Animation 1: Boundedness and Ordinal Resolution Bias

Non-uniform cutpoint spacing and bounded scales together shape the observed mean–inequality relationship

The ordinal resolution effect. Ordinal probit estimates of life satisfaction typically show probit-spaced cutpoints: thresholds are denser near the centre of the scale and sparser near the extremes. This means responses near 5 distinguish finer differences in latent wellbeing than responses near 0 or 10. Consequence: for the same true latent σ, distributions centred near 5 are better-resolved and produce a higher observed SD than those near the endpoints — producing an inverted-U in SD, opposite in sign to the pure ceiling/floor effect.

Use all three sliders. Slider 1: latent mean (μlat). Slider 2: latent SD (σlat) — controls how strongly the bounded scale truncates the distribution. Slider 3: cutpoint compression α (0 = uniform, 1 = strong centre compression — middle categories narrow, edge categories wide; the three central gaps are held equal so response 5 isn't artificially squeezed). The dashed reference curves (recomputed at the current σlat) show the two α extremes; the solid curve is the current blend.
Latent mean (μlat): position on latent wellbeing axis 0.00
Latent SD (σlat): spread of latent wellbeing 3.00
Cutpoint compression (α): 0 = uniform → 1 = strong centre compression (narrow centre cats, wide edge cats) 0.00
μlat0.00
σlat3.00
α0.00
Obs. mean
Obs. SD
Gini
P80–P20
α=0 (uniform) — dashed
α=1 (compressed centre) — dashed
α = current slider value — solid
current (μlat, σlat)