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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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running paired wilcoxon test on rows of two dataframes

I have a two large dataframes (around 19000 rows and 71 columns) as…
sherbman
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ImportError: Failed to import test module: Django Tests

I have written some tests for model, views and serializer. All tests are running fine except for the serializer tests. Creating test database for alias 'default'... System check identified no issues (0…
Innomight
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F-test with complex survey designs (R)

I would like to perform an F-test on the equality of variances between a a sample conducted with simple random sampling, and one which incorporates weighting and stratification into the survey design. Several days ago, I asked a similar question…
Nate
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When doing a t-test with t.test() while piping, what does the period do in "data=."?

I have a data frame with 2 columns being age and sex. I'm doing statistical analysis to determine if there's a difference in the age distribution in the two groups of sex. I know that if I don't call data= it will give an error (I believe it's…
AvocadoFishy
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Statsmodels F-test for joing significance of lags

The following page gives an example of f-test in statsmodels: f_test >>> import numpy as np >>> import statsmodels.api as sm >>> data = sm.datasets.longley.load() >>> data.exog = sm.add_constant(data.exog) >>> results = sm.OLS(data.endog,…
Djpengo
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weighted kolmogorov-smirnov-test for single variable

Kolmogorov–Smirnov test KS can be done for the single variable as x <- rnorm(50) ks.test(x, "pnorm", mean=mean(x), sd=sd(x)) Results: One-sample Kolmogorov-Smirnov test data: x D = 0.057841, p-value = 0.9927 alternative hypothesis: two-sided How…
ForestGump
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Q-Q Plot - Split one plot into 2 groups

I have a data set, in which I am trying to fit a regression model for the Y axis - which has 35 rows. Before regression, I am running a Q-Q plot to see if the data is normal, but instead my data is following two trends in the same plot, which means…
Sibangi Bhowmick
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Is there a way to change the significance level (alpha) in R?

Im trying to perform a simple hypothesis test but now I need t-values for alpha = 0.01 instead of 0.05 (the default). Is there a way to do this in R? This is what I am trying to get for alpha = 0.01: enter image description here
Yellow SIngh
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Purposes of two-sided/one-sided specific while testing independence with Fisher's exact test, Chi-square test

I'm struggling to understand the operation behind Fisher's exact test & Chi-squared test. As I understand, both of the tests do the same thing that is to test for the independence between 2 categorical data. For example, I have the contingency table…
NganKD
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How to test the significant difference between measured value matlab?

I have an Output sample for electronic components and I would like to know the p-value for robust my system is. Ideally, I would like to get a p-value (P<0.05) to prove that my system can constantly produce the same results. Noting, my data samples…
Anwar Elhadad
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Multiple t-test on independent group with a large dataframe

I've seen many similar posts but the vast majority of them are at least 3 years old and I'm not really sure they apply to my situations, so here we go. A colleague asked for my help on a multiple t-test on her project. Basically she has 20…
Yo Pomdpin
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How to interpret t.test in R

I have a dataset with two variables (x1 and x2) from many firms which belong to different industry groups. I calculate the variable "test1" for about 500 firms. We are given the follwing code: df$test1 <- df$x1 - df$x2 library(broom) result.test…
newbie090909
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Hypothesis testing library unable to find a failing example for this simple arithmetic problem

I am trying to learn the hypothesis testing library for python and I came up with the following example (taken from a math channel in youtube) which is a very simple arithmetic problem: find x, y, w, z such that x*y = 21 & x+w = 8 & y*z = 9 & w - z…
Adrian
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How to perform hypothesis test in R for the mean value of y at a specified value of x

I would like to test the null hypothesis that the mean value of y at a specified x is equal to a specific value vs. the alternative that it is not equal to that specific value. How can I calculate the corresponding T value for the test statistic and…
mebby
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How do we do a hypothesis testing for continous X and Y variable

I have a dataset where I have number of hours I the student has studied v/s Marks scored. The question is to hypothesis test "students who have studied less have scored more"
tej kiran
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