No evidence that age affects different bilingual learner groups differently: Rebuttal to van der Slik, Schepens, Bongaerts, and van Hout (2021)
Hartshorne JK · 2024
grade Dcritiquedeveloper-lednot-applicable
Sample
reanalysis of the same dataset
Population
As Hartshorne et al. 2018
Design
A rebuttal by the author of the paper under attack, published in Language Development Research. Recorded as developer-led because the defendant is the original author; it is argument about analysis, not new evidence.
Key findings
Argues that van der Slik et al.'s tests do not distinguish a sharp decline from a gradual one - they test whether decline is ASYMMETRIC, slowing with time - and that once corrected, every type of bilingual examined shows a sharp drop in learning rate in late adolescence. No concessions are made.
Genetic confound
Not applicable - no new data.
Replication notes
This is the second turn of a two-turn dispute. Neither side has produced new data; both are modelling arguments over the same self-selected internet sample. That is the reason this topic does not treat the breakpoint as established.
Effects
| Outcome | Metric | Value | Measure | Timing | Vs | Horizon | Class |
|---|---|---|---|---|---|---|---|
| Whether a late-adolescent drop in learning rate holds across learner types | reanalysis conclusion | sharp drop reported for every bilingual type examined; original conclusions defended in full | researcher-designed | cross-sectional reanalysis | none | not-applicable | domain-skill |
Cited by
- Is there a critical period for learning a second language, and when should a child start?mixedconf: mediumgc: medium