Questions tagged [biplot]

Biplot or dual plot is an exploratory graph to present - as points or vectors - both the observations (sample) and the variables of the data. The axes are typically latent principal dimensions. Biplot is often used to depict principal component analysis, correspondence analysis, and other multivariate methods.

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37
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1answer
12k views

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. ...
17
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1answer
14k views

What is the proper association measure of a variable with a PCA component (on a biplot / loading plot)?

I am using FactoMineR to reduce my data set of measurements to the latent variables. The variable map above is clear for me to interpret, but I am confused when ...
18
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1answer
9k views

Positioning the arrows on a PCA biplot

I am looking to implement a biplot for principal component analysis (PCA) in JavaScript. My question is, how do I determine the coordinates of the arrows from the $U,V,D$ output of the singular vector ...
9
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3answers
19k views

Can the scaling values in a linear discriminant analysis (LDA) be used to plot explanatory variables on the linear discriminants?

Using a biplot of values obtained through principal component analysis, it is possible to explore the explanatory variables that make up each principle component. Is this also possible with Linear ...
9
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1answer
4k views

Data space, variable space, observation space, model space (e.g. in linear regression)

Suppose we have the data matrix $\mathbf{X}$, which is $n$-by-$p$, and the label vector $Y$, which is $n$-by-one. Here, each row of the matrix is an observation, and each column corresponds to a ...
31
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3answers
11k views

Visualizing a million, PCA edition

Is it possible to visualize the output of Principal Component Analysis in ways that give more insight than just summary tables? Is it possible to do it when the number of observations is large, say ~...
30
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2answers
77k views

Interpretation of biplots in principal components analysis

I came across this nice tutorial: A Handbook of Statistical Analyses Using R. Chapter 13. Principal Component Analysis: The Olympic Heptathlon on how to do PCA in R language. I don't understand the ...
19
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1answer
15k views

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 ...
18
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2answers
13k views

What are the four axes on PCA biplot?

When you construct a biplot for a PCA analysis, you have principal component PC1 scores on the x-axis and PC2 scores on the y-axis. But what are the other two axes to the right and the top of the ...
10
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1answer
8k views

Arrows of underlying variables in PCA biplot in R

At the risk of making the question software-specific, and with the excuse of its ubiquity and idiosyncrasies, I want to ask about the function biplot() in R, and, ...
4
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1answer
6k views

What are the units in this PCA biplot? [duplicate]

This is a plot of my data These are the values: ...
7
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1answer
1k views

Variable ordering using PCA

I've downloaded a script to draw a correlation matrix using colored circles. This script allows to order variables using PCA, but I'm not sure how it works. The code responsible for ordering is below: ...
11
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1answer
21k views

What is the difference between “loadings” and “correlation loadings” in PCA and PLS?

One common thing to do when doing Principal Component Analysis (PCA) is to plot two loadings against each other to investigate the relationships between the variables. In the paper accompanying the ...
6
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1answer
1k views

Interpreting 2D correspondence analysis plots (Part II)

I'd like to ensure that I understand the process correctly. This is a follow-up question to Interpreting 2D correspondence analysis plots ...
2
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1answer
14k views

How to interpret this PCA biplot?

I am approaching PCA analysis for the first time, and have difficulties on interpreting the results. This is my biplot (produced by Matlab's functions pca and ...
3
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1answer
6k views

Interpretation of PCA biplot?

I just ran my first ever PCA, so please excuse any naivety on my part. As input, I used five years worth of the following: S&P/ASX 200 A-REIT S&P/ASX 200 Consumer Discretionary S&P/ASX ...
5
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1answer
873 views

Interpreting overlapping arrows on a PCA biplot: does it mean that the variables are redundant?

I'm new in principal component analysis (PCA) and I don't really understand the biplot representation of its results, so I would really appreciate some guidance. Having the example of the illustration ...
3
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1answer
80 views

How to analyze this biplot of PCA?

I have dones a PCA analysis about measurement of a fish morphometric between female and male. After the PCA result came out with biplot graph, I was a little bit confused to interpret this data. It ...
5
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0answers
2k views

Interpretation of biplot in PCA

Blue points all appear in the lower right-hand quadrant in the plane formed by the first two principal components. Is it a good interpretation of the biplot (right panel) to say that blue points are ...
2
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1answer
812 views

Linear Discriminant Analysis biplot [closed]

I am not sure about plotting a biplot for LDA. Suppose I have a 3 feature data set with 3 classes. Then, I perform LDA to reduce the dimensionality to 2. How can I create a biplot for the LDA? My ...
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0answers
888 views

Angles between variables on a PCA biplot and correlations between the variables

A friend or mine has performed a PCA and he asked me for help about interpretating a biplot. In that biplot I found that the vector representing a variable, say A, forms a very wide angle, perhaps ...