Tables of counts (occasionally proportions of marginal counts), arranged by (at least) two marginal categories, displaying bivariate or multivariate frequencies. Sometimes called crosstabs.

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Finding the differences for nominal data when each participant contributes to more than one cell in the frequency table?

Finding the differences for nominal data when each participant contributes to more than one cell in the frequency table. The point is that I don't have paired nominal data as it is in repeated ...
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enumerating patterns in a set of contingency tables

I have a set of 3X3 contingency tables and want to identify the distribution of the patterns by comparing their expected and observed number of samples in each cell using a right statistical test. For ...
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37 views

Cramer's $\phi $ for three-way contingency tables

Can Cramer's $\phi $ be determined for three-way contingency tables? I know how to calculate the expected values, chi squared, and how Cramer's $\phi $ works with two-way contingency tables. However, ...
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Which exact test should I use for my data?

I'm very new to statistical analysis, and I am wondering if I am paying too much attention to unimportant questions. My data consists of about 40 cases involving a particular kind of lawsuit. After ...
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2answers
50 views

$\chi^2 $ of multidimensional data

I want to test if two observations of nominal data accord to the same distribution. I am using the chi squared statistics to perform a chi squared homogeneity test and normalize the result with ...
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1answer
54 views

How to interpret the residual colors on a mosaic plot?

This is a mosaic plot of contingency table dataset HairEyeColor described here. How do I interpret the colors representing residuals? What is the difference ...
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Which is the best visualization for contingency tables?

Which is best plot, from statistical standpoint, to show a contingency table, which is typically being analyzed by chi-square test? Is it a dodged barplot, stacked barplot, heatmap, contour plot, ...
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171 views

Fisher exact test on paired data

Given $40$ cases with lung cancer and $40$ matched controls (without lung cancer) (matching based on age, sex, etc.). To try to find evidence between the effect of smoking on lung cancer, I used ...
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44 views

Determining $\chi^2 $ for Cramer's $\phi $

I intend to determine Cramer's $\phi$ for two contingency tables of the following form: ...
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1answer
80 views

I don't understand Chi squared

I think of the contingency table test. In all textbooks I've seen, the test statistic is calculated as the sum of $(O-E)^2/E$ over all cells. But the degree of freedom is not the number of all cells. ...
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How important is the arrangement of data in a 2x2 contingency table for fishers exact test?

I am comparing expression of different genes involved in the same metabolic reaction of basil to two different conditions, exposure to cold Vs Infra-red light. I am in the process of analysing RNA seq ...
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1answer
34 views

Is it possible to compute the mean/median of an variable by a contingency table?

A contingency table contains the frequencies of two discretized variables. To be more specific, the discretization is done by splitting the spectrum of a signal into equal width intervals. Is it then ...
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1answer
48 views

Using contingency tables for testing multiple dependencies

I know that I can determine the correlation / association / dependency between two variables (X= smoker, and Y=cancer) using chi-squared with a 2x2 contingency table: ...
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1answer
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Help with analyzing/planning a physical experiment — regression

This is a real experiment about to be performed Batches of samples will be prepared. A Striker will be used to see if a reaction will occur. For example: 20 drops might be performed, and number of ...
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Test for independence in 3x2x2 table with small expected cell values

I have three unordered categorical variables. I have made a 3x2x2 table, but I'm uncertain of how to test for independence. The usual manner is a chi-squared statistic, but I think this is ...
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rxc contingency tables

Hi I am trying to analyse categorical data and to construct a contingency table based on a survey data. In the contingency table, there were 5 ordinal ratings(blank, unacceptable, below average, ...
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249 views

Why does Pearson's chi-squared test detect differences that the GLM model fails to detect?

How can I interpret the following result? I have 4 groups with around 300 observations each: ...
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44 views

Disproportioned contingency table

I have a database of clients, some of which have gotten a special pill - and the rest have not gotten the special pill. Afterwards I measure if the clients starts exercising. My contingency table ...
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1answer
57 views

Contingency table for gene groups

I have two lists of genes as follows: DEList has 282 gene names AllList has 32805 gene names ...
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32 views

A generalized measure of relative enrichment for elements of a contingency table [closed]

Problem: If given a matrix of counts of observations between some features (F) f1-f4 (e.g., GO terms or pathways, in rows) and genes / proteins (P) p1-p3 (in columns), what would be: A good way to ...
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Help interpreting this result based on conditioning on gender -Contigency Tables

The problem i'm having is how to interpret the results I got. For part a) I got that the abortion laws are independent of generation where I used a $\chi^2$ test. For part b) I got that the the age ...
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Regression Model for Matched Continency Tables Coefficient Interpretation

Sorry to insist. A number of questions in the same direction (coefficient interpretation) by different contributors, never answered. ...
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1answer
30 views

Regression Model for Binary Matched or Paired Contingency Table Results

This is a follow-up question on a prior thread about the same setup as follows: We have two "Methods" ("A" and "B") to diagnose a medical condition. We are not trying to determine which one is better ...
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Fisher's exact test for 3x5 contingency table in R with post-hoc? Consistently with using Fisher or Chi-squared?

I'm struggling with some (relatively simple) stats questions for some work I'm doing in R, and can't seem to find answers online... I have a factorial response variable of habitat type of a species ...
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Correlated Proportions shown in a Mosaic Plot. What is the fitted model that generates residuals?

I have a 2-by-2 table of correlated proportions where I am plotting the positivity of two diagnostic methods applied on a sample of 216 individuals: ...
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Dimension reduction for discrete qualitative and aggregated variables

I know about PCA for multiple dimensions of continuous features but here is a problem I have some trouble to find a method for. I don't have a list of individual countries but rather a discrete ...
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32 views

Fisher's Exact Test for 2x3 tables

I'm writing my dissertation and I need to cite a source to support using the FET for 2x3 tables. Does anyone knows of a source that can be cited? Thank you!
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1answer
36 views

Is this a valid use of “positive predictive value”?

So here's your typical table for evaluating the performance of a diagnostic test: Gold standard result ...
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Calculating Odds Ratios for a 3 x 3 Table

How would I go about calculating the Odds Ratios (measures of association) for a 3 x 3 Table
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147 views

Is the chi-squared test appropriate with many small counts in a 5x2 table?

I have two sample populations, A, and B, which are independent. ...
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112 views

SPSS chi-square output interpretation

Sorry for the dumb question, I need some help with the interpretation of the spss chi-square test outcome. Basically I have two variables: the first one is a binary variable which takes value 1 if a ...
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2answers
171 views

How to simulate effectiveness of treatment in R?

Let's say I want to write a simulation for the table below to decide if Xylitol treatment and ear infections are independent. How would I go about doing this?
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1answer
41 views

chi-squared / Fisher's exact test with incomplete data for contingency table

I have a treatment group (n=42) and a control group (N=12). From this this, 13 used in the treatment HTN drugs and 4 people in control group used HTN drugs. How should the contingency table be set ...
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35 views

Test of Independence Between Two Nominal Variables With Many Levels Each

I am looking to test whether there is a significant relationship between two nominal variables, one which has 100 levels and the other with 10 levels. I initially considered doing a $\chi^2$ test of ...
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1answer
172 views

Computing the power of Fisher's exact test in R

Suppose that I have the following 3 x 3 contingency table: ...
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32 views

A question about the distribution of the log odds ratios in multivariate contingency tables

I know that in $2 \times 2$ tables, one may compute the standard error of the log odds ratio by the formula $$\sqrt{\frac{1}{N_{11}} +\frac{1}{N_{12}}+\frac{1}{N_{21}} +\frac{1}{N_{22}}}$$ where the ...
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1answer
603 views

how to compare two percentages to prove for statistical significance

I have problem to compare the two percentages and to get the statistical significance for these two different percentage. I just want to approve whether these two percentages are significant or not ...
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382 views

What distribution does Fisher's exact test assume?

In my work I have seen several uses of Fisher's exact test, and I was wondering how well it fits my data. Looking at several sources I understood how to calculate the statistic, but never saw a clear ...
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1answer
52 views

Denominator term in Chi-Square-Test for association in a contingency table

The general formula for the Chi Square Test for association in a contingency table with $I$ rows and $J$ columns, and cell counts $n_{ij}$ is $$ \chi^2 = \sum_{i=1}^I \sum_{j=1}^J \frac{(n_{ij} - ...
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chi-squared test vs fisher's test vs … => highly unbalanced length frequency data

I would like to statistically verify if two distributions are identical. Basically, the first distribution is a length frequency distribution from a large population ("population"). The second is the ...
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2answers
101 views

Chisquared on categorical data or a Wilcoxon test on the counts hereof?

This question is related to a question I had in R on SO here The background of my question is fairly simple. I was given two "databases" in the form of data.frames ...
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1answer
51 views

How to perform a conditional cross-tab in R or Excel? [closed]

I recently was given a project which consists of: pulling together words from ~500 small tweets and doing a matrix, which shows which words occur together in which tweets. I am wondering how I can ...
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92 views

Hypothesis testing using R

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1answer
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Log Linear Models: Interpretation when None Fit

This is question 9.6 from Categorical Data Analysis by Alan Agresti (Wiley, 2013). The question asks us to find a Log Linear with the best fit for a 2x2x2 contingency table. The following are the ...
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How to adjust logistic models in case bivariate analyses encounter issues?

The model looks like: Y = X1 + X2 + ... + Xi Y is categorical or, to be exact, ordinal Xs can be categorical (dichotomous, ordinal, nominal) or continuous I first run bivariate analyses between Y ...
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Does N-1 correction for Pearson's Chi-Square apply to r x c tables generally?

Campbell (2007) recommended what he called the "N-1" correction for chi-square tests performed on two-by-two contingency tables. He described the correction as: "the K. Pearson chi-squared test ...
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54 views

How to enter data into contingency table directly?

I'd like to create a contingency table. I do it using: matr=matrix(c(62,61,36,19,10,21,58,60,39,22,12,19,91,83,72,23,52,62,43,28,59,57,29,20,12),5,5) but it ...
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1answer
151 views

Hypothesis testing based on Likert type data

I know this site is full of similar questions, but either their answers do not apply, or I'm missing something. I have data from a questionnaire. Responses are in the form of Likert items, some of ...
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51 views

Seeking basic advice re. contingency matrix for time-limited predictions

I am looking for advice on how to construct a contingency matrix ... A subject is measured on day 1 and a score is computed. This is repeated daily generating a series of scores. If on a given day ...