Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [paired-data]

Paired data arise when an experimental or observational study design deliberately samples two units as a dyad to form a basis of comparison. Use this tag for any question about paired data or their analysis.

Paired data arise when an experimental or observational study design deliberately samples two units as a dyad to form a basis of comparison. Typically these units are highly correlated and thus warrant the use of statistical methods for correlated data. Examples of paired designs include twin studies, case-control studies with 1:1 matching of cases to controls, split-plot experiments, and pre-post tests. Examples of conditional likelihood based statistics include a paired t-test, conditional logistic regression, and McNemar's test.

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Calculate paired t test from means and standard deviations

I feel a bit stupid, but I seem unable to find a way to calculate a paired sample t-test having the group means and standard deviations (not the individual data) of one group before and after an intervention: mean_pre: 11.7, SD_pre: 2.4 mean_post:…
Claudio
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Test for study design few subjects many paired observations per subject

I'm having difficulties in contructing a proper statistical approach to analyzing the data described below. We have 3 subjects which we each measured on 20 different days. On each day we measured a certain variable Y in two conditions: A and B.…
Nynke
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Should I raise alpha level to increase statistical power for my data?

I am running a paired samples t-test. n=29. Should I raise the alpha from .05 to .1? I was told this can increase statistical power for this sample size but should it be done? Currently my paired sample t-test says, t(28) = 1.593, p = .061,…
midori
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Use paired t-test to compare mean scores of 2 interventions, if 1 group got only 1 and another got both?

Let's say there was an intervention delivered using method A and method B. There was a post test asking participants about satisfaction on a Likert scale immediately after each method was delivered. We want to know which was better (i.e. higher mean…
xdrenched
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Survey Response for a Paired Data

I have a set of 15 perception questions asked before and after a course to the same group of 13 students. The responses are 0%, 20%, 40%, 60%, 80% and 100%. What is the best way to analyze them to test for significant difference?
Bani
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paired comparisons within subgroups or across all subgroups

We are counting the numbers of cells (oligodendrocytes) that develop in mutant mice versus littermate controls, and wish to know if the numbers are different. Typically we can get 2 mutants and 2 controls in each litter (of ~8 pups; mutants are…
Billr
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How to compare wild type and mutant group (n=3) across distance - which statistical test?

I am comparing the p-Erk intensity of wild type (n=3) and mutant (n=3) group around the PSPB region in the developing mouse brain. I have collected intensity data throughout a line drawn across the area of interest, I have made the X axis into 12…
JoanneK
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Help deciding test for numerous (not pairwise) paired comparisons with small sample size

I am completing a study that gathers subjective, quantitative data on a 0-10 Likert scale from patients that have single-sided deafness, that is normal hearing in one ear and impaired hearing with a cochlear implant in the other. They are asked to…
smkyyy
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Need help with figuring out variables for t-test for dependen samples

I am trying to figure out t test for dependent samples and need help. Let's say that our research question is "is there a difference between length of essay and narration text in children with developmental language disorder", in class we learned…
Lucija Crvenic
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How can I determine the significance of two sets of paired, independent measurements?

Let's assume I am trying to find out whether individual people are better at beer pong while sober or drunk. In this experiment I do four trials. On Monday, I first have them throw 100 times sober and record their results. Then, I have them drinks x…
spleen
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n= 29, p value for three tests: .061, .09 and .13 but all trending in predicted direction: How to report?

So I ran three paired samples t-tests to see if people did a certain action more after hearing a target stimulus. my prediction is that they would do the action more. All tests were one-tailed as i was only looking at one direction: did it increase…
midori
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Quantify the similarity between two sets of data

I have two sets of data y(x), one from experiments, and one from simulations. The datasets are naturally paired, as the same 80 different test set-ups were used for both data sets. I would like to quantify the difference between the data sets with a…
Toivo Säwén
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Difference in the levels of two drugs over time

I have repeated measures (at different time points) of drug levels (different variants of the same drug) within two different subjects. After the first round of measurements the drugs were reversed and administered to the same two subjects. Thus,…
Edward
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Power of the test

How can I calculate the power of paired t-test if the null hypothesis mean is equal to 0. With a standard deviation 0.0373, sample size n=12 and alpha 0.05.?
Aina M. Rashid
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Is a paired t-test appropriate for this data?

I have 3 sites, that have been measured annually for abundance of species A and abundance of species B. Do I use a paired t-test to see if species A is having an impact on species B abundance?
Patrick
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