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Questions tagged [hypothesis-test]

Functions used to choose between competing hypotheses about one or more probability distributions. For statistical questions, please use stats.stackexchange.com.

Common hypothesis tests include the one-sample and paired t-test for means, the z-test, which approximates the t-test for large samples, F-test for differences in variance, and Chi-square test for independence, and Fisher's exact test for differences in proportion.

Please note that this tag is totally different from , which refers to software testing.

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Multiple Hypothesis

I want to simulate two sets of data from multivariate normal distribution with some mean vector and covariance matrix. I want N(=3000) simulation with n(=30) number of values for each of k(=100) variables. So there will be two sets of 100 variables…
user179439
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When is Multiple Comparison Correction necessary?

I am not very experienced in hypothesis testing and have a problem understanding when Multiple Comparison Problem occurs? As I Understood Multiple Comparison Problem occurs when one tries to perform several statistical tests from a single…
Shirin Najdi
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Testing CSR on lpp with R

I have recently posted a "very newie to R" question about the correct way of doing this, if you are interested in it you can find it [here].1 I have now managed to develop a simple R script that does the job, but now the results are what troubles…
Alberto Mnemon
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Type-II error in Hypothesis Testing

I am new to Statistics and was reading about Decision errors in Hypothesis Testing. My question is that why is Type-II error an error at all? From what I understand, it arises when we fail to reject a false null hypothesis. When we fail to reject…
Sanket Kedia
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R: Error in hypothesis tests in nested data frame

I have been getting error messages when trying to do hypothesis tests, like T or Wilcox tests, on nested data. This is all code that previously worked until recently. (I wonder if it could be related to the dplyr .7 update?) For example, ID <-…
user42485
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Default p-value obtained in R

In R when I use the chisq.test() function, what is the p-value that is computed? Is it two sided, upper tail or lower tail ? Thanks in advance for helping out this beginner
Tejkiran
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Normality test for polynomial regression

In R, I used polynomial regression for the database below. It shows that the R2 is good and both the significance level for the coefficients and the model are less than 0.05. But when using the shapiro.test for testing residuals, the p-value is…
mcxmcx
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why we need tf.arg_max(Y,1) with softmax in tensorflow?

when I write the tensorflow demo, I find this arg_max() function in the definition of correct_predition cost = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits( logits=hypothesis,labels=Y)) optimizer =…
Hong Cheng
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How to run leveneTest for 5,834 genes at the same time

We have 35 mesenchyaml stem cells (MSCs) single-cell RNA-Seq data, and would like to compare gene expression heterogeneity between different culture conditions (i.e. hypoxia and normoxia). In other words, We would like to identify genes that are…
Gary
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R - Hypothesistests - How to interpret output?

I have an assignment to test out some hypothesis... To simplyfy this, lets say there are 433 out of 1044 and I have to check whether the rate increases or not / differs from 23%. null: rate <= 0.23 alternative: rate > 0.23 I did choose a…
HappyR
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R: Durbin Watson test with NA result

I am trying to gauge the correlation between the historic of a stock price and an index using the Durbin Watson test in R. This is what I have done so far: data <- read.xlsx("data.xlsx", colNames = TRUE, detectDates = TRUE) data head(data) data$X1…
Alejandro Jiménez Rico
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Robust one-sample tests of variance or scale

A common one sample test for variance is the chi-square test, e.g., http://www.itl.nist.gov/div898/handbook/eda/section3/eda358.htm. What are some robust testing alternatives for variance when the population is not normal and/or is subject to…
rhz
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R:hypothesis testing for panel data

I have a panel(5x5) that has mean values of ice-creams consumed per day for 5 years and 5 persons. I want to conduct a hypothesis test that mean=50 for this panel. Please help do this in R. I have no clue how to proceed so I have no sample code.…
Polar Bear
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Determine sample size for A/B testing, more than 2 variants

What R function should we use if we want to decide the sample size for such a test: 10 ads, we want to use a test to decide which ads has the best click through rate. We are able to count the flow and click throughs.
StayLearning
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Calculating a t-test in Stata

I am currently trying to run a t test on a variable and determine if it's statistically significantly different from 1. Here is the code I am using: ttest dm1=1 And it is spitting out this output: I don't want my null hypothesis to be that mean=1,…
user4378398
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