... the V forms of {1,1} pairs to be mis-perceived as σ´σ, and for the N forms of {2,2} pairsto be misperceived as ´σσ.3 Modeling preliminariesWe first describe assumptions and notation for models ... (N0). For 8See (Strogatz, 1994; Hirsch et al., 2004) for introduc-tions to dynamical systems in general, and (Niyogi, 2006) for the type of models considered here.1022N<N0, α is stable. For ... assume in Models 2–3 — aconstraint on the relative probability of σ´σ stress for N and V forms — has the drawback that thereis no way for the rest of the lexicon to affect apair’s N and V stress...