In hypothesis testing, the $p$-value refers to the probability of seeing a result as extreme (or more so) than the one observed, given that the null hypothesis is true. When the $p$-value is small, then there is good evidence that the null hypothesis is false, since it would make the observed data ...

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How would I find the P-Value of this data?

I have the following data (relating to consecutive months at current job): Mean: 45.4 Standard Deviation: 60.89 Sample Size: 48 I am asked to do a one-tailed test at a 1% significance level and ...
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27 views

code needed for p values in GLMM

I need to get p values for the fixed effects in the following GLMM's I ran. Does anyone know of code that I can run that will give me the p values I need? At the moment the output from the ANOVA only ...
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21 views

When using higher order terms in multivariable regression what is the effect on the P-value

I have a large dataset, lets say 500 lines of data. As a quick workaround to higher order regression I've made educated guesses about what higher order terms I would expect in my regression equation. ...
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1answer
26 views

impact on hypothesis if t-stat is equal to t-critical value for one-tail two-sample t-test? [duplicate]

I have a two-sample t-test where the t-statistic is equal to the critical t-value (at three decimal points) at a p-value of 0.05. does this mean i reject the null hypothesis or the opposite? thank you ...
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1answer
73 views

How to get P-Value when t value is less than 1?

I am doing an assignment for class and I have hit a wall. I'm not sure what to do next. Using a sample with 12 discrete elements, I am trying to test a hypothesis that the population mean is 243 ...
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15 views

Q-Value Less than P-Value

I have a list of p-values from a series of regression equations. Many of these P-values are small. To compute false discovery rate I have been using the q-value package in R. I notice, based on this ...
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2answers
102 views

How to calculate p values in logistic regression with gradient descent algorithm

In logistic regression, the gradient descent algorithm for calculating coefficients can be described this way: Until convergence, do $$ \beta := \beta + \alpha \frac{\partial L}{\partial \beta} ...
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10 views

R: Shapiro-Wilk test with relation of W and P-Value? [duplicate]

I'm currently learning about the Shapiro-Wilk test for normality and using R for conducting simple experiments. One thing which is confusing me is that I found some results would produce a high W ...
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1answer
52 views

Extracting the model p-value for a multiple regression in R

When fitting multiple variables to one outcome via the lm() function in R, summary(lm) gives me the p-values for individual ...
0
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1answer
32 views

Calculate p value for Pearson's R

I have a bunch of bivariate correlation tests for which $R$ has already been calculated. Is it possible to figure out the p-value for each $R$ knowing only (in addition) the number of data points ...
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1answer
31 views

Standard deviations and significance values

I was wondering if data 2 SD from the mean is deleted as outliers, is it possible there after to report 0.01 significance values? Thanks!
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2answers
35 views

How to obtain a p-value for the eta measure of association?

How can a P-Value be obtained for an analysis of Eta association? Is there a reference for this?
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31 views

coefficients and p-value in logistic regression

In logistic regression, I have a variable with larger coefficient and larger p-value and another variable with smaller coefficient and smaller p-value. If use p-value then the latter one is more ...
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10 views

MANOVA, when independent variable is not multi-level and P value significance variance [duplicate]

My research has 4 independent variables and 4 dependent variables. My hypotheses are constructed in such a way that 1 independent variable's effect size is checked on 4 dependent variables. My ...
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39 views

MANOVA, when independent variable is not multi-level and P value significant in MANOVA but not in ANOVA

My research has 4 independent variables and 5 dependent variables. My hypotheses are constructed in such a way that 1 independent variable's effect size is checked on 5 dependent variables. MANOVA is ...
0
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1answer
52 views

R: Setting an F-statistic to determine variables for a multiple linear regression model

I am trying to understand the steps behind the linear regression process. I already have a linear model like: lmodel1 <- lm(y~x1+x2+x3, data=dataset) for which ...
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3answers
218 views

Relative size of p values at different sample sizes

How does the relative size of a p value change at different sample sizes? Like if you got $p=0.20$ at $n=45$ for a correlation and then at $n=120$ you got the same p value of 0.20, what would be the ...
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27 views

Confused about how to work through this t-test problem

So, I'm working on this homework problem and am really unsure how to go about it. I'm working with an online software, which gives me the answers to the questions, but I have no idea how to get to ...
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1answer
63 views

P-value of F-test to compare two variances (var.test in R)

I am trying to understand where the p-value of a F-test comparing two variances comes from. More specifically, the p-value given by R's var.test function does not ...
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2answers
64 views

How to compare two non-normally distributed samples with very different sizes? (Mann-Whitney vs Randomization/Bootstrap)

Perhaps this is a very basic question, but I didn't find yet a simple solution for this simple problem: I want to compare two samples (say X and Y) for a continuous variable which is non-normally ...
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If the distribution is bimodal, does p-value mean anything?

P-value is defined the probability of obtaining a test-statistic at least as extreme as what is observed, assuming null-hypothesis is true. In other words, $$P( X \ge t | H_0 )$$ But what if the ...
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1answer
85 views

Binomial GLMM with categorical predictors: p-values?

My data has a binary response (correct/incorrect), one continuous predictor score, three categorical predictors (race, ...
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32 views

Binomial mixed model with categorical predictors: model selection and getting p-values [closed]

My data has a binary response (correct/incorrect), one continuous predictor (with NaNs) and several categorical predictors. I want to add a random intercept for a ...
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24 views

How to test a Random Number generator in R? [duplicate]

I have a random number generator of U(0,1), I apply the ks test on x, which has 10000 random numbers in [0,1]: > ks.test(x,"punif") and obtain this result: ...
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44 views

how do I “build” a distribution from a list of values and then calculate p-values?

I have a list of values (A) that I consider to be the null distribution which I want to use to test the significance of another set of values (B) and get p-value for each item in B. I read this post ...
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1answer
119 views

Equivalence of AIC and p-values in model selection

In a comment to the answer of this question, it was stated that using AIC in model selection was equivalent to using a p-value of 0.154. I tried it in R, where I used a "backward" subset selection ...
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1answer
52 views

Are these statements about p-values correct?

I've seen the following equivalent statements about p-values: "It is the probability of wrongly rejecting the null hypothesis if it is in fact true." [1] "The P value or calculated probability is ...
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55 views

p-Value of mean of sample means

I suspect this question is related to: When combining p values, why not just averaging? Let me explain my problem: Suppose you have a set of sample means and associated p-values, standard errors ...
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29 views

the correlation between the correlation and T-value of tens of group

I have run correlation tests between two city-level variables (e.g. weather and revenue) from about 30 different cities, and therefore got 30 pairs of correlation and T-value by cities. My hypothesis ...
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49 views

Is the p-value equivalent to the false alarm value in the Bayesian rule?

Is a p-value from a traditional significance test the same as the false alarm value in the Bayesian rule? And/or is it "close enough" to give correct results when used that way? The definitions of ...
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370 views

Why are 0.05 < p < 0.95 results called false positives?

Edit: The basis of my question is flawed, and I need to spend some time figuring out whether it can even be made to make sense. Edit 2: Clarifying that I recognize that a p-value isn't a direct ...
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1answer
5k views

Explain the xkcd jelly bean comic: What makes it funny?

I see that one time out of the twenty total tests they run, $p < 0.05$, so they wrongly assume that during one of the twenty tests, the result is significant ($0.05 = 1/20$). xkcd jelly bean ...
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52 views

Afex does not give me all p-values of all parameters. What should I do?

I have installed the package afex with this formula: ...
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41 views

pvals.fnc does not work with random intercept and slope. How to get p-values?

I am doing LMM in lme4, and have installed languageR to run pvas.fnc(), but it does not work with random intercept and slope. This is the message: ...
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How to get p-value for fixed-effects by model comparsion?

I am doing linear mixed model using lme4. According to Winter (2013, http://www.bodowinter.com/tutorial/bw_LME_tutorial2.pdf), as the new version of R does not give p-values due to inconclusion of ...
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41 views

Does filtering of data by effect size violate some assumption of P value adjustment methods?

I have pre- and post-treatment continuous data for a large number of variables that I am analyzing for treatment effect. Normally I would obtain the P values and then adjust them for multiple testing ...
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1answer
32 views

Why isn't this code for prop.test giving me the right answer for test statistics?

I have used the following line of code but it doesn't give me the right answer for (chi-squared) test statistic while it gives ...
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81 views

Statistical comparison of data dispersion between two groups

I was trying to find a suitable way to compare the relative data dispersion between two groups and also to investigate if they are statistically significant. During the last weeks, I have searched a ...
5
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3answers
112 views

What is the effect of having correlated predictors in a multiple regression model?

I learned in my linear models class that if two predictors are correlated and both are included in a model, one will be insignificant. For example, assume the size of a house and the number of ...
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29 views

Bonferroni correction: control vs. groups?

I'm trying to understand how to set up a Bonferroni correction on several different groups and compare it to the control group. The groups and observations are as follows (with Group 0 being the ...
2
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1answer
71 views

Help in understanding how to apply correctly False Discovery Rate adjustement

I am trying to understand how to correctly apply False Discovery Rate when comparing multiple hypothesis tests. Although I use here R code, my doubts are about the procedure, rather than the ...
0
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1answer
101 views

Compute p-value of single value in arbitrary distribution (using java and apache.commons.math3)

I want to compute the p-value of a single numeric value drawn from an arbirtary distribution. The p-value should be comparable to p-values that have been computed with single distinict values drawn ...
4
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1answer
64 views

Non-normal residuals - P-values higher or lower?

Background: I have estimated a model using panel data with the Arellano Bond estimator (see e.g., http://www.fordham.edu/economics/mcleod/Elitz-usingArellano%E2%80%93BondGMMEstimators.pdf) and n=300. ...
3
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1answer
53 views

Comparison between Log-likelihood ratios and beta coefficients

I was asked a question recently which I could not find an answer for and was hoping someone could enlighten me. The question was regarding the significance of a single variable in a linear model. ...
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Maximum power test

Question: In a count that was held a year ago in a reserve , there were 15 tigers counted. 7 females and 8 males, which were marked with numbers from 1 to 15. a. By recent reports, there was fear ...
2
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1answer
41 views

P-value verification

Question In some bank, the time it takes from the moment a customer arrives until a clerk is available is distributed normally with $\mu=15,\sigma=2$ a. What's the probability for the next client to ...
4
votes
1answer
48 views

Probability of choosing N out of K correctly from a total population of X [duplicate]

Out of a total population of 50 items, there are 20 "correct" items, what is the probability of me selecting 11 (or more) of these correct items if I randomly choose 20? How can I do this in R? I ...
2
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3answers
167 views

How to obtain p-values of coefficients from bootstrap regression?

From Robert Kabacoff's Quick-R I have ...
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Alternate interpretation of p-value [duplicate]

I have got a p-value of .0166 on a hypothesis test on comparison of hourly wages for different countries. Would it be right to make a a conclusive remark that “We can be 98.34% confident [1-.0166] ...
2
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1answer
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Bootstrapped p-value

I have a p-value that I generate via resampling. Resamples = 5000 Positive findings = 1000 positive findings P-value = 1000/5000 = 0.2 How can I compute the 95% confidence interval for this ...