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In frequentist hypothesis testing, the $p$-value is the probability of a result as extreme (or more) than the observed result, under the assumption that the null hypothesis is true.

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Post-hoc corrections for multiple t-tests

I am comparing two groups (young vs. old adults) for differences in 5 brain regions (size) with independent t-tests. I also compare performance on three different aspects of a task with independent t-...
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Where does the t-distribution come from to calculate the p-value in linear regression?

I apologize in advance if I'm fundamentally misunderstanding something here. But I'm trying to figure out where the data is produced that forms the t-distribution on which one calculates the p-value ...
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p-value, literature request for the notion of p-value,statistical hypotheses testing [duplicate]

I would like to know the name of a statistics textbook in which the notion of $p$-value is treated as detailed as possible.An Amazon link will help.Thank you.
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34 views

How to compute p-value for Goodman and Kruskal's lambda and tau

How do I calculate p-values for Goodman and Kruskal's lambda and/or tau tests for association between categorical variables (measure improvement in predictability of the dependent variable given the ...
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4answers
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Does a uniform distribution of many p-values give statistical evidence that H0 is true?

A single statistical test can give evidence that the null hypothesis (H0) is false and therefore the alternative hypothesis (H1) is true. But it cannot be used to show that H0 is true because failure ...
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5 views

Correction for Multiple rmANOVAs followed by Post-Hoc tests

I'm researching the effect of one IV on four DVs which don'f form a structure. So I can't use a MANOVA approach. I'm using a repeated measures approach. Instead i would use four univariat ANOVAs. For ...
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0answers
42 views

Has the reproducibility crisis affected confidence intervals as well?

The reproducibility crisis has given many pause over the value (?) of $p$-values to measure the relevance of statistical findings. Given the interpretation of a $p$-value and some knowledge of ...
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21 views

Help in interpreting correlation coefficient and p-value

I have two variables called AC and Final_Coverage which I am trying to find their correlation. The range of ...
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1answer
17 views

Cox proportional hazards model and dummy variables

I have some doubts while doing this question. I tried out parts (a) - (c) and am quite confused by (d). Would appreciate if someone can help to check my work to see if I have done it correctly, ...
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33 views

Is multicolinearity testing altogether useless if the p-value on each regressor is less than 0.01?

Isn't the effect of multicolinearity to artificially increase the standard errors and thus artificially decrease the t-statistics, and thus artificially increase the p-values? If so, if all ...
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3answers
35 views

How to calculate the p-value of a test, that checked for a binary property?

16081 subjects were randomly assigned into two groups: test group: 7916 subjects control group: 8165 subjects Only the test group was exposed to something. During the test period 10 subjects of ...
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0answers
8 views

Permutation and multiple testing - permuting the test labels instead of sample labels?

I'm comparing $m$ p-values, where $m$ is very large. Every p-value comes from a two-sample $t$-test of two groups of size $n_1$ and $n_2$, where the $n_i$ are very small ($2$ or $3$). This leads to a $...
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1answer
24 views

Logistic regression (with dummy variables)

I have some problems with question (a) and (b) of this question. For question (a), would it be correct to simply look at the p-value alone? treatment B is coded as 0, it 'disappears' in the logit ...
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1answer
28 views

Normal distribution test ( D'Agostino and Pearson's) in Scipy - results don't make sense

I want to test if an array of numbers is approximately normally distributed. ...
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2answers
48 views

How to interpret the results of a chi square and p-values of a distribution uniformity test

I am reading about a method called consistent hash designed to distribute load among servers. The best case scenario would be a discrete uniform distribution where each server would get the same ...
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1answer
24 views

Block effect in mixed model

I have a problem i really can't wrap my head around. I have a dataset from a randomised block field trial conducted over two years. DV is Yield and IV's are Accession, SD and Year. The random effects ...
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0answers
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p-value from python OLS model, scipy stats.linregress() function and ind() function are different

I'm trying to see the p-value for an independent variable and a dependent variable. I fit a ols model and got the p-value as 0.001, then I used stats.linregress() function and got a p-value of 0....
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22 views

How can regression parameter SEs decrease when predictors are removed from the model?

What are some reasons that regression parameter $SE$s can decrease when predictors are removed from the model? Generally, adding predictors reduces the model's variance (MSE) which should shrink the $...
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1answer
57 views

Different p values for anova and summary in lme

I have done a repeated-measures study with two between variables: Groups (Control vs Experimental) and Religious affiliation (Yes vs No). The task was to rate 10 stimuli (images) on a 5-point Likert ...
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1answer
30 views

Getting one p-value for the whole variable in r?

I am running my glm and trying to get one p-value pr variable. Some of the variables ends up having 3 p-values. I would like to get out one variable for anesthesia and not 3 different according to the ...
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0answers
32 views

Using $H_0$ to calculate a $p$-value or critical value in a $t$-test

I seem to have trouble calculating (or rather, understanding) $p$-values or critical values when using a $t$-test or sometimes in a normal test. From what I know, the $p$-value is the probability of ...
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0answers
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What test should I use to test enrichment of domains in mutation set?

I have a list of mutations from a certain disease with affected proteins listed. Proteins have multiple domains, and I'm interested which domains are overrepresented. Example values: Humans have ...
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21 views

multiclass feature selection

I have multiclass(3 classes) dataset with 600 instances and 14 features which are texture feaures extracted from Gray Level Co-occurence matrix(glcm). I want to find out significant features among ...
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StandardScale variables have same scale but in different ranges and interpretation of Y-intercept

I am applying a Multiple linear regression, have several variables X1,X2,X3 to test their impact on Y and all of them have the same scale (quantity) but in different ranges of values. Should I ...
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0answers
5 views

Drop insignificant columns with categorical values in R [closed]

From what I have understood from this video: https://www.youtube.com/watch?v=qst0QGBntxc , if a field has a high P value, you should drop that column. But what if the fields in a columns have ...
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26 views

How should one compute the p-values of a two sided F test?

I have been studying this link. However, i can't really figure out how to calculate the p value for a 2 sided F test where the degrees of freedom are different and the F distribution is asymmetric. I ...
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1answer
23 views

Estimate confidence intervals for the P value of the Pearson's Chi-squared test [duplicate]

I have a contingency table where I estimate the p value Pearson's Chi-squared test, I want to take a confidence interval to validate this value P some code to do this by simulation monte carlo? ...
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0answers
65 views

How much better does one distribution approximate a value than a second distribution?

I have two samples (see graphic below), and I would like to know with what degree of certainty I can claim that one of them deviates less from the value 1.0 than the other. I am aware of this ...
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0answers
20 views

How to calculate prediction intervals for p values using just the obtained p value (Cumming, 2008)

I've been reading over Cumming (2008) on replication and p intervals. I don't appear to be able to replicate calculation of his p interval for p obtained = .05 following formula B3. I'd very much ...
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0answers
31 views

P-values: a misconception? [duplicate]

Statement: The lower the p-value corresponding to some test statistic, the greater the evidence against the null hypothesis. I see this statement everywhere, I would argue that this statement is ...
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1answer
33 views

Combining P-Values from multiple trials of the same experiment

this is my first question here, a little background about me, im a biomedical engineer, im studying a PhD in Neuroscience, and a Micromaster in Statistics and Data Science. Here in my lab, very few ...
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0answers
62 views

Asymmetric discrete distribution, how to efficiently calculate two sided p value from one sided p value

I want to test if a set of nodes have more or less links to another group than what it should be at random. Since I should not do any biased estimation of the direction of my test, I want to apply a ...
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3answers
184 views

Testing if two distributions have the same mean by using a sample distribution

ORIGINAL Phrasing: Let's say I have a population distribution, A. For example, this could be the distribution of the maximum height (not the current height) that someone will reach during their life. ...
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37 views

What is the point in reporting the z statistic of a z-test?

In my field some authors report the z statistic of a z-test in a generalised linear model and others do not. Does reporting the z statistic serve any purpose if the p value of a z-test or of a post-...
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43 views

Interpretation of P-value vs. Plot when performing Logistic Regression in R

I am new to R and Logistic Regression so I will try to be as clear as possible. I did the following really as a test case as proof of concept of what I've been trying to learn. I have performed ...
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1answer
44 views

How to minimize Chi-Square using the CDF instead of the PDF?

Suppose one has data that is suspected to obey a normal distribution. One computes a histogram of the data, and performs Pearson's Chi-Squared Test. To perform this test, one must compare the observed ...
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How can I test if a permutation hypothesis test produces valid results based on the probability distribution used?

I'm using the Join Count statistics to get insight if there is spatial autocorrelation in a categorical feature. I would like to test if the pseudo p-value returned comes from a valid hypothesis test ...
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Calculate if a point is significantly elevated above a group of data

I am using python if there is a nice way to achieve this computationally, but I am trying to calculate a p-value that a point is above a distribution like this: ...
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1answer
32 views

Bayesian p-value in wrong direction using step function in JAGS / BUGS

I have estimated a Weibull regression model in JAGS using rjags and R2JAGS. The estimated posterior predictive p-values using the step() function confuse me. They make sense (comparing them to lower ...
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1answer
82 views

logistic regression vs. linear regression

in the following table (association between cognitive score and Folate intake), the beta coefficient represents difference in slope between different groups with the standard group. the interpretation ...
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2answers
125 views

Significance vs. goodness-of-fit in regression

Assume that I am interested in analyzing the following linear regression model: $$ Y = \beta_0 +\beta_1 x_1 +\beta_2 x_2+e $$ Please explain the difference between testing the p-value for each ...
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1answer
48 views

Is LMM (lme4) the right way to go? [closed]

I do realize that there are already some questions about the p-values in lme4 and the nested effects but I've got a somehow specific case and failed to find anything that applies to this. I have ...
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42 views

A question about ``frequency of p-values''

In NIST 800-22, a battery of tests for rejecting a random number generator, they present their results with 10 columns expressing the frequency of p-values (section 5.7, interpretation of results, ...
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1answer
36 views

Can I perform a Chi Square test comparing the one year mortality of my 160 patients versus the 108000 patients of a cohort in the litterature?

I have exactly zero experience with statistics. I was interested in comparing 1 year mortality of patients $\ge$ 60 years old versus $<$ 60 in a cohort after a specific intervention. I performed ...
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1answer
30 views

Problem in accuracy when calculating p value from a 95% confidence interval

For my meta-analysis I have to obtain univariate analyses (HR, 95% CI, p value) from different studies. I came across one study with a given HR: 1.19 and 95% CI: 0.46 - 2.51. By surfing on the ...
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2answers
51 views

Does the effect size mean the expected difference between the means

I am designing an experiment and want to define the sample size. To identify this, I am setting my significance level to 0.05 and the power to 0.8. My alternative hypotheses says the two means should ...
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2answers
51 views

How to work out p-value if variances of two groups are different?

How do I work out the p value if the variance of my control and experimental group are different? I can't do the t-test anymore. How do I work the p -value out, what method? Also, my two groups are ...
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1answer
36 views

Bootstrap Confidence Interval, f-value and p-Value

I am trying to understand the intricacies of Linear Regression (1 predictor, 1 response). I am using Istanbul Stock Exchange dataset (https://www.kaggle.com/uciml/istanbul-stock-exchange) to do the ...
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P values all equal to 1 after using bonferroni or hommel

Several topics are talking about this but in my case my p values are generated differently. My p values will be calculated simulating $N$ (in this case 5000) random gene groups of size $g$ of the ...