Questions tagged [chi-squared-test]
A test (typically of distribution, independence, or goodness of fit), for the family of distributions use [chi-squared-distribution].
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Is it reasonable to use Chi Square data in a bivariate analysis?
I am currently working on a report about the frequency of hand types in Texas Hold'em and whether or not the frequencies change when there are multiple players involved. For example, is there a change ...
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Appropriate test for comparing categories in two groups?
I have a subset of a data as below: I would like to compare two groups (1/0) for 7 categories A, B, C, D, E, F, and G. The participants have each week (36 weeks in total) reported on reasons for using ...
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specific correlation for catagorical variables [closed]
I just wonder, can I determine the correlation for a data consisting of categorical variables. For example in school A, 300 out of 350 female students pass exam. While in School B, 100 out of 400 ...
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What is the test performed in this table?
Yesterday I was helping a friend in reviewing a clinical psychometric paper for his Bachelor's thesis. There, there is this table presented:
Now, the paper states that (the emphasis is mine):
"...
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How can mahalanobis and chi2-test be used to determine of an observation is acceptable?
Assume that you have a model
$$\dot x = Ax + Bu$$
$$y = Cx$$
And this model is SISO. Single input and single output. You got the mission to determine of an observation is acceptable for the kalman ...
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What statistical method should be use if I have a 1 x n matrix of data
I am doing some data analysis on medical data and need to know what the most appropriate statistical method to use would. the data will be for a particular disease and checking against patients HIV ...
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Chi-squared test with more than two variables, or should I run a different test?
I am looking at whether certain animals or categories of animals are more likely to use human-made trails than natural trails. We used camera traps and recorded for every case which animal it was, ...
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Definition of 'independence' of comparisons in Multiple-Comparison - Bonferroni Adjusted Standardized Residuals for Chi-Squared Test
I have provided a hypothetical example to illustrate my question. Assume an alternate hypothesis for a difference between two variables of interest (arbitrary for the example), analyzed with a chi-...
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Difference of output in Chi-square in SAS and R
Currently I have a dataset with an N of 3866 with two variables, Project (group variable, six levels) and Topbox (two levels; yes, no). We are looking to see if there is a difference in the proportion ...
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Correct statistical test to model user preferences among multiple models
My problem involves comparing the performance of machine learning models to how good each model's recommendation is.
The way I'll design the experiment is as follows:
I'll send out a form to multiple ...
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One proportion Z-test and Chi Square Goodness of Fit should be identical but return different results
My understanding is that a Chi Square Goodness of Fit test and a one-proportion Z-test should have identical p-values and be equivalent (https://youtu.be/-Vssir6yUNQ?si=4-t9Np9h4bedU9xN&t=423). ...
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Can I fit a Poisson distribution to a continuous variable to apply event detection algorithm?
Preprocessing:
I have a time series of number of tweets per 10 minutes time interval that are all taken from a given discussion on a specific topic in a specific region. I preprocessed the data by ...
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Sample size calculation for a three independent arm RCT with a categorical outcome
I have three study arms on interventions A, B, and C, which are independent of each other. The primary outcome is categorical (positive or negative). The null hypothesis is A = B = C.
From prior ...
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How to perform a chi-squared test on tables with multiple dimensions?
I want to test with the chi-squared test if there is a difference between the survival rate for each earthworm species and the flooding condition of my experiment. An example of my dataset, survival1, ...
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Comparing subgroup to the overall group, using 3 different tests for nominal and ordinal data
I have a dataset, which has different categories, such as Females vs Males, Race, Ethnicity
I also have responses - nominal (yes/no) or ordinal (from 1 to 7).
I plan to use 3 tests:
Ordinal data
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Confusion on Chi-Squared test results
Basically, I have the data where I am trying to assess whether there is any correlation between the gender of the manager and the gender of people within their team. I decided to do the chi-squared ...
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Can I move on to the next level (test) of invariance when my fit gets better?
I am running a group invariance test.
The data consists of data from students from grades 5 and 6 for one school (School A)
and only from grade 5 in another school (School B).
I have already run group ...
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How to compare a percentage of a sample to an observed population percentage, similar to chisquare
I have a sample that is randomly drawn from a population, and want to test if the distribution for a categorical variable age (under 30, 30-64, and 65+) is significantly different from observed ...
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Performing Chi-Square test (or similar) across a spatial grid
I have a dataframe in R where each row is an sf-formatted geospatial grid. For each grid, I have the number of venomous snakes and the number of non-venomous snakes seen in that area. I also have data ...
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Test if difference between two groups across 4 categories [duplicate]
I want to make a sensitivity analysis to test whether there is a statistically significant difference between the observations included for the study (n = 100,000) and the excluded observations (n = ...
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How do I understand the calculation of degrees of freedom in the context of a 2 x 3 contingency table?
I am currently reading an article, Analysis of sensory ratings data with cumulative link models. In section 2.4 - example 1, the authors describe an experiment from Bi, 2002*:
... 25 subjects each ...
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Chi-square test of association reporting in APA
Hello I'm really confused as to wether I'm reporting my data correctly.
Independent variable : expert or non-expert
Dependent variable: agreement with statement (strongly disagree, disagree, neither, ...
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Statistical test to use for study where answers are correct or incorrect
I have data from a study where participants saw an image and were supposed to judge whether it was an AI generated image or not. The Hypothesis I want to test is if they actually are able to ...
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calculate effect size from regression table
I am working on power analysis for a project. I want to benchmark effect size from another study. How can I find the effect size (Cohen's d) just by looking at the regression table below? For instance,...
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difference between two proportion in SPSS [duplicate]
The following is a toy example to help me understand how to perform test of difference between two proportions in SPSS.
I have two main geographic regions (Region 1 and Region 2) and several ...
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Curve fitting: Scaling the sigmas so that the reduced chi-squared statistic = 1. Is this a good heuristic?
In the official documentation for the python function scipy.optimize.curve_fit, the following description is given for a boolean-typed parameter absolute_sigma.
If False (default), only the relative ...
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Pearson chi squared test vs deviance test in GLM
From my understanding, both Pearson chi squared test and deviance test can be used to assess the goodness of fit for GLM, but they have different alternative hypotheses. For the Pearson chi-squared ...
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How I can establish A/B test framework?
I know that my question has big scope but I would like to get your perspective especially from statistical point of view.
I want to establish A/B framework specially for our feature tests. We are ...
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The chi-square test in Python for 3 groups of data (1 variable) [closed]
I analyse chemical data from surface water and groundwater for a scientific paper.
My data is split into three main groups: The River, row A consisting of "x" wells, and row B consisting of &...
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Making inferences from summary data: Can one relate chi squared tests to output from a Cox PH models?
This might be a silly question, but I've been asked about interpretation of a paper and have a query on how much one can ascertain without access to the raw data used, illustrated by example here. In ...
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Post Hoc for Significant Chi Square Test
I have applied Chi square test between Gender and Practice of specific norm (4 levels; Daily, Weekly, Monthly, Quarterly) to check the association.
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Can I test for a significant difference within one variable?
I collected microplastics falling on an island in a year. The types of microplastics are fiber (F) and miscellaneous (M) particles. I want to know if the number of each that fell are significantly ...
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Is Pearson's chi-squared appropriate for models with low deviance explained?
I'm working on fitting a binomial GLM using LASSO in R (package glmnet). My response variable is a proportion which is generated using count data (successes and failures). The main purpose of my model ...
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Statistical test or distance metric for comparing different distributions?
I want to compare the distributions of two different groups to determine if they are statistically different. Here is an example:
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What kind of relationship is there, if any, between simultaneous confidence intervals for multinomial proportions and chi-squared residuals?
I'm trying to understand if/how the chi-square test relates to simultaneous confidence intervals for multinomial proportions. It doesn't relate to a practical problem to solve, so this is just a ...
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How to compare U.S. Census demographic data to a population-level dataset? E.g. how to approach a question like are women underrepresented on boards?
I have a population-level dataset of all people who testified on environmental legislation in a single year. I have data on all witness's ages, races, genders, and ethnicities. This dataset is not a ...
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Chi-square for proportion/percentage of M/F in two different groups
I'm attempting to figure out how to do a chi-square based on gender in two different groups.
Overall, my data has two different groups that I'm dealing with, with a column for what drug the person is ...
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Chi Square test for repeated measures
I have a computer model simulation of a real world machine that generates either blue or red colours as output (as an example). Suppose the expected proportion of blue is 0.2 and expected red is 0.8 ...
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Regression distribution of Residuals - Chi square test
I'm trying to solve a conundrum but can't figure out where I'm making the mistake.
Let me define the Linear model as
$$
\begin{align}
y &= X \beta + \epsilon \\
\end{align}
$$
Where $...
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Inconsistent risk difference confidence interval and pvalue from Chi2-test
I am using the svyglm function in the survey package in R to compute a risk difference in proportions, 95% confidence interval and p-value. The outcome is binary ...
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Comparison of an estimated survival probability with a theorical one
My question is relative to the comparison of a probability of surviving at a fixed point in time with a theorical probability of surviving.
For example, I have a cohort of patients with cancer ...
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Am I using the chi-squared test correctly?
I have a set of $2,142$ measurements of some value that are grouped into $18$ bins of equal length (according to the value measured). I want to check the resulting distribution for uniformity.
As far ...
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Grubbs test: two/one-sided'nes and degrees of freedom
There are two things which confuse me about the Grubbs-test:
(1) The first aspect involves the two or one-sidednes of the test:
Lets assume I want to check if my W6 dice, where I expect the ...
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Chi square test of good fitting
I am trying to find the best way to fit my data, it looks like a modified sigmoid (code below). The problem I have is that my critical chisquare value is very high, am I then correctly calculating the ...
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Pearson chi-squared vs. logistic regression?
I have a dataset with calf serum BHB concentration expressed as low (<150) or high (>150). I want to know if there is a difference in BHB between age categories (weeks). I tested two analysis:
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Hypothesis Testing via Chi Squared
I am having trouble understanding the application of chi square "power of the test" in context to hypothesis testing. The following is not homework, I'm simply providing an example to convey ...
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How to generate significant level for the following data (Fisher exact)
I have a categorical data that I don't know how to generate the significant level.
Row = Group A and Group B;
Column = Unchanged, upgrade, downgrade (From left to right)
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I tried to run ...
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Why doesn't the G-test's Chi-squared "threshold" scale with sample size?
In the popular likelihood ratio test of goodness-of-fit (also known as the G-test: see, e.g., here), the test statistic is calculated as
$$G(\mathbf{O},\mathbf{E})=2\sum_{i=1}^{M}O_{i}\log\frac{O_{i}}{...
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Keep or remove insignificant covariance values when modifying CFA model?
I am working to improve goodness of fit in a CFA model and am wondering about if I should retain added covariance values that are insignificant. I am adding covariances that are indicated by ...
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How to compare seasonality between time series?
I have data like this:
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
x
0.03
-0.07
-0.62
0.26
0.47
0.01
0.54
0.41
-0.38
0.50
-0.84
-0.30
nx
0.23
0.45
1.12
0.45
0.53
0.95
0.56
-0.79
-1.68
-0.12
-0....
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