tied rank

tied rank

[′tīd ′raŋk]
(statistics)
If two distinct observations have the same value, thus being given the same rank, they are said to be tied; this presents difficulties in the Wilcoxon two-sample test, the sign test, and the Fisher-Irwin test.
References in periodicals archive ?
A common problem during the construction of dominance hierarchies is the occurrence of tied ranks that prevent the total ordering of individuals, and consequently, prevent the correlation of dominance hierarchy with other biological variables.
Mussel selection data from the foraging test was analyzed using a Wilcoxon signed rank test, a Mann-Whitney test with tied ranks, and a chi-square 2 X 2 contingency table (Zar, 1984).
A Mann-Whitney test with tied ranks determined that there was no significant difference in total mussels, regardless of species, eaten (P [greater than] 0.