Table 8.5 shows the same data, with the order of the observations reversed in the second and fourth strata. This has the effect of making tᵨ negative, because it makes the majority of the cross products between deviation from the strata means negative for pairs of observations that lie in the same systematic sample. In the first systematic sample, for instance, the deviations from the strata means are now -4.1, +4.8, -5.3, +4.9. Of the six products of pairs of deviations, four are negative. Roughly the same situation applies in every systematic sample.