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.
699
questions
0
votes
0
answers
8
views
Adonis test significativo, but Adonis pairwise test dont?
I'm analyzing microbiome data un R, and for beta diversity i got aitchison distance, unifrac (weighted and unweighted) and Bray Curtis. Then i usted Adonis test (from vegan)
Note: i'm looking for ...
1
vote
1
answer
27
views
Paired or unpaired tests after using propensity score matching [closed]
I used propensity score matching in one of my studies to reduce the effects of confounding.
Although some authors have suggested that methods of inference appropriate for independent samples can be ...
2
votes
2
answers
60
views
How to test for normality on paired samples between two treatments when the number of observations per treatment is unequal?
I have mice which need to poke a device to receive food across a one hour period. The device records the number of pokes and poke_time which is the duration that the mouse remained in the poke hole. ...
- 23
0
votes
0
answers
11
views
Comparing a paired count data
I have a group of patients who are subjected to treatment A. I wish to compare the number of events/patient before and after the treatment. The duration of follow up of before and after therapy is ...
- 1
0
votes
0
answers
8
views
simulate the number of samples to be statistic relevant using a non-paremetric paired test
I have an experiment where a group of subjects must learn to associate some sounds to images (say, sound 1-image 1, sound2-image 2,... soundN-imageN).
They do a memory test (we present sounds and ...
0
votes
0
answers
9
views
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 ...
- 1
0
votes
0
answers
24
views
Hypothesis testing with data which is both pair and repeated-measures
Suppose I conduct an experiment to test the hypothesis that treatment A suppresses protein X. I am fortunate in that I work on kidneys, which come in pairs, however I am unfortunate in that I don't ...
0
votes
2
answers
67
views
Paired t-test for 2 patients?
For my doctoral thesis work, I conducted a small feasibility study on the use of a virtual reality therapy protocol in preventing aggressive recidivism in 2 treatment-resistant schizophrenic patients.
...
1
vote
0
answers
21
views
Sample size calculation for paired binary proportion - non-inferiority study?
I want to conduct a retrospective study, validating an algorithm. My data will be something like the following:
id
doctor
prediction
1
0
0
2
1
1
...
...
...
n
0
1
My study design is non-...
- 79
0
votes
1
answer
23
views
ANOVA is significant but also demonstrates non-inferiority
I have data that is looking at comparing a cheap (T) to expensive (V) ultrasound device with the hopes that the cheap is the same as expensive. There was 4 different examiners that used 4 different ...
2
votes
1
answer
23
views
Paired t test's statistic's numerator
I am a bit confused about the numerator of the t-statistic in a paired t-test. I know it's the mean of the differences between the samples, but is it the mean of the absolute differences or mean of ...
- 605
0
votes
2
answers
82
views
Wilcoxon and Paired t test results conflict
I have mean force data from patients gameplays, and I have to find if there is significant change in force from initial to final gameplays. I have applied paired t test and wilcoxon tests on the ...
user395461
1
vote
0
answers
59
views
Power analysis on paired proportions data
I'm interested in running a two-sided power analysis on paired proportions data and hope to use the stats:power.prop.test or pwr::pwr.2p.test function, but not sure if the functions assume paired or ...
- 1,051
0
votes
0
answers
37
views
What is an appropriate post hoc test after the Friedman test?
I've read several posts related to this, but I'm not sure.
so I'm posting the question in case it's redundant.
I have been conducting an experiment using a within-subject design, comparing three ...
- 101
1
vote
0
answers
20
views
Are paired matches in ranked data independent, if the original, unranked, continuous pairs are independent?
Let $(X, Y)$ be a randomly drawn sample of $n$ paired observations from a bivariate continuous population. It is clear that each pair is independent of the others, both pairwise and mutually. Let $R(X,...
- 336
1
vote
1
answer
67
views
Log-Rank Test After Optimal Pair Matching
I have clinical data and used optimal matching in the MatchIt package to match cases to controls on several variables. Matching was done in a 1:1 ratio, and balance was achieved.
I then did a Kaplan-...
- 225
0
votes
0
answers
31
views
Robustness of Mann Whitney U Test for partially paired data
I'm curious if anyone is aware of a publication that addresses the following matter or could provide a mathematically or reasonable response to the following question:
In a pre-post study where ...
1
vote
1
answer
105
views
Non-parametric test for comparing means of 2 or more dependent variables in R?
I have a matched paired dataset (student survey before a topic was taught and student survey after the same topic was taught) where I compare the means of their answers (answers are given in Likert ...
denise
1
vote
1
answer
33
views
What test can I use for comparing data grouped in pairs?
(Apologies for the less than descriptive title; edits welcome, also for the tags.)
I ran a survey which contained questions of the following type (the specific example here is fabricated; it is ...
user391554
0
votes
1
answer
24
views
Credible interval estimation for a difference of paired binomials
Assume one is given two series of binomially distributed data:
$$X_{1k} \sim Binom(n_{1k}, p_{1k})$$
$$X_{2k} \sim Binom(n_{2k}, p_{2k})$$
$$k\in \{1\ldots K\}$$
The goal is to estimate $p_2 - p_1$ ...
- 903
0
votes
2
answers
27
views
Paired t-test with redundant data
As part of my work I've gathered biological data for a set of (n=3) mice under two conditions ~ treatment and control. Since there is some inherent variability in behavioral research, I collected data ...
0
votes
0
answers
10
views
Testing the difference of the mean of the subgroups of the 2 groups
there are participants who are applied 2 different treatment methods. I tested whether these Treatment methods are effective or not with a paired sample t test, but what statistical analysis should I ...
0
votes
1
answer
134
views
Can I use the paired Wilcoxon test in R to compare two groups of different sizes?
I am trying to compare two groups of different sizes in a dependent sample. Here's a fictional example of how my data looks like:
...
- 11
0
votes
0
answers
18
views
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 ...
4
votes
1
answer
161
views
equal *population* variances in paired t test
I I want to perform a paired t-test to check if there's some effect, I have the distribution of "before" and the distribution of "after" the manipulation. Do I need to assume the ...
- 41
9
votes
1
answer
378
views
Why doesn't R output for a paired t-test match the formula for a confidence interval in the t-distribution?
My understanding is that the formula for a confidence interval when using a t-test is as follows:
$\bar x \pm t_{n-1,\alpha / 2} \frac{S_d}{\sqrt{n}}$
where $S_d$ is the standard deviation of the data....
- 183
1
vote
0
answers
6
views
Which test to use in a matched control study with unequal sample sizes?
I am performing a study in which I matched patients with treatment A 1:1 to patients with treatment B. Patients were then contacted for follow-up, since not all patients responded, the sample sizes ...
- 11
0
votes
0
answers
6
views
Finding missing SD using paired-test
I have a problem finding missing SD from a study
Please refer to the image below
Note:
What is provided?
Each timepoint's mean
p-value for paired-test between (post) and (pre) score
What is NOT ...
0
votes
0
answers
33
views
Half paired t-test?
I have data where all individuals have an observation at time 1, but then only half of the individuals have an observation at time 2, and I want to compare the means of times 2 and 1. Is a standard t-...
- 41
0
votes
0
answers
34
views
Assessing the Impact of a Specific Treatment on Survey Results: A Wilcoxon Signed-Rank Test Approach on Paired Samples
I have conducted a survey with several scale questions ranked 1-10 on a sample of n=18. I applied a specific treatment before and after the survey. However, I'm unsure about how to analyze the data ...
- 1
0
votes
2
answers
63
views
Seeking suggestions for a non-parametric version of two-way ANOVA/multi-variable MANOVA with repeated measures
I've been reading around this and keep coming up short so I'm hopeful there's an easy test for this.
I am measuring the differences (on a Likert scale) between matched (paired) pre- and post-lesson ...
- 1
1
vote
1
answer
54
views
Multivariate (5 dependent 1 independent variable) and paired data, multiple samples used. Which statistical test?
My data has 5 dependent variables (measured amount of oxygen, halides, nitrogen, sulfur, and organic) and one independent variable with 2 "treatments (flow rate, 1 Lpm or 2 Lpm). The catch is: I ...
- 11
0
votes
0
answers
20
views
Relationship odds for conditional data and odds ratio for unconditional data
I have matched paired nominal data, transmissions and non-transmissions of a risk allele M1 from parents with genotypes M1M2, M1M1, M2M2 to affected children. We can build a 2x2 contingency table and ...
- 43
3
votes
1
answer
56
views
Null Hypothesis in Paired t-test
Suppose that I was tasked to find if the mean difference between the current and starting salary of employees is greater than 15,000. How will my null and alternative hypotheses be?
Can it be:
Ho: ...
- 31
0
votes
0
answers
22
views
Paired Data collected; one condition is non-homogenous; Paired t-test possible?
I collected data on language attitudes to three languages in two moments of time, so the responders were the same. For two languages, the Bartlett test approved the homogeneity of variances, so then I ...
2
votes
0
answers
23
views
How to compare three sets of 'paired' categorical data
I am sorry I do not have the right terminology to ask as clearly as I would like.
I have three datasets of biomes. Each gives a biome by latitude and longitude (3 biome maps converted to tables). The ...
- 223
2
votes
1
answer
48
views
Mean difference (95% CI) between paired samples
I have some results from a study pre- and post-intervention. It's for an underpowered feasibility study, hence I am not performing formal hypothesis testing but I'd like to calculate mean difference (...
- 23
0
votes
0
answers
17
views
Paired t-test or two sample t-test with unequal variance?
I'm attempting to compare some economic forecast errors across institutions. I want to see if the mean absolute error is different from one institution to the other. Since the forecast errors apply to ...
0
votes
1
answer
53
views
Do bayesian paired t-tests assume normality?
I'm running a bayesian paired t-test using JASP. In the software, it says that one of the assumptions is that "The difference scores are normally distributed in the population". I'm a little ...
- 11
0
votes
1
answer
38
views
T-test for paired differences between sample means
Suppose I have pre-treatment samples and post-treatment samples for a group of patients. Let the treatment effect on each patient be the difference between the two sample means. Now I have a new ...
0
votes
0
answers
40
views
Can I combine two continuous variables to fit a linear mixed model?
Suppose a dataset as follows:
...
- 27
2
votes
0
answers
22
views
Is it possible to have interaction term in t test?
I have data of glucose measurements of 100 patients taken at 2 different time points. Of these, 40 people were taking pioglitazone drug and 60 of them were on placebo. I want to test (1) whether there ...
- 863
1
vote
2
answers
78
views
Regression Analysis for Proportional Data
I am going to try to simplify the context of my analysis into an apples/oranges scenario.
I have 30 baskets, each with 10 fruits. The 10 fruits are made up of a number of apples and oranges.
Each ...
- 13
0
votes
0
answers
11
views
Comparing two binomials with with partially matched sample
Imagine a scenario where I want to understand a population's support for a political candidate. I sample n=500 people randomly with replacement and ask them if they want to vote for candidate A or B. ...
- 159
0
votes
0
answers
16
views
Dual choice experiment - Is the paired sample Wilcoxon signed rank test the most appropriate?
I conducted an experiment with insects to find out whether one odour is preferred over another. The insects had the option of moving towards one of the odours (one of the stimulus zones) or staying in ...
- 46
0
votes
1
answer
31
views
Find most unique image from pair scores of a set of Images
Long story short, I have a set of vectors for each image after training on a model. I'd like to find the most unique image from the scores generated by ...
- 1
0
votes
0
answers
13
views
Friedman on one subject?
my goal is to define the interaction between 2 compounds. The data did not meet the assumptions of Two way Anova. I understand their is no alternative to testing the interaction. I am less interested ...
- 1
0
votes
0
answers
7
views
Non repeated paired observations along a continuous gradient - what to do?
Dear Cross Validators,
I have a data set of the following structure (don't mind the numbers):
subject_ID
Position_of_the_measure
Environment_condition
Variable_of_interest
1
A
10.3
40
1
B
10.3
36
...
- 1
2
votes
2
answers
43
views
Best analysis for site selection with paired data
I'm running into a problem after trying what I thought would be a simple analysis. I have 47 sites where I measured a variety of habitat characteristics (canopy cover, habitat type, percent of bare ...
1
vote
0
answers
38
views
I'm having trouble choosing between Wilcoxon matched pairs test and McNemar test for a data set
I have a data set on a large group of long-term stroke survivors. I need to determine whether there is a difference in ability (on a scale of 1-10) between their left and right arms. The ordinal data ...
