Description:
In this article we study check character systems
that is error detecting codes, which arise by appending a check digit
an to every word a1a2...an−1 : a1a2...an−1 → a1a2...an−1an with
the check formula (...((a1 · ±a2) · ±2a3)...) · ±n−2an−1) · ±n−1an = c,
where Q(·) is a quasigroup or a loop, ± is a permutation of Q, c ∈ Q.
We consider detection sets for such errors as transpositions (ab →
ba), jump transpositions (acb → bca), twin errors (aa → bb) and
jump twin errors (aca → bcb) and an automorphism equivalence
(a weak equivalence) for a check character systems over the same
quasigroup (over the same loop). Such equivalent systems detect
the same percentage (rate) of the considered error types.