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 ?
For example, if we know the 15 members that comprise the part of the Politburo not in the PSC, but we do not know how they rank in relation to each other, we assign them a tied rank that places them below the PSC and above the rest of the CC.
This means that we must generalize metrics on SN to deal with the case of tied ranks; this will also suffice to handle the situation in which two top elite lists do not include the same members--we take them to provide only partial information, with unlisted people assumed to be ranked equally, but below listed ones.
Tied ranks are replaced by averaged ranks (Table 4).
The double sum in Equation (1) is extended over all sets of t tied ranks in each of the n rows.
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.
Then, the efficiencies of the 3 dominance indices, CBI, DS and FDI in given unique ranks (absence of tied ranks) were compared to determine the best dominance index for each of these societies.
Although two skills--the measuring of vital signs and performing a breast exam--were found to have a significant increase in confidence, there were more tied ranks than either negative or positive ranks for these two variables.
The researchers hypothesize that the number of tied ranks in the variables of vital signs measurement and breast exam may be related to experiences in a prior assessment course.
Because of the limited space generally allocated to letters to the editor, we have compared the rankings for each of the two ranking methods for the 20 (actually 21 because of tied ranks) most frequently published faculties in our sample of 61 doctoral faculties.
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] 0.05) or rejected (P [greater than] 0.05), between crabs familiarized with Mytilus and crabs familiarized with Geukensia (Table I).