# Questions tagged [p-value]

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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22 views

### How correction for p values work in case of multiple comparison?

This is a very basic question. I want to conduct post-hoc comparison using a fitted mixed model. emmeans(model, pairwise~condition) ...
11 views

### How to test that there is no interaction between two factors?

Using a two-way ANOVA, I can test three null hypotheses: The means of the response variable are equal for different values of the first factor. The means are equal for different values of the second ...
23 views

### Correction p-value with the Bonferroni correction

I have done an analysis using SPSS. I would like to compare the situation before and after treatment in the same patient, so I used the Wilcoxon test (not normally distributed). Now I look at 3 ...
9 views

### Features backward elimination statsmodels OLS when considering interactions

I have a multi linear regression problem, $Y$ is my target and $X_1, X_2, X_3$ are my features. In my regression, I consider the interaction between $X_1, X_2, X_3$ and I add a bias. So my problem ...
56 views

### Statistical test one observed value compared to multiple values from permutations

I have a dataset set with 1 observed real value (a number of hits of various kind at given genomic coordinates within a given window of a fix size). The biology is such that repeating the experiment ...
14 views

### Does it matter if the grid search model's coefficients has a large p value?

Suppose I have a time series, which I use SARIMA to model it. I use the grid search mechanism: iterate (p,d,q,P, D, Q, 12) values over a range and rank the parameters according to the AIC values. ...
15 views

### After the linear regression on the main predictors, how to include the interactions of them?

I'm currently using R to do a multiple linear regression with 7 main predictors. I've already completed the first step of regressing the dependent variable onto those main predictors. ...
37 views

### Intercept with parameter estimate 0.0000 and p-value 1.0000. Interpretation/meaning? [closed]

I get the following information from an estimated model: ...
38 views

### Compare p values of ANOVA and $\chi^2$ test

I have dataset with different types of features (numeric/continuous and binary). Altogether 66 features. I want to find a small subset of features that is sufficient for a multi class classification ...
33 views

### Is the $p-$value uniformly distributed in this case?

Let $(Ω, A,P)$ be a statistical model, $H_{0} = \{P_{0}\}\subseteq P$ a simple null hypothesis, and $H_{1} = \{P_{1}\} ⊂ P$ a different simple alternative, so that $P_{1}$ with respect to $P_{0}$ has ...
22 views

### How to compute p-values from modified z-scores (Iglewicz & Hoaglin) for FDR correction?

I have made good experience with using the modified Z-score for outlier detection in approximately normally distributed data, which was also discussed e.g. here and here. However, if applying many ...
16 views

### Can we exclude non-significant variables (p>0.05) in ridge regression?

As far as I know, variables with p>0.05 are non-significant for the regression model. I found similar questions here about p-value like: What is the meaning of p values and t values in statistical ...
22 views

### Repeated measures anova p-value not improving with larger sample size

CONTEXT: I have an experiment of 2 groups of 20 individuals each (40 people total). The test group received an intervention to aid them in converting leads and the control group did not. GOAL: I'm ...
60 views

### Are p-value and Bayesian probabilities equivalent when applied to conversion rates?

For evaluating AB-tests, one can use the frequentist approach or a Bayesian one. Using these websites I compared both with some example data: https://abtestguide.com/bayesian/ https://abtestguide....
41 views

### 2 elements of research. significance level 1% vs. 5%. different how?

If there are 2 results / elements of research who carry a p-value (based on a paired t-test), which tests some null-hypotheses, and one part of the research (some measurement which is 0.593 ...
19 views

### Correlation one-sided p-value

I want to test a directional correlational hypothesis in the form of: H0: There is a positive correlation (𝜌) between X and Y: 𝜌 > 0. Context: The ...
17 views

### Likelihood that a group of NFL teams have a certain number of All Pros at any given position?

Over the past 20 years, 12 Super Bowl winning teams (60%) have had at least one player from its defensive front 7 selected to be All Pros. Three of those 12 teams has had two players selected to be ...
181 views

### Does p-value ever depend on the alternative?

Our tag definition of the $p$-value says 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 ...
25 views

### How to report the results of a glm from R in a scientific paper

Say I have the following results from a glm (gaussian distribution) in R: ...
26 views

There is a question in my study group that we would like some help answering: In a trial that was conducted the P value was calculated as 0.05 exactly. What are the chances that if the trial was ...
45 views

### Should I trust AIC value or the p-value of linear regression model?

I have a linear model and when i run the stepwise variable selection, i got: ...
210 views

### Bernoulli distribution p-value shortcut

I am trying to evaluate the impact of a hypothetical treatment that has a binary outcome (adverse health event or no event). I have ten thousand of simulated "studies". I want to quickly identify ...
59 views

### How important is p-value in Machine Learning?

Scikit-Learn doesn't exhibit the p-values for your models. I'm used to look at the p-values - besides a few other factors - when choosing the variables to consider on my final model. However, p-values ...
33 views

### p-values near 1.000 for all tests in a glm() (count and binary data, Poisson and binomial distributions)

I want to run multiple GLM's to answer a few questions about changes in diet between species and over time. Questions: Does frequency of occurrence (FO) of pieces eaten differ between species or ...
140 views

### statistical significance for non linear data

I have a data-set with two independent (continuous) variables: temperature (1, 3, 6 degrees) and nutrient concentration (~ 9-1400) and one dependent variable (length), with replicates (three ...
113 views

### Why is the p-value so low here?

I have the following code using statsmodels ...
146 views

### p-value generated with gam() is significant with randomly generated data - why?

I'm investigating the effect of overhead cover (tree canopy) on the proportion of birds scavenging on carcasses left out in nature. These data are taken from different national parks with different ...
42 views

### Benjamini-Hochberg procedure with equally ranked p-values

I struggling with Benjamini-Hochberg correction due to equally ranked p-values and I would gladly appreciate some help. My problem is as follow: I've got 11 comparisons to do and the threshold is set ...
13 views

### May each parameter's test statistics in regression be related to different distributions?

When I run a linear regression, the parameters are all tested whether they're zero using t-test. In some other regression, all parameters are tested whether they're zero using z-test. Is there some ...
155 views

### Why are p-values probabilities rather than likelihoods?

The p-value is the probability of obtaining test results at least as extreme as the results actually observed during the test, assuming that the null hypothesis is correct. Why is the p-value a ...
47 views

### What does X²(1, N=100) =6.83, p =0.009 mean?

I am reading scientific research (Link) and stumbled upon the following notation: X²(1, N=100)=6.83, p =0.009. An explanation is given as follows: ...
59 views

### positive correlation but p value is 0.152 [closed]

I have a positive correlation but my p-value is 0.152 am I being stupid or can any help it's kinda urgent
59 views

### Is this just a consequence of Publication bias or has a name of its own? [duplicate]

Scenario: In our world, only statistically significant ($p<0.05$) results are published, everything else is rejected or not even handed in. Let's now assume an experiment is $100$ times conducted ...
10 views

### Backward feature elimination removes significant one-sided associations?

I’m fitting data to a linear regression model. In the end, I want a model that only includes significant IVs with p values <= 0.05, so I’m looping through and at each iteration removing the IV with ...
31 views

### how can I get the P-value for each parameter in vasicek model then do the simulation in Excel? [duplicate]

I use the solver in Excel to estimate the parameter, the out put is b=0.001153,a=0.095516,sigma=0.0013. I follow the steps at https://www.youtube.com/watch?v=X17cpkkwG_4 The method is the Maximium ...
11 views

### P value significance in R [duplicate]

I understand that this p value: < 2e-16 is significant But is this p value: 1.4e-05 significant? I'm not sure how you can tell / what the 'e' means. Any help appreciated, thanks.
18 views

### Comparing time series data between three treatment groups (in R)

I have time series data where the response is decreasing over time. The rate of the decrease is supposed to depend on the treatment (the concentration of a drug). By looking at the data I am not sure ...
87 views

### What to report when p-values of Standardized and Unstandardized Beta disagree?

I am testing the following models. Volumes were purposely log10 transformed to examine brain allometry. ...
53 views

### R Displaying Incorrect Significance Level?

In the following output, predictor variable has a p-value of 0.001809 but is indicated to be significant at the 0.001 level as it has '**' displayed next to it. Surely given that the p-value is ...
240 views

### What should be statistically significant game score in football and basketball to say that one team stronger?

4 teams play 2 games: football and basketball. (2 games just to better understand theory) Final result of a football game is 2:1 Final result of basketball game is 101:96 What should be the result ...
45 views

### When to drop correlated features?

I have a dataset focused on binary classification with 60 features and 5k records. Am trying to 1) find the risk factors using statsmodel logistic regression (I do this because it's important to ...
40 views

### The uniform distribution of p-value under null hypothesis [duplicate]

Suppose z is a continuous random variable and follows a certain distribution We define φ(x)=p(z>=x), where x is a continuous random variable It can be proved that the continuous random variable φ(x) ...
131 views

### Why does the constant term have a P value in statistical programs?

I notice when running regressions in programs such as Stata that the constant term has a p value. Why and what does this p value represent?
102 views

### P-value calculation

I am trying to build P-value calculation within Tableau for A/B tests and found a formula. But the formula doesn't work all the time. ...
26 views

### compare correlation between two matrices

We have two algorithms that assign a score to the foreground of how well it fits the background. And we want to know which algorithm is closer to human perception. Then we collect an evaluation set ...
2k views

### Recommended terminology 'statistically significant'

Following the recent ASA and other comments on p-values and not using the term "statistically significant" what is the recommendation for presenting the results of an analysis? For example if I ...
10 views

### Question regarding p-value adjustment for multiple comparison across multiple experiment

This is my first question and it's about p-value adjustment for multiple comparison in the setting we conducted multiple experiments. We performed several viral infection experiment in specified ...
27 views

### How to get P-Values of Categorical Features?

I have dataframe which contains numerical and categorical features. I am trying to get p-values of these variables using OLS. I'm creating dummies to get p-values of categorical features. But in this ...