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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What test should I use for a unipolar ordinal rating-scale?

I am trying to analyze answers to 5-point unipolar rating items. The possible answers can for instance be: Not at all difficult, Slightly difficult, Moderately difficult, Very difficult, or Extremely ...
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How does the Friedman test extend the sign test?

Every book/article claims this as if it's self-evident, but I have a hard time figuring out why. How do you get from the sum-of-squares style statistic of Friedman to the difference statistic involved ...
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I'm looking for a statistical test more robust than the sign test for my experimental analysis

I made an exploratory experiment that consists of a pair of readings. I used Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS) to read elements on several mineral surfaces, getting ...
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Using paired t-test or Sign test to compare two groups of correlated measures on the same subject?

I have conducted a survey where participants are shown 8 different advertisements: 4 of the ads attempt to evoke the feeling of guilt, 4 others attempt to evoke the feeling of shame. After seeing each ...
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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 ...
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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 ...
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Nonparametric Sign Test

Given Likert scale survey responses: ...
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What is the difference between a one sample t-test and sign test?

If I've conducted an experiment with only 10 samples and the data acquired have some wide gap in values, what would I use from the two statistical method. Here are my values sample values:
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How to test to test if one model is better than another on independent dataset?

I have two models that make predictions on the same independent data set. I would like to make a test and find out if one model is statistically significantly better than another. I've read that ...
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Kruskal wallis test for small dataset in R

I'm trying to test if there are systematic differences in a balanced data.frame composed by 25 observations of 3 variables: ...
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Paired sign test, when expected difference is not 50:50

I have a matrix of around 1000 species abundances from 40 sites e.g. ...
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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 ...
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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....
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Measuring magnitude of variation between 2 one-phase association exponential curves

I am currently testing the independence of two unpaired conditions A and B; with each condition representing a set of 12 values (aka bins) that compose a one-phase association exponential curve. Each ...
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What to do with a very big sample size? (effect size) [duplicate]

We have a peculiar problem, for which we have many questions, but cannot seem to find satisfactory answers (we did find a few ideas as to what to do, but we are not very certain they apply to our ...
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Rejection Region for Paired Sign Test

I'm taking an online stats course and I'm stuck on understanding a part of the textbook. It's in regards to the rejection region for the non-parametric sign test for a paired experiment. My book ...
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p-values in sign test

If we are given a list of $n$ independent measurments $\{0,0,1,0,1, \dots, 0,1,1,0,1\}$ of binomially distributed random variable $X$, we can use the sign test to check, whether the difference between ...
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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?
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Test statistics in IR (t-test vs Wilcoxon vs signed test) [duplicate]

I have just read this paper about different test statistics one could use in Information Retrieval (IR), discussing whether Wilcoxon, Sign-test or Student t-test would be more reliable for comparing ...
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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 ...
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Calculating Power of a sign test

I'm really stuck on part (e). I want to calculate the power of the sign test. So to find the power of first test. I let $M$ be the number of observations greater than $4.7$. Now I need to find Power ...
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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 ...
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Confused about the proper way of testing for an improvement or worsening

I want to check if a new equipment improves a score compared with the older equipment. My database contains the score with the old equipment, and the scores with each new equipment. I googled, userR'd,...
barerd's user avatar
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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^{...
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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 <...
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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 ...
Mozan Sykol's user avatar
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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 ...
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Why can we assume $\pi = 0.5$ in sign test?

When using the sign test, we assume, that: $\textrm{test statistic} \sim Bi(n_+ + n_-, 0.5)$ ie. that the probablity of $+$ or $-$ to occur is $0.5$. But how about the case of values being the same (...
mreq's user avatar
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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 ...
Andrea Valsecchi's user avatar
9 votes
1 answer
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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) ...
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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...
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