Seven Differences and Their Ranks
Seven paired differences (after minus before) are: $-0.3,\ 0.8,\ -1.1,\ 1.4,\ 2.0,\ 2.6,\ 3.5$. Apply the exact Wilcoxon signed-rank test of $H_0$: the differences are symmetric about 0, against the one-sided alternative that they tend to be positive. The statistic is $T^+$, the sum of the ranks (by absolute value, smallest rank 1) of the positive differences. Under $H_0$ each of the $2^7$ sign patterns is equally likely. Give the exact one-sided p-value as a reduced fraction.
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Source: Wilcoxon signed-rank test (F. Wilcoxon, 1945). Data written for AxiomIQ. Statement written for AxiomIQ.