# correspondence-analysis's questions - English 1answer

85 correspondence-analysis questions.

### PCA on a heterogenous correlation matrix better than MCA?

I have a questionnaire of 80 questions that I need to do dimension reduction on. About half the questions are ordinal (Likert-style questions), and the other half are qualitative/nominal. I've been ...

### Application of Factor Analysis to a table of count data

I am being asked to apply a statistical technique that I do not think is optimal. I have asked before, but was told my question was vague. I have re-worded it appropriately here. I am being asked to ...

### 3 Assumptions for Canonical Correspondence analysis

I have been trying to find the major assumptions a Canonical Correspondence Analysis makes when doing its analysis. I have had a hard time finding anything useful. I did, however, find the assumptions ...

### 1 Detrended Correspondence Analysis - site ordination with species vectors

I have performed a Detrended Correspondence Analysis for species composition of different replicate survey sites and constructed a site ordination plot. Sites were classified into habitat types, so I ...

### 2 Is MCA equivalent to PCA when all variables are binary?

I am looking to apply principal component analysis on binary (true/false) data, and I have come across the "equivalence between PCA and MCA" (Multiple Correspondense Analysis) for binary data, but ...

### MCA and K-Means simultaneously

I was reading the article Multiple Correspondence K-means: Simultaneous versus sequential approach for dimension reduction https://link.springer.com/chapter/10.1007/978-3-319-55477-8_8 I have this ...

### 120 Can principal component analysis be applied to datasets containing a mix of continuous and categorical variables?

I have a dataset that has both continuous and categorical data. I am analyzing by using PCA and am wondering if it is fine to include the categorical variables as a part of the analysis. My ...

### 1 Canonical Correspondence Analysis: how to interpret results

0 answers, 27 views ecology correspondence-analysis
I am using Canonical Correspondence Analysis (CCA) to analyze phytolith abundances (similar to pollen) over environmental gradients. As I am new to CCA, I read some background info. The following ...

### How to view the predicted unimodal response of a Canonical Correspondence Analysis?

I'm trying to understand the predicted patterns of a Canonical Correspondence Analysis (CCA). I understand one of this method's strengths in understanding ecological patterns lies in its assumption of ...

### 6 Difference between canonical correpondence analysis and canonical correlation analysis

I am bit confused between two terms Canonical Correpondence Analysis and Canonical Correlation Analysis. Are the two some how related or they are entirely different techniques? Do they point to ...

### PCA, CA, MCA results as variables

Good day. There are two questions to the community. Can PCA / CA results be described by means of average, standard deviations, medians, etc.? How to use them in regression models and typical ...

### 18 What is the “horseshoe effect” and/or the “arch effect” in PCA / correspondence analysis?

1 answers, 5.116 views pca eda ecology correspondence-analysis
There are many techniques in ecological statistics for exploratory data analysis of multidimensional data. These are called 'ordination' techniques. Many are the same or closely related to common ...

### 1 I have done crosstabs and a Correspondence Analysis, having trouble reporting and interpreting Chi-Squared and Inertia?

0 answers, 21 views chi-squared correspondence-analysis
I have data on 1500 cases with two variables (color, genus) with 5 colors and 6 genera. I almost had generally equal spread across genus, but one is disproportionately represented and has about twice ...

### 8 Discrete data & alternatives to PCA

I have a dataset of discrete (ordinal, meristic, and nominal) variables describing morphological wing characters on several closely related species of insects. What I'm looking to do is conduct some ...

### 2 Is Multiple Correspondence Analysis applicable to Multi-valued Categorical Variables?

I have a data-set containing only Categorical Variables. I needed to do Principal Component Analysis on the data set. Eventually, I found Multiple Correspondence Analysis and learnt it. But, in MCA, ...

### 1 How to analyse multiple choice and overlapping questions in MCA?

I need to analyze a survey about entrepreneurship which has around 50 categorical variables. Therefore, after some univariate analysis, I want to apply Multiple Correspondence Analysis (MCA) in order ...

### 5 Is there a specific name for this plot?

This plot represents the popularity of technologies in two "tools", vue and react. In left-top corner are specific technologies for vue but not for react, right-top technologies popular in both tools ...

### Co-Correspondence Analysis (CoCA) Result Interpretation

I'm trying to interpret the results of Co-correspondence analysis (CoCA) with the R package cocorresp. The descriptive paper is rather unclear about how to interpret the results. I've performed the ...

### MCA explaining only 10% of the data

0 answers, 29 views r correspondence-analysis
I want to find relevant variables to do a market segmentation. I have run an MCA with 10 variables on R. Among them : 1 is a supplementary qualitative variable (whether our customer has churned or ...

### 1 How to interpret the results of my correspondence analysis?

0 answers, 242 views r correspondence-analysis
Im looking for help interpreting an CA Factor MAP my df is : ...

### Can i treat Asselin 2002 linear categorical composite indicator of multiple correspondence analysis as a geometrical function as in OECD 2008?

in Asselin (2002) http://www.ipc-undp.org/conference/md-poverty/papers/Louis-Marie_.pdf , the expression of the categorical composite indicator of multiple correspondence analysis (qualitative ...

### How to get weights to develop an Index using Multiple Correspondence Analysis (MCA)?

I have set of dichotomous variables and I am using Multiple Correspondence Analysis to develop an Index out of these variables. I have earlier tried Principal Component Analysis (PCA), but then ...

### Canonical Correspondence Analysis vs Principal Component Analysis - Marine ecology XCELSTAT Beginner

I want to analyse how the presence of reef fish species relates to benthic habitat cover at numerous survey sites (reef fish are measured via simple abundance counts and habitat cover is measured in ...

### Multi Correspondance Analysis as a simple CA

I've been dealing with a dataset full of categorical variables and had some issues to apply dimensionality reduction techniques as PCA is no great fit for such datasets. After some research, I came ...

### 3 Displaying large number of text labels on a scatter plot

Having too many species in the data, makes the species labels overlap in a plot of a canonical correspondence analysis. This makes it difficult to interpret. Is there a reasonable possible solution? ...

### 2 What in cross validation from co-correspondence analysis indicates sufficient axes numbers?

The coca function at cocorresp package disponible for R provides a predictive way to relate two biological composition datasets. I need help to understand one step from examples on documentation ...

### 2 No departure from independence term in constrained correspondence analysis

0 answers, 47 views count-data correspondence-analysis
I am used to think of correspondence analysis (CA) as dissecting the weighted departure from independence through singular value decomposition, but I cannot relate this to constrained correspondence ...

1 answers, 75 views correspondence-analysis biplot
I am trying to do a Canonical correspondence analysis (CCA) using the community data and chemical data. I have my family level taxonomic data as community data. In chemical data I have 18 variables: ...

### 2 Interpreting Canonical Correspondence Analysis (CCA) Inertia - in Vegan

I am wanting to know if I can use the ratio of Constrained/Total Inertia in my CCA to describe 'The variability explained by my constraining variables'. I am asking because I've seen different ...

### 1 Should PERMANOVA be used to select factors for Canonical Correspondence Analysis?

I am interested in investigating the relationship between species composition and several environmental factors. My question is whether it is appropriate to use PERMANOVA to select a 'best' ...

### 1 Applying Multiple Correspondence Analysis when predictors have thousands of levels

I apologize in advance if my english isn't too clear. Please feel free to leave a comment and tell me what part doesn't make sense. I'm currently working on a dataset which contains web data and I ...

### 4 How best to normalize count data to compare two distributions

Say I have a vector of length 1000. At each position (1 ... 1000) there is a count. I have two vectors with different range of counts such that in vector A the maximum number of counts at a position ...

### 2 CCA species coordinates relative to ordination surface

I want to display species coordinates relative to an environmental variable using ordination surface (ordisurf in vegan package)...

### 3 Mathematical formulation of correspondence analysis?

From a website you can think that Correspondence Analysis is a categorical data version of PCA. But the main usage of Correspondence Analysis is different from that of PCA, and it is more like ...

### Multiple correspondence analysis with fuzzy coding

1 answers, 281 views correspondence-analysis fuzzy
I have a data set with six continuous variables. I would like to perform a multiple correspondence analysis (MCA) with fuzzy coding. I was able to create the fuzzy coding, so for each original ...

### 2 Calculate similarity between assortment of grocery shopping basket

I am trying to measure distances between basket assortments in a grocery shopping. I have all information that who buys what in every shopping by online and offline. I want to see the pattern of the ...

### 1 Is there an analog to logit Y-aware PCA for correspondence analysis?

I came across this tutorial of logit Y-aware PCA for dichotomous \$Y\$s. Does anyone know if there is an analogous procedure for correspondence analysis? It seems that there couldn't be since the Y-...

### How do I interpret a plot of variables created in FactoMineR?

1 answers, 567 views r pca correspondence-analysis
I'm using the FactoMineR package in R to do a Multiple Correspondence Analysis on a large set of data. Specifically, I'm looking for correlations among a set of five categorical variables. I used the ...

0 answers, 332 views r pca correspondence-analysis biplot
I'm running a multiple correspondence analysis in R using the FactoMineR package: ...

### 1 Map using correspondence analysis

I was studying by my own correspondence analysis and I got some questions about the map that one gets using this method for some rows and columns. For example the following map: http://www.statmethods....

### 1 Regarding correspondence analysis

Can we use percentage values obtained from secondary source instead of frequency values in the contingency table for using the correspondence analysis? eg: in a contigency table with row variable ...

### 1 Correspondence analysis vs chi square

0 answers, 206 views r chi-squared correspondence-analysis
My data: ...

### 1 Do I need to standardize environmental data before canonical correspondence analysis?

I have a dataset of 15 environmental variables (soil physical and chemical properties) and about 25 "species" variables for about 40 sampling sites. I want to do a CCA to analyse the effects of the ...

### 2 How to test for the effects of plant community composition on insect community composition whilst controlling for geographic distance?

I'm trying to test for the effects of plant community composition on insect community composition using ordination, but I need to control for geographic distance. I know CCA can handle three matrices ...

### 1 Minimize shared variance of columns between factors in Correspondence Analysis

I am using correspondence analysis (CA) to analyze a contingency table. In the columns I have statements about some brands (characteristics) and in the rows I have the brands. My aim is to obtain in ...

### 35 PCA and Correspondence analysis in their relation to Biplot

Biplot is often used to display results of principal component analysis (and of related techniques). It is a dual or overlay scatterplot showing component loadings and component scores simultaneously. ...

### 1 I want to run a same result of biplot in R

There is a software called Brandmap\$^1\$ which can return a biplot from a matrix. I am trying to run the same result in R but the coordinates are not the same. First I input a simple matrix into the ...

### 2 It is possible to apply correspondence analysis to a 2x2 contigency table?

I was wondering if it is possible to apply correspondence analysis to a 2x2 contingency table. Since that correspondence analysis is a method for dimensionality reduction, I think it is necessary to ...

### 1 Visualizing a correspondence analysis over time

I have two contingency tables of frequency data examining the same set of variables but at two different time points. I can make two separate before and after correspondence analysis plots but would ...

### 19 Interpreting 2D correspondence analysis plots

I've been searching the internet far and wide... I have yet to find a really good overview of how to interpret 2D correspondence analysis plots. Could someone offer some advice on interpreting the ...