Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [sign-test]

Non-parametric test to compare two paired samples. Not to be confused with the [wilcoxon-signed-rank] test.

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In what situation would Wilcoxon's Signed-Rank Test be preferable to either t-Test or Sign Test?

After some discussion (below), I now have a clearer picture of a focused question, so here is a revised question, though some of the comments might now seem unconnected with the original question. It seems that t-tests converge quickly for symmetric…
justme
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How to choose between sign test and Wilcoxon signed-rank test?

I am trying to pick one from these two tests to analyze paired data. Does anyone know any rules of thumb about which one to pick in general?
Sheldon
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Alternative to the Wilcoxon test when the distribution isn't continuous?

One of the assumptions for using the Wilcoxon sign-rank test is that the underlying distribution is continuous (see here.) However, there are cases (for example, when analyzing Likert scale data) where this assumption might not necessarily hold. In…
Tal Galili
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Is there an unpaired version of the sign test?

I wasn't able to find one on Google, and was wondering if one exists...
Tal Galili
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Can McNemar's test be improved upon by adjustments for zeros like those in a sign test?

McNemar's test is a special example of the binomial sign test, but the ('vanilla') sign test suffers from bias due to ignoring differences equal to zero. McNemar's test statistic is given by: $\chi^{2} = \frac{\left(|r-s|-1\right)^{2}}{r+s}$, where…
Alexis
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Is the binomial sign test really the exact McNemar test?

I am calculating two different $p$ values for the McNemar test and what I believe is the corresponding exact test, even for combined counts larger than 25. Take, for example the contingency table Posttest Pretest Outcome A …
BMS
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Sign test for matched pairs that are non-integer

I have paired data as follows. These are proportion correct scores (ranging from 0 to 1) from multiple experiments in which Treatment X and Treatment Y were administered. Treatment X: 0.25, 0.35, 0.15, 0.15, etc. Treatment Y: 0.55, 0.56, 0.33,…
Altair555
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Find test statistic for sign test

I'm investigating if people are walking more than they bicycle. I have $n = 55$. $30$ of them are walking more and $25$ are bicycling more. I need to 1) find the test statistic for the sign test of $H_0: p=0.5$ against $H_a: p \neq 0.5$. 2) find…
Hopkins
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Is the sign test appropriate to test whether values in one distribution are generally lower than the other?

Generally, the sign test is used to test the hypothesis that the difference median is zero between two continuous distributions (Sign test). I am trying to understand whether it can be adapted to prove that the values from one distribution are…
Mozan Sykol
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Treatment of Ties in sign test (paired-samples sign test)

I'm curious about the validity of removing/ignoring ties when calculating the p-value for the sign test. By ties I mean ($x_{before} = x_{after}$, where $x$ represents the measurement). According to wikipedia's example, this procedure is…
idnavid
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Which test to perform when checking for predicted vs actual sign of a relation between two variables?

I have been contemplating which test or statistic method to implement, in order to check that the variables I use throughout my analysis, actually have the predicted relationsship with the dependent variable. Now, to preface this, I do not actually…
Philip
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Nonparametric Sign Test

Given Likert scale survey responses: "Very Satisfied", "Very Dissatisfied", "Dissatisfied", "Neutral", "Neutral", "Very Satisfied", "Satisfied", "Very Satisfied", "Very Satisfied", "Satisfied", "Very Satisfied" Map between Likert scale and numeric…
inkalchemist1994
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What software implements the multiple comparison sign test?

What software implements the multiple comparison sign test as described in Steel (1959)? References Steel, R.G.D. (1959). A multiple comparison sign test: treatments versus control. Journal of the American Statistical Association, , 767-775. PDF
Andrea Valsecchi
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scale of measurements in sign test and signed rank test

Can some one help me to understand the right scale of measurement to use in sign test as well as in signed rank test? I read a certain book it says nominal scale is used in sign test while ordinal scale is used in the signed rank test, the other…
Trecy Johnson M
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When Should The Following Tests Be Run

What are the assumptions behind each of the following types of tests (i.e. what are the prerequisites to running each test). Paired-t Sign Two-Sample t Pooled Two-Sample t Two Proportions F I really am getting confused seeing what would warrant…
Julian
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