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A test (typically of distribution, independence, or goodness of fit) or a family of distributions related to such a test.

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What exact statistical method should I use to compare two samples of targeted DNA sequencing?

I have results of targeted sequencing. It is several csv files (tables) with information about the identification number of amplicon (in two samples there are equal number of amplicons - 202) and ...
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2answers
34 views

Negative Values in G test

I have a question, that regards the G-Test. This, as defined by Wikipedia to use $$ G=2 \sum \limits_{i=0}^n O_i\ln(\frac{O_i}{E_i}) $$ as a value to measure the observed samples $O_i$ of category $...
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13 views

.In Eviews, wald-test and F-test [on hold]

Why is the Wald test presented together with the F-Test in this regression output from E-Views?
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1answer
25 views

Should I use logistic regression, chi-squared, or something else?

Let's say I ran an experiment where 100 people performed 4 identical tasks (Task 1-4) on two different software packages (Package A vs. Package B) such that I have 8 trials-worth of data for each ...
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1answer
23 views

Statistic test to prove if there is a difference between A and B from answers A>B, A<B and A=B

The conducted test allow participants to respond with the following three answers: - a) A is better than B (A > B) - b) B is better than A (A < B) - c) A is equal to B (A = B) The first approach I ...
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29 views

z-test of proportions vs chi-squared

A 2-sample z-test of proportions and a chi-squared test can both be used to analyze a $2\times 2$ contingency table. In fact, for $2\times 2$, $\chi^2=z^2$. Why can the same table, being used with two ...
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0answers
16 views

Correlation between Ordered Variable and Categorical Variable

I am analyzing Opportunities for Sales people. I have a categorical variable which is Status:{Won,Lost} My dependent variable, and other Independent ordered variables like the stages of the ...
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0answers
9 views

Chi square for comparing more than 2 categories

I did a retrospective study on complications after 2 types of surgery. My data is catagorised by subtype of complication (bleeding, infection, nerve damage, ...). Can someone tell me if I can ...
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15 views

2 sample CHI SQUARE test for continuous data

'm facing a unique (at least for me) analysis task and I'm confused about the proper way to conduct statistical test. I'll describe the problem first, then suggest how I think it can be solved and - ...
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0answers
10 views

Testing if word-count vectors follow a multinomial distribution

I am attempting to make a Naive Bayes classifier for word count vectors (each document is represented as a vector of word counts). For this, I am using SciKit-Learn's MultinomialNB. From what I ...
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1answer
28 views

Chi-squared test simulation significance threshold

I have asked question on CV here so this is a follow up. I believe this time I have the chi-squared test correct. In this example I'm simulating o (observed ...
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1answer
28 views

How to minimize Chi-Square using the CDF instead of the PDF?

Suppose one has data that is suspected to obey a normal distribution. One computes a histogram of the data, and performs Pearson's Chi-Squared Test. To perform this test, one must compare the observed ...
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25 views

Fisher's exact test with opposite direction of categories for two groups

I would like to analyze student performance under two teaching approaches for two classes. We predict that class 1 would outperform class 2 and ideally the performance between two classes should be ...
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1answer
32 views

Chi-squared test on small number of groups and large observations

I'm comparing two data sets (3 groups) with relative large number of observations and I'm getting p-value of 0. (0 < 0.05, meaning rejecting H0, that the samples are equal, when in fact there is ...
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2answers
39 views

Contingency table (2x4) - right test & confidence intervals

I have 2 categorical variables for each observation in my dataset: environment and behaviour. I'm trying to test association between them i.e. does the environment affect behaviour? The resulting ...
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0answers
16 views

How to analyze the frequency of correct/ non-correct answers

I have a question about how to analyze some data. It involves the performance of two equally sized groups in a questionary with 30 arithmetic questions that I scored with two possible outcomes (...
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0answers
24 views

Feature selection using chi squared for continuous features

I'm looking at univariate feature selection. A method that is often described, is to look at the p-values for a $\chi^2$-test. However, I'm confused as to how this works for continuous variables. 1. ...
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17 views

How can I interpret the chi-square plot from Benford.Analysis R package

When you plot the results after applying the benford.analysis R package, I get the following plot. Here is the full set of plots that I get when using the package. I have not idea how to interpret ...
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39 views

7-point Likert scale

I have about 19 participants in a training program. I am trying to study the attitude which it consists of three components: affective, cognitive, and behavioral and see how it can predict their ...
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1answer
16 views

Prove positivity of chi-squared statistic with general covariance matrix

For a "simple" chi-squared test statistic $\chi^2 = \sum_i (x_i - \mu_i)^2 / \sigma^2$, it's clear that the domain is positive since both the numerator and denominator of every term in the sum over ...
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1answer
28 views

Log-linear regression preferred over logistic regression for categorical vars?

I read here that, when all variables are categorical, log-linear is preferred over logistic regression "because log-linear is merely an extension of the chi-square test." I don't have a stats ...
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1answer
76 views

Why does Logistic regression doesn't give the same result as a Chi square test when testing difference of frequency with more than 2 groups?

I have data that looks like this: there is a group of 27 subjects with one dichotomous variable $y_1$ at 3 times points. The propbability of $y_1$ is different between the 3 time points (100%, 85%, ...
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21 views

Chi-square test of independence or test of homogeneity

I am new to Chi-square tests. And after looking at some examples in my textbook, I wonder if test of independence and test of homogeneity are the same. This is an example in my textbook which use the ...
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25 views

Which test to use to detect difference in proportion between more than 2 groups? Logistic regression?

I have data that looks like this: there is a group of 27 subjects with one dichotomous variable y1 at 3 times points. The propbability of y1 is different between the 3 time points (100%, 85%, and 40% ...
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1answer
36 views

Can I perform a Chi Square test comparing the one year mortality of my 160 patients versus the 108000 patients of a cohort in the litterature?

I have exactly zero experience with statistics. I was interested in comparing 1 year mortality of patients $\ge$ 60 years old versus $<$ 60 in a cohort after a specific intervention. I performed ...
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24 views

sub-exponential property of a linear transformation of independent random variables

I need to use a Bernstein-type bound to a random variable $y^Ty$, where $y= Qx$. $x$ is a Gaussian vector where each entry is independent. $Q$ is a kernel matrix. So $y$ is the linear transformation ...
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28 views

Binary logistic regression with coupled independent variables?

I'm new to Logistic Regression and need to determine whether its valid for independent variables that are strongly coupled. Investigating, I created a fictitious sample set of sports fans to test the ...
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0answers
13 views

ANOVA, mutual information, Chi-squared feature selection are widely used and implemented in SKLearn - but where were they first published?

SKlearn is a widely-used, almost 'industry-standard' package for machine learning and implements a number of univariate feature selection methods (ANOVA, mutual information, Chi-squared) ... but the ...
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1answer
29 views

Reproducing this chi-square probability from published work

So i'm working on a Greenhouse-Geisser correction and i found this "John, Nagao & Sugiura’s test for sphericity" in this publication (https://www.utdallas.edu/~herve/abdi-GreenhouseGeisser2010-...
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56 views

$\chi^2$-test for smoothing splines: degrees of freedom

Suppose we are given raw data, e.g. raw mortality rates $\widetilde{q_x}$, which are graduated by a smoothing (cubic natural) spline $S$. That is, we obtain smoothed rates by setting $q_x:=S(x).$ Let ...
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0answers
14 views

Formal Definition for Chi-Squared Test for outliers

I am looking for a formal definition of the Chi-Squared Test for outliers. I have searched for one, but cannot find one. I am interested to know what others use as well as where they got it from. ...
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8 views

Chi-Square for reducing 'insignificant' variables in nominal data (Social Sciences) and interpreting Phi

I'm looking for validation as to whether this is the best approach to pair down the number of variables I'm working with, or suggestions if not. I'm working with a fully nominal (mostly binary) data ...
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21 views

Correlation coefficient on binary variables

I have two binary variables and want to test their association. From what I've read I need to use the chi-squared ($χ^2$) test. The measure of their association is then described through the Phi ...
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1answer
24 views

Is a chi-square test for independence appropriate on a contingency table where one category is the unsupervised learning cluster?

I have a data set that has been partitioned into four clusters by executing a clustering algorithm that used principal components from a principal component analysis (PCA). I then make a contingency ...
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23 views

Chi^2 Test: Alpha and it's Relation to Sigma

I'm using an Extended Kalman Filter and the $Chi^2$ test to test a part of it's residual during the update. Here I want to determine if the residual lays within 3 Sigma and reject outliers that are ...
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0answers
8 views

Mantel Test of Proportion : Aggregating categories different significance

I have a dataset representing for a specific marketing event editions (1 event per 1 year), the number of partecipants, and the outcome of their partecipation If In sas I use the Mantel Exact test to ...
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34 views

Why do Chi-Square distribution and Poisson look similar

I am new to statistics and I am looking at Chi-Squared distribution, and I found this looks similar to Poisson distribution. Is there any theoretical relation between them, or its just coincidental? ...
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20 views

Chi-square test for image encryption

I have a cipher image $C$ that has intensity levels between $0-255$. I want to check this cipher image for uniformness. For this, I calculated the Chi-square tests. The $\chi^2=270.2112$ and i know ...
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1answer
17 views

Find if two groups are different where one is a subset of the other

I have a dataset of 3,500,000 categorical observations that can be grouped by an ID. In these categories u occurs 25,000 times. How can I test to determine if a ...
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1answer
25 views

P-value and confidence interval in MVT testing

Context: website A/B testing When calculating P-value and confidence intervals for each variation in an experiment with more than 2 variations (control, variation 1, variation 2 ...) should there be ...
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1answer
67 views

test of two proportions

Apologies for an elementary question - I am trying to understand the solution to the following problem: "Suppose interviews were conducted at two different shopping centers. This two sample t-test ...
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2answers
42 views

test for significant for more than 2x2 consistency table

I have some ratios like this: TumorType Positive_Test Total X 87 96 Y 112 124 Z 92 147 I want to test whether there is a significant difference in the column <...
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0answers
18 views

Is it valid to compare Chi-squared statistics for the goodness of fit to different distributions?

I have observations on a variable and I would like to know which probability model describes the data the best.. Can I just fit 2 models, and choose whichever gives the lowest chi squared statistic ? ...
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1answer
29 views

Normalization the data before applying statistical test for large sample size

From my perspective, the reason p-value of a statistical test isn't useful in large sample scenario is because it will change according to the scale. E.g. let's focus on chi-square test. In a chi-...
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1answer
51 views

Distribution of the sample variance of values from a multivariate normal distribution

What is the sampling distribution of the variance of a collection of variables that follow a multivariate normal distribution? Specifically, assume that the $n-$dimensional vector $\boldsymbol{x} \sim ...
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0answers
14 views

Will the small proportion ruin the ability of chi-square test? [duplicate]

Let me raise an example to be clear: say I have a 2*2 contingency table as follows: 5 10 10000 10000 I assume it satisfies the assumptions of chi-square test. But the proportion ~ 0.05% is very ...
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1answer
43 views

Appropriate strength test of the chi-square test for large and unbalanced data

I understand different statistical tools have their own pros and cons. I'm trying to find the most appropriate one for my situation. I have a large, unbalanced data set and want to implement the chi-...
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17 views

Log-linear analysis versus independent chi-squares result

I am analyzing a number of categorical variables, and used log-linear modeling in SPSS to see whether there is association between any of them. I have some variables, however, which turn out to be non-...
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41 views

Chi-square test and Somers' d

I have two ordinal variables. I would like to know if there is a dependency between these two variables and also how strong this dependency is. So, I performed a chi-square test (34.53, df=8) where ...
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1answer
16 views

Chi2/ANOVA testing on sets of much different size

I am trying to decide on which stats test to use to determine if the number of males/females is higher on people who decided to buy a product versus those who didn't buy a product. 96000 people didn'...