Data-Processing Multiverse Analysis of the Regnerus Study and Its Critics
Study Background and Context
- Focus of chapter: comprehensive multiverse re-analysis of Mark Regnerus’s 2012 study on outcomes of children raised by gay/lesbian parents (LGBT parents).
- Original article appeared in Social Science Research and became pivotal in legal and public debates (e.g., US Supreme Court cases on same-sex adoption).
- Chapter’s purpose: illustrate how data-processing “researcher degrees of freedom” can rival (or exceed) the impact of control-variable choices.
- Two multiverse analyses are constructed:
- Control-Variable Multiverse (11 possible controls → 211=2,048 models)
- Data-Processing Multiverse (combined with controls → (\approx 2.65) million models)
- Central questions examined:
- How much result variability comes from selecting control variables?
- How much comes from decisions about cleaning, coding, weighting, or defining key variables?
Original Regnerus Study (2012a)
- Dataset: New Family Structures Study (NFSS)
- 15,000 initial screen; 2,988 full surveys; 236 identified a parental same-sex relationship.
- Key screening question: “Did either of your parents ever have a romantic relationship with someone of the same sex?” (Mother/Father/No).
- Baseline regression (Eq. 11.1):
y{ij}=\beta0+\beta1\,\text{lesbian_mother}i+\beta2\,\text{gay_father}i+\sum{k=3}^4 \betak\,\text{other_family_type}{ik}+ \gamma'\,\text{controls}{ij}+\epsilon_{ij}
- 40 separate dependent variables (education, mental health, civic engagement, etc.) → 80 LGBT coefficients.
- Reported findings: children of LGBT parents worse on many outcomes (e.g., unemployment, public assistance, drug abuse, suicidal ideation).
- Control set: age, mother’s education, origin-family income, female, white, bullied-as-child (+ state gay-friendly score unavailable in public data).
- Cheng & Powell (2015)
- Added 5 controls (parents’ age at birth, region, metro status, childhood welfare receipt).
- Flagged extensive misclassification + “prankster” responses; argued 44 % of LGBT cases unreliable.
- Rosenfeld (2015)
- Combined 19 outcomes into a signed index; emphasized family transitions instead of Regnerus categories; rejected “bullied” as endogenous.
- Sherkat (2012) external review considered retraction; highlighted absence of data cleaning.
Multiverse Analysis Framework
Control-Variable Multiverse (2,048 models)
- 11 potential covariates (6 Regnerus + 5 critics) toggled on/off.
- Empirical pattern:
- All 2,048 coefficients negative and significant.
- Mean coefficient βˉ=−1.0; modeling SE ≈0.09 (smaller than sampling SE 0.16).
- Regnerus six-control model sits on low-magnitude side of distribution.
- Conclusion: control choice alone barely affects inference.
Data-Processing Multiverse (>2.6 M models)
- Dimensions added to the 2,048 control choices:
- Treatment of anomalous/outlier cases (4 options).
- Family-type operationalisation (6 options).
- Outcome-index construction (2 options).
- Weighting strategy (weighted vs. unweighted).
- Winsorising outcomes (yes/no).
- Alternative codings of income, age, race, mother’s education (4,3,3,3 options).
- Total ≈ 2,654,208 unique specifications.
Key Data-Processing Decisions & Rationale
Anomalous Observations
- Evidence of prank responses: e.g., 7’8” tall, 88 lb respondent; 10 pregnancies; 100+ sexual partners.
- Options:
- M.1 Use all data (Regnerus baseline).
- M.2 Drop 29 misclassified cases.
- M.3 Drop misclassified + 6 borderline + 15 low-co-residence cases.
- M.4 Drop cases that never lived with parent’s same-sex partner.
Variable Construction: Family Type vs. Family Transitions
- Regnerus categorical types (IBF, single, step, divorced, adoptive, other, LGBT).
- Rosenfeld transition count:
- Broad: any adult entering/leaving household.
- Parent-only transitions.
- Hybrid model (Regnerus + transition count) also feasible (contrary to Rosenfeld collinearity worry).
- Philosophical split:
- Regnerus: instability is part of LGBT causal pathway → transitions a “bad control.”
- Rosenfeld: instability largely exogenous (legal discrimination) → must control for transitions.
Outcome Index Construction
- Rosenfeld (P.1): 19 variables; listwise deletion (17.5 % loss).
- Revised (P.2): 29 variables; allow ≤19 missing; only 0.77 % dropped; positive sign = better outcomes.
Weights & Outliers
- NFSS sampling weights correct demographic imbalance but inflate SEs.
- Winsorising long left tail of outcome index included as option.
Results of Full Multiverse
- Distribution centered closer to zero than control-only multiverse; modeling SE doubles (0.22).
- 95 % of estimates < Regnerus coefficient (Regnerus at 5th percentile).
- Sign pattern:
- 0.04 % positive (none significant).
- 76 % negative & significant.
- Robustness ratio total SE∣mean∣=3.14 (robust).
- Central substantive takeaway: negative effect persists but magnitude smaller than Regnerus original (≈ –0.48 SD on average vs. –0.87).
Influence Analysis (Table 11.3 Highlights)
- Largest shifts:
- Changing comparison group (C.1–C.6) alters coefficient by –44 % → +59 %.
- Dropping misclassified & borderline cases moves coefficient +16 % to –20 %.
- Weights double SEs; significance rate falls from 95 % (unweighted) to 58 % (weighted).
- Minor / negligible factors:
- Winsorising, race coding, quadratic age, outlier handling have ≤1 % effect.
Regnerus vs. Rosenfeld Multiverse Subsets
- Regnerus subset (no transition control):
- Mean β=−0.74; 99.9 % negative & significant.
- Rosenfeld subset (transition controls mandatory):
- Mean β=−0.35; only 64 % significant; heavily dependent on weighting.
- Weighted Rosenfeld models: 37 % significant (SE inflation).
- Choice of conceptual framework + weighting is decisive for “significance” narrative.
- Number of control combinations: 211=2,048.
- Total multiverse: 2,048×1,296≈2,654,208.
- Robustness ratio: RR=SEtotal∣βˉ∣.
- Family transition effect example (Table 11.1): each additional transition → β≈−0.07 on outcome index.
Ethical, Philosophical, Practical Implications
- Data quality concerns:
- Pre-screening on LGBT question may invite mischievous respondents.
- Small sub-population (1.7 %) magnifies misclassification error.
- Multiverse transparency exposes how plausible yet subjective decisions shape socially sensitive conclusions.
- Core lesson: publication debate should shift from binary significance to distribution of effect sizes under defensible assumptions.
- Policy stakes (adoption rights, marriage equality) warrant rigorous open science standards.
Connections to Broader Literature
- Echoes Jasso (1985) debate on handling implausible survey responses.
- Demonstrates general principle (Gelman & Stern 2006) that significance ≠ importance; sample size manipulations can mask effect-size stability.
- Administrative data studies (e.g., Mazrekaj, De Witte & Cabus 2020, Netherlands) provide contrasting positive findings, highlighting need for better measurement.
Exam Tips & Takeaways
- Memorise the two main multiverse dimensions: control choices vs. data-processing choices.
- Understand why family transitions may be a "bad control" (causal pathway) or an essential control (confounding).
- Be able to reproduce the logic behind Eq. 11.1 and simplified index model (Eq. 11.2):
Index<em>i=β</em>0+β<em>1LGBTparent</em>i+β<em>2OtherFamilyTypes</em>i+γ′Controls<em>i+ϵ</em>i - Know key numbers:
- 40 outcomes → 80 coefficients in original.
- 2,048 control models; ~2.65 M total models.
- Mean full-multiverse effect ≈ –0.48 SD; only 0.04 % positive.
- Distinguish between sampling SE vs. modeling SE; understand impact of weights on both.
- Recall that inclusion/exclusion of prank data, misclassified cases, and weighting determine magnitude and precision more than classic covariate debate.