compositional data and compositional data analysis, refers to varibles representing proportions, so non-negative and always summing up to one. See https://en.wikipedia.org/wiki/Compositional_data

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Problems with time series prediction

I got a question about modeling time series in R. my data consist of the following matrix: ...
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Overall $p$-value for a multiple linear regression (in MATLAB)?

I wish to explore the effects of the component percentages (independent variables) on fruit sweetness $S$ (dependent variable). Assume for simplicity that our fruit only contains 3 components, ...
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Dependent variable is proportion of population living in each census tract

I have data that contains - Dependent variable - proportion of the total population Independent variable - proportion of the total residential buildings and proportion of the total available land ...
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Mean in compositional data

I am required to analyse samples a compositional data set. However my samples come from seven different locations. Is there any way for me to check if there is a location/mean effect in the data which ...
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Proportions (compositions) in logistic regression

I have a logistic regression where some of the independent variables are proportions (compositions) that sum to 100 percents. Let's say that I have 4 such variables - I have ran the regressions 4 ...
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Understanding biplot for compositional data

Say in the biplot of some compositional data, I discovered that the links $\vec{AB}$ and $\vec{CD}$ intersect at roughly 90 degrees. So I can say that $\log {A\over B}$ and $\log{C\over D}$ are ...
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Multivariate data analyis of compositional data

Suppose I have a multivariate, compositional dataset that depicts the concentration of different elements. However, the data are not available on a single scale; i.e., some are of form 0.00x while ...
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Which variables should I transform, center, and/or standardize in my data for Principal Component Analysis?

I have multiple datasets that I am attempting to use principal component analysis (PCA) on in order to infer the underlying structure of the data. I'm attempting to predict growth increment of ...
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Finding mean and SD of 2 parts of a whole

I am putting together a review/meta-analysis of body composition in children. The data I will analyze consists of measures of fat-mass (FM) and fat-free-mass (FFM), which when summed equal total ...
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Analysing data measured as proportional composition

I have a data set on the proportional composition of marine substrate for different locations which I would like to compare. For example, one replicate transect within a location may be 50% sand, 25% ...
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Binomial GLM with unknown totals?

Essentially, I have some covariate data X, and a dependent variable Y consisting of proportions of a sample that shown a certain ...
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Multivariate proportional data

I am looking for literature on what I call multivariate proportional data where a single observation is a vector of proportions that sum to 1. For example, each person weights their preferences for ...