Learning edge momentum: a new account of outcomes in CS1

Not applicable — a theoretical account with simulation

CS1 students.

A theoretical paper proposing that tightly interlocking concepts create a positive-feedback loop in which early success makes later success easier and early failure compounds, producing bimodal outcomes without any innate-aptitude assumption. Located via citation index only; the body was not read, which is why it is recorded unresolved.

Robins' account is the field's best non-hereditarian explanation for why CS1 outcomes look bimodal. It now sits awkwardly, because Patitsas et al. (2016) showed that the bimodality it was invented to explain is largely an artefact of instructor perception — 5.8% of 778 grade distributions were multimodal. The explanandum failed before the explanans could be tested.

Not applicable — no estimates.

The theory was constructed to explain a phenomenon subsequently shown not to exist in 94% of the distributions where it was looked for.