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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Test statistic for binomial distribution

I know that a test statistic is used to help us in hypothesis testing, etc. We compute the test statistic, and then compare it to the $\alpha$ value to reject or accept the null hypothesis. For a ...
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Calculating p-values for two tail test for population variance

A sporting goods manufacturer claims that the variance of string tensions for any decent tennis racquet should be about 9 pounds. The string tensions of 18 randomly selected tennis racquets produced a ...
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Why do we use the chi-squared test to test independence of 2 categorical variables?

I sometimes use the chi-squared test to test the independence of categorical variables. I know how to do the test but don't know the underlying concepts and details. So, I was wondering about the ...
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16 views

White's Reality Check Hypothesis Testing question

I am running a hypothesis test based on White's reality check p-value. I am getting a weird result for my univariate time series of returns. In essence, I am following a code on MATlab to run the test ...
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12 views

How do I test the significance of my correlation coefficients for various NONLINEAR regressions?

I have a set of 25 points and I used a TI-84 calculator to calculate the linear, quadratic, logistic, exponential, and power regression models for this data set. I have, likewise, obtained the r^2 ...
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28 views

Repeated measures, random effects structure, confidence intervals and p-values don't fit

I have repeated measures data of plant species richness with the following variables: richness (response variable measured each ...
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24 views

Confidence intervals and p-values of multiple factor analysis lead to different conclusions?

I have the following model: man94_141 <- glmer(richness ~ year*block + (1|tr) , family=poisson , data=datasan94_14) where richness is the number of species ...
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24 views

$p$-value for non-standard asymptotics

Suppose I have an asymptotic result like $$\sqrt{n}(T_n - \theta) \overset{D}{\to} \sum_{i=1}^k \lambda_i X_i$$ where $X_i$ are independent $\chi^2_1$. i.e. some test statistics $T_n$ is ...
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20 views

Multiple comparison FDR for positively correlated p-values and test statistics

I have the following scenario: I have sampled two subjects on three days. I am looking for a consistent and statistically significant difference between two collections of measurements (call them A ...
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5 views

Doubts regards the contrast between two samples to analyze their expected values

I have this two samples: pob1<-rchisq(90,12) pob2<-rchisq(50,7) For making a contrast to see whether if I can guess that their expected values are equal or ...
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119 views

Why is high positive kurtosis problematic for hypothesis tests?

I've heard (sorry cannot provide a link to a text, something I have been told) that a high positive kurtosis of residuals can be problematic for accurate hypothesis tests and confidence intervals (and ...
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20 views

Is there any way to convert from a posterior probability to p-value, or the opposite?

I have results of a study from associations of a variant with a phenotype in the form of posterior probabilities but I was wondering if there is any way to convert these to p-values, even making ...
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12 views

how to know if the observed overlaps in independent sets is significant?

I have a list of names ( derived from a statistical test ) that overlaps with a list of names ( set2 ). I generated a random list of names ( random ) and overlapped with set2. How do I know if the ...
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31 views

p-values of the coefficients or AIC for model selection in multiple regression

I´ve got two models from a multiple linear regression (A and B, see below) and don´t know which to select. I want to predict a value called AW as good as possible, so I´d like to have the highest r². ...
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15 views

Testing for normality - low p-value

I've a dataset with about 12k values given. It looks like this: When I try to test for normality I get following results, where p-value is extremely slow: ...
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11 views

Interpreting output from lsmeans tukey test

I'm running post-hoc analyses on linear mixed models I ran for a dataset. I'm not totally sure how to interpret the output from lsmeans which is as follows: ...
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31 views

p-value in interpreting path coefficients in path modeling of PLS-SEM

I'm beginner at statistics, so my question may seem to have non sense for some. I was trying to interpret a PLS-SEM results, which is a kind of path modeling. The results of path coefficients are ...
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20 views

Smaller p-values on a selective multiple regression analysis [duplicate]

When I run a multiple regression analysis in Excel on 20 independent variables and 1 dependent variable (in two goes), I obtain in the summary a set of p-values. When I select the (six) ones that are ...
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22 views

P values and calculating residuals in chi-squared contingency tables

Given an n x m contingency table I calculate a chi-squared value and probability for that table telling me if there are cells that differ significantly from the mean. I go to calculate the adjusted ...
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19 views

p-value of observation in non-parametric distribution

The question is really naive but i'm stucked in... I'll eliminate all the biological details and experiments and quote just the problem at hand. I would like to know how to proceed. If the data (or ...
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22 views

Multiple hypothesis testing in SEM

When doing regressions, if we are testing multiple hypotheses, there are traditional ways to deal with it (e.g. Bonferroni correction etc.) And if we are also doing variable selection, there are ...
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36 views

Can I run a normality test on percentages?

First I'll start out with some background information. I conducted image analysis on 200 images to identify the area % of 7 different phases. I then averaged the results from each of for the 200 ...
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27 views

How to interpret P-value from mixed model and P-value from overall ANOVA?

I fitted mixed effect model with several effects with lme package in R by command ...
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23 views

one-sided survival log rank test p-value

I want to compare two treatments for an oncology indication. I used a log rank test as two treatments (variable treatment) with time (variable month) and censor status (variable censor). Below is the ...
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37 views

Confidence Interval and P Value uncertainty for Permutation Test

I'm very new to resampling techniques. As I'm learning randomization tests right now online, there are two main questions coming to my mind: YES, it's easy and intuitive how p-value is computed with ...
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How to calculate p-value for NPS (Net Promoter Score) result?

There's already an excellent answer on calculating MoEs and confidence interval to compare NPS results from two samples. However I would like to find a p-value (or at least a z-score) as a result of ...
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109 views

Confusion regarding p-values and false discovery rate

I get stuck with understanding of the following two statements (from Wikipedia on p-values): The p-value is the probability of obtaining at least as extreme results given that the null hypothesis ...
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21 views

How to test significance in different betas?

My data set consists of individual real estate listing prices (rental and selling) that vary along time. I want to know how time on market (TOM) affects the price so I'm regressing every single house ...
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22 views

Significance tests for streaming data

I want to compare multiple classifiers on multiple data streams. For a stream of length $n$ I test a single classifier each $t/c$ time steps using a dedicated (hold-out) subset of my data and ...
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27 views

Calculating a single p-value from a posterior sample generated from MCMC

I'm using permutation tests or Monte Carlo simulations in order to attach p-values to a test statistic by randomly shuffling sample labels. The data I am using is a tree that I have estimated using ...
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25 views

How to interpret SPSS p-value for one tailed tests

Suppose H0 = Mean 1 - Mean 2 > or = 0 and HA = Mean 1 - Mean 2 < 0. We do an unpaired t-test in SPSS to get our p-value. The SPSS p-value is 0,534. This P-value is two tailed, so we have to devide ...
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3answers
57 views

What lowers the p-value besides the sample size?

The title pretty much says it. Sorry, it's so unspecific, I am not asking the question for myself and I am not familiar with stats.
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32 views

Interpretation of statistical outcomes: studies of “Moral Hypocrisy”

I am dealing with the studies of C.Daniel Batson, who provided several studies and experiments to reveal moral hypocrisy. I think that I understand the basic idea of his theory, however I am not ...
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Can I use p-value as the criteria to generate ROC cuvers

I developed an algorithm to predict positive and negative samples. The algorithm returns a p-value for each sample. Can I use the p-value (ranging from 0 to 1) as the criteria to generate a ROC curve? ...
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14 views

Relationship between pval and sample size with >2 categories

I know that in general an increase in sample size results in a decrease in the p-value, sample mean being held constant. However, say that i have one categorical predictor variable with three values, ...
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1answer
26 views

p-values in a Cox-Regression model

I have a question regarding the output of a Cox-Model I obtained by stepwise model selection. My model includes now some variables with a p-value below 0.05 and some above 0.05. Since I want to ...
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2answers
53 views

meta-analysis of p values

I am a bit confused about doing the meta analysis with my data. Given z-scores I calculate p values in a way: p.values = 2*pnorm(-abs(z)). Then I would like to ...
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48 views

If A/B test results are not significant, how does increasing sample size affect things?

If I run an A/B with the recommended sample size (using this for example), and at the end my results are not significant, what can be done at this point? If someone requests to continue running the ...
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1answer
27 views

P-values vs Coefficient Values in GLM

In the following excerpt, the author noted an association with the dependent variable based solely on the p-value and not the magnitude of the coefficient. Here is a link to the study. I thought ...
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38 views

Calculate p-value for difference between ICC values

I cannot seem to find an answer to the following problem: I am doing interreader correlation studies where I calculate ICC values. It is quite easy to do this in R, but how do I calculate a p-value to ...
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1answer
46 views

P-Value for logistic regression model in R [closed]

If I create a linear model in R, I get a p-value for the whole model. When I create a logistic regression model, I don't. Why is this? Linear Regression ...
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29 views

Calculating p-values from discrete distribution

We have a couple sets of gene expression data (from microarrays) which we are examining to try and determine which sets of genes are significantly and similarly differentially expressed between two ...
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1answer
28 views

Selecting model in GLM logistic with AICc, p-values for best AICc are all insignificant?

I have one potentially causal predictor and a number of covariates that I tested via AICc model selection in logistic GLM. I found that alone, the causal predictor has a low AICc (~19) and a ...
0
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1answer
57 views

Interpretation of ADF(Augmented Dickey-Fuller) and KPSS(Kwiatkowski–Phillips–Schmidt–Shin) tests for time series [duplicate]

Can anyone please clarify for me the differences between ADF(Augmented Dickey-Fuller) and KPSS (Kwiatkowski–Phillips–Schmidt–Shin) tests in testing the stationarity of a time series? I tested my time ...
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15 views

Correct Sample Space for Calculating P-Value

Suppose there are two variables, x and y, and we wish to calculate some test statistic (say the Pearson correlation), and estimate its significance. The pvalue is calculated by estimating the ...
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1answer
42 views

How can high p-value'd variables be described in regression analysis for paper's conclusions?

In my regression analysis, I have 1 dependent and 5 independent variables. The analysis showed that fifth independent variable's p-value (Sig.) is 0.734, which is 0.05, thus statistically ...
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15 views

Selecting best model in GLM logistic with AICc, p-values for best are insignificant?

I have one potentially causal predictor and a number of covariates that I tested via AICc model selection in logistic GLM. I found that alone, the causal predictor has a low AICc (~19) and a ...
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0answers
15 views

How does max T work: an example

I am trying to permute data and return a maxT p value to adjust for FWER. I have an example of data: ...
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9 views

Interpretation of MacKinnon test of non stationarity

The MacKinnon test (see on the picture I posted) is used to know if your model is stationary or not, is that right? Here the p-value (0.3447) is greater than all the critical values, so I reject H0 ...
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Drawing one-sided conclusions from two-sided tests? [duplicate]

In the Vickers book, 'What are p-values anyway?' there is a question about whether a "scared straight" program has an effect on juvenile incarceration rates vs a control program. The null hypothesis ...