SEs
  • Standardized incidence-rate ratios per SD; LASSO + tree-ensemble triangulation
Key Results
  • Incidence roughly doubled at the 2021 peak (IRR 2.02, CI 1.68 to 2.43), elevated through 2024 (1.55)
  • Poverty IRR 1.45 [1.18 to 1.79], p = .006, the most stable predictor; inequality 1.44 (r = 0.50 with poverty)
  • Gun-law strength 1.11, ownership 1.07, serious mental illness 1.04, none associated
  • LASSO retained only the socioeconomic-disadvantage measures
What It Shows

The post-2020 surge was broad and sustained, and its geography tracks socioeconomic disadvantage, chiefly poverty, rather than gun-law permissiveness or mental-illness prevalence.

Stated Limitation

Ecological and observational: no individual-level or causal inference, and the conclusions are sensitive to how “mass shooting” is defined (here, the GVA four-or-more definition).