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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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How do I calculate a simple one-sample t-statistic in Scala-Spark in an AWS EMR cluster?

I'm a data scientist and still relatively new to Scala. I'm trying to understand the Scala documentation and run a t-test from any existing package. I am looking for sample Scala code on a dummy data set that will work and insight into understanding…
user2205916
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weightstats.ztest vs hand calculation

I am comparing my z-score result from weightstats.ztest and hand calculation and get slightly different result, z_package=-12.636 and z_handbook=-13.019. The z_package is determined by z_package, p = weightstats.ztest(data1, data2) were sample size…
Alex K
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I want to validate the hypothesis that trend follows from social to search to sales

I have three datasets with me. Social , Search and sales dataset. I have to validate the hypothesis that trend follows from social to search to sales. I am also asked to find the latency and if the latency is same among all the theme ids. I am also…
Dinesh Sivasankaran
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Can I use hypothesis Testing on Train and Test data?

I was wondering if I could use Hypothesis Testing against trainning and testing data, after splitting my dataset. My objective is to check if both of the data samples group are well balanced, distributed and so Will provide a Nice environment for…
jaymzleutz
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Understanding Chi Square test on Titanic dataset

Currently I am working on Hypothesis Testing on datasets. While reading about chi square tests I found this notebook through…
ApaarBawa
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Bayes Factor as non-logistic output from proportionBF

I am estimating a BayesFactor of proportions using the comand proportionBF() from R. I want to replicate the example from wikipedia https://en.wikipedia.org/wiki/Bayes_factor. The output from the proportionBF comand is in log, so I transform the…
Ushuaia81
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How to compare daily active data to cumulative data?

so I am working on COVID-19 data of the state of Texas, USA. I have been given 2 hypotheses to work on A higher hospitalization rate gives a higher fatality rate A higher ICU rate gives a higher fatality rate. Fatality Data -…
Jaimin Brahmbhatt
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Stata help: null hypothesis against the alternative hypothesis

How can you with Stata test the null hypothesis against the alternative hypothesis. If I have the hypothesis H_0:\beta_1=\beta_2=0 against H_A:\beta_1 ≠ \beta_2 ≠ 0. What will the code be?
Lifeni
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Hypothesis test in scipy

I'm using SciPy to perform Wilcoxon test and Friedman test. For example, I have 3 groups of samples. sample1 = [0.76623377, 0.77922078, 0.71428571, 0.63636364, 0.7012987, 0.66233766, 0.72727273, 0.67532468, 0.63157895, 0.77631579] sample2 =…
Helen
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Mood median test for equality of distribution in R?

I do have a<-rnorm(10,0,1) b<-rnorm(10,3,1) i want to test the follwing hypothesis " they are equals there is no shift " against " the second a shifted from the first" I searchd for median test wwhich used the numbers of values graters than pooled…
Z B
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calculate power for one sample one sided ttest

I have the code below that I'm using to try to calculate the statistical power of detecting an effect size as large as the one below, with the given sample size. I'm calculating power for a one sample ttest with the alternative hypothesis that the…
user3476463
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Is there a way of classifying a set of curves into two or three groups?

I conducted an experiment, in which participants (n=44) experienced different tones ranging from low to high (x-axis) and rated their perceived liking from 1- low to 10 - high(y-axis). I created line charts for each participant. Just by looking at…
AEdelstein
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Regarding chisq.test (x, p) function for goodness of fit, how does R tell the degree of freedom of chi-square?

If I test x against a Poisson hypothesis, then I use mean(x) as lambda to calculate p so df = k - 2; if against a Normal hypothesis, then I use mean(x) and var(x) to calculate p so df = k - 3. How can R return a chisq value without knowing the df…
limestreetlab
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T test in r: How to change the x and y arguments of a t-test using a lapply function

I have this dataframe: I'm performing a t_test using this lapply approach: columns = colnames(my_data)[-1] my_t_test<-lapply(my_data[columns], function(x) t.test(x~my_data$Treatment,alternative='less')) But it seems the t_test take…
David López
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How to test linearHypothesis on intercepts of polr ordered logit model?

I want to test for significant differences of the intercepts in an ordered logit model. library(MASS) house.plr <- polr(Sat ~ Infl + Type + Cont, weights = Freq, data = housing) summary(house.plr)$coefficients # Value Std. Error t…
jay.sf
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