Questions tagged [hypothesis-testing]
Hypothesis testing assesses whether data are inconsistent with a given hypothesis (usually a null hypothesis of no effect).
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Why does the p-value increase when I add more observations to my t-test?
I am comparing the means of two groups using an independent two-sample t-test in R. Initially, I had the following samples:
Group A: n = 15, mean = 52.3, sd = 4.8
Group B: n = 15, mean = 48.1, sd = 5....
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How to test if there's a statistically significant difference between two counts, based on relative percentile?
How to test if there's a statistically significant difference between two counts?
I'm struggling to test if two ratios on the same row of my dataset are significantly different from each other. I need ...
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Assumptions when conducting hypothesis test for population mean
Consider the following problem:
A report in USA Today stated that the average age of commercial jets in the U.S. is 14 years. The population of commercial jet age is known to be normally distributed ...
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Test of independence with three levels on 6 observations on a 1-7 Likert rating
I've data from an in between subject study asking participants to rate features in respect to 3 objects, let's say a plant, a stone and a bottle. Each participant gets shown one object and ...
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How do I plot the power of the likelihood ratio test [closed]
I have a random sample of $25$ observations, which follow a normal distribution with mean $\mu$ and variance $100$. I have to graph the power of the likelihood ratio test of $H_0: \mu =0 $ and $H_A:\...
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Endogenous Sample Selection and Heckit Correction in relation to Research Question
I am researching the funding amounts of start-ups. I am calculating two models:
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Testing that a multivariate mean approximately equals a vector of constants
Suppose we have a $p$-variate random vector that has a multivariate Normal distribution, $\boldsymbol{X}\sim MVN(\boldsymbol{\mu},\Sigma)$. My hypothesis is that the mean vector contains only zeros, $\...
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Eliminating latent variables in structural model using PLS-SEM
I have a very simple structural model, with 11 exogenous constructs predicting 1 endogenous latent variable. I examined my structural model with PLS, and I got very poor results - none of the 11 paths ...
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Comparing median scores in two groups and estimating/quantifying the difference
I have two groups (A and B) and data on 3 different biomarkers (a, b and c). What I need to investigate if there is any difference between the groups in each biomarker, and if the difference between ...
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Anova and ChiSquare with 4 groups
I have asked some participants (29) to complete several tasks, and I have the results for the people that successfully completed it, and those who didn't.
I have a breakdown by age (4 groups) and I am ...
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General guidelines on how to derive a hypothesis statistical test?
In general, the process of hypothesis testing can be divided in 4 steps:
Formulate the practical problem in terms of hypotheses.
Calculate a statistic $T$, a function purely of the data. All good test ...
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Why can I fit a horizontal line through the 95% confidence intervals region of my OLS model even though its overall p-value is close to 0.05?
Original question: ~~I don't know how to intrepet the result I got from my OLS analysis. The issue is that I can fit a horizontal line within the 95% CI even though the overall p-value for the model ...
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Can Kruskal-Wallis be used for discrete data?
I have a data frame with variables that are counts, nominal (two groups) and continuous. Two of the continuous variable follow a normal distribution; the counts variables do not follow a normal ...
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Guarantees of different experiments with the same p-value
Frequentists often explain that:
If we construct a 95% confidence interval for the mean of some unknown distribution using n random samples from a population, the ...
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Significant results from ANOVA post-hoc Tukey's, insignificant with welch-ANOVA post-hoc Dunnett's T3
I performed one-way ANOVA tests with post-hoc Tukey's to look at multiple comparisons and got highly significant results, but noticed the $F$-value on the ANOVA was high. The SDs in the groups were ...
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Do you reject the null hypothesis when $p < \alpha$ or $p \leq \alpha$?
This is clearly just a matter of definition or convention, and of almost no practical importance. If $\alpha$ is set to its traditional value of 0.05, is a $p$ value of 0.0500000000000... considered ...
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Subsampling large dataset before testing?
I'm running a Kruskal test with Conover post-hoc test to assess if there is a statistically significant difference between a numerical and a categorical variable with R.
I previously created boxplots ...
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Understanding Fisher’s combined probability test in my analysis
I'm trying to understand Fisher's combined probability test, especially how I used it in my analysis. I have 25 datasets, each one containing genomic data from cancer patients. I conducted a ...
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Statistical test to show the importance of one cluster
I have one dataset of two variables (x,y). When the data is plotted in a 2D diagram, I see some data points create a good cluster, while the other data points are scattered randomly.
Here is an ...
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Test for significant differences for data between 0 and 1
I have to test for significant differences between scenarios. Data consist of the length of a segment divided by the total length of the network. They are distributed between 0 (never equal to 0) and ...
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Using a test of independent data on paired data; valid or not?
My specific question is about using a Mann-Whitney U test (MWUt) (meant for 2 independent samples) on data which is actually paired (correlation between the 2 samples).
I have searched this site, and ...
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Two ideas to include measurment errors in a Binomial Test with different results
I have a measurement with two possible outcomes, let's say 0 and 1. If the outcome of the measurement is 1, the true value is always 1. If the outcome of the measurement is 0, there is a chance of 1% ...
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Testing for difference in means between two groups for which each measurement has a unique associated uncertainty
I am wondering what type of statistical test would be appropriate to test for a difference in means between two groups for which each measurement has a different uncertainty. For example, I want to ...
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Handling multiple comparison corrections in association rule mining
We’re working on a project applying association rule mining to environmental DNA (eDNA) datasets, and run into some uncertainty regarding how to best handle multiple comparison corrections in this ...
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Asymptotic consistency of hypothesis tests
We’d like for our hypothesis tests to be statistically consistent, meaning that as my sample size grows infinitely large, I will arrive at the right answer. But from my understanding, usually the ...
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