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    how to save MLR output?

    Hi, How can one save the outputs for 1. step-wise regression (steps, summary and anova) 2. summary (lm) 3. anova(lm) into text or word files without disturbing the table structures? Also, how to code this for auto-saving if there are large number of regressions to be performed and the...
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    Confused: Mixed model, step-wise regression, testing for random effects

    Dear all, I want to perform a MLR (mixed model) on a data set (details below) that has both numeric and categorical explanatory variables. The data is as below: Sample number: 85 Response variable: Y (numeric) Explanatory variables: Sr.No. Variable...
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    Can the PCA scores be used as variables in multiple linear regression

    Hello, I used PCA to reduce the dimensions of a data set of 10 variables into 2 principal components (describing 82% of variance in data set of 10 variables) and calculated the scores for both PCs for all the samples (n=85). Can I use these PCs (Scores) (separately or together) as...
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    Using principle component as explanatory variable in multiple regression

    Hello, I used PCA to reduce the dimensions of a data set of 10 variables into 2 principal components (describing 82% of variance in data set of 10 variables) and calculated the scores for both PCs for all the samples (n=85). Can I use these PCs (Scores) (separately or together) as...
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    Multiple Linear Regression Problem

    Hi, I want to do a multiple regression analysis. I have one Y which are numeric values (sample number = 85) and the following Xs. Sr No Variable Data type Data example 1 Region 4 factor levels Region ABC 2 Class 3 factor levels...
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    cooks distance cutoff

    Hello, I urgently need to find out what is happening in regards to below: I am doing a huge number of simple linear regressions. For each regression I want to use outlier test (outlierTest(fit)) and influence index test and influence plots to identify outliers and influential data points. I...
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    normality transformation and regression

    Hi, I have performed 1/sqrtY, and sqrtY transformations on different data sets to achieve normal distribution for simple linear regressions. So after performing these regressions, please advice if the following is correct. In following, X is independent variable and Y is dependent...
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    using multiple arguments (for executions, not conditions) for 'if' function

    Hi, Within a nested for loop, I am trying to do something like If (p<0.05), then (do A, and do B and do C), else (do nothing) To give details if (p<0.05 ) {jpeg(file = paste("Bbl", ".jpeg", sep="")) IP<-influencePlot(Reg) IP<-cbind(ID,IP)...
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    Is multiple comparison correction analysis applicable? If yes, which one?

    Hello, I am doing simple linear regressions between a number of ecological variables and 10 different landform parameters. For each ecological variable, I am looking for which of the landform parameters show significant (o.05) relationships. As I am looking at 10 regression results (one...
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    'layout function'

    hello all, I am trying the layout function as I need to plot ten plots in 5 rows and 2 columns. I am trying the following command, but something is going wrong that I could not figure out. Can you please help me with this? layout(matrix(c(1,2,3,4,5,6,7,8,9,10),nrows=5, byrow=TRUE)...
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    Plotting in R

    Dear all, I am new to R and am trying to draw some plots in R. I am not able to figure out how to control the labels and marks(positions,number) of ticks ticks, and also how to restrict the length of trendline to the dataset. I also have a few other minor questions. Can someon eplease help me...