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