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    Fit a non-recatngular parabola in R

    Hello, I'd like to fit the formula below to a non-rectangular parabola in R. C = (XI+A-√((ϕI+A )^2-4XϕIA))/2X-R I have several data points that have values for both C and I. I have an estimate for X, A, ϕ, and R. So I'd like to use the estimates with each observation to get the fitted...
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    Reduce number of predictor variables ((multi)collinearity): PCA not helpful

    Howdy, The attached spreadsheet contains the correlation matrix of predictor variables and response variable. Correlation exists between them. Additionaly included are the results from a Principal Components Analysis on my (scaled) predictor variables. I used the prcomp command in R with the...
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    Appropriate regression for dependent count data and independent "not count data"

    Hello, My independent data are continuous variables. My dependent variable is count data. I want to use regression to look for a relationship. Generally speaking, what is/are appropriate regression(s) for this situation? Thank you kindly, Mike
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    Should I transform my response data (count data)? Impact on subsequent analyses?

    Hello, My response variables are derived from count data. I have the biennial winter population counts of a hibernating mammalian species (sites / n =226). My predictor variables are from two time steps (i.e. 1992 and 2001). I created my response variables from the following to correspond...
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    How to rank (overall) correlation of variables within a correlation matrix

    Hello, I have six correlation matrices in an Excel spreadsheet. Each has the same variables but reports on a different group. I would like to rank the variables across all groups from least correlated to most correlated. There are 8 variables: ENNMN.r CONTAG.r LSI.r ED.r PAFRAC.r...
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    How to use a Distance Matrix as an Independent Variable?

    Hello, Let's say I have 100 locations. I know the distance between each location (i.e. distance matrix). How can I use the distance matrix (or some derivative) as an independent variable to access significance (if any) with the dependent/response variable(s)? Any ideas? Thanks,