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    Mixed model Beta distribution fit diagnostics

    Hello, I have a split-plot design and I want to test the effect of 2 factors on the disease incidence (continuous proportion). I am using Beta dist. which is appropriate for these data (bounded within 0-1). The fit statistics look OK (Pearson Chi-square/DF close to 1) Fit Statistics for...
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    proc fastclus output interpretation

    Hello, I am using proc fastclus to perform k-means clustering. In Figure 42.2: Cluster Summary Table from the FASTCLUS Procedure, an R-square value is reported (please see link below)...
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    Mixed model LSMEANS vs ESTIMATE (BLUP)

    Hello, I am analyzing data from a multi-location trial (5 locations) to test the effectiveness of a treatment with 2 levels. The design is RCB with 3-4 replications in every location. I use the model below: proc mixed data=mydata; class location rep trt ; model Y=trt/ddfm=kr2 residual...
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    multi-location latin square design analysis

    Hello, I have a 5 x 5 Latin square design which is replicated 5 times within each location (same rows and columns in each location). The same design was used in 10 different locations and I was asked to perform a combined location analysis. I have done it before with other designs, such as RCB...
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    meta-analysis vs. random effect combined analysis

    I have data from 200 similar studies, all measuring the same effect of a continuous independent variable on the same continuous response. I say similar because the designs are different (split plot vs. rcbd) and the levels of the independent variable is not the same across all studies. I have...
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    permutations "partykit"

    Hello, I am new to R and I was reading about conditional decision trees. In the "party" package there is an option to select number of permutations (nresample=...). However, that is not the case with "partykit". So does it use permutations, even if it is a constant number and I can't...
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    split-split plot with continuous subplot variable

    Hello I am trying to analyze data from a split-split-plot design. The sub-plot is a continuous factor and since we suspect a non-linear relationship, the quadratic form needs to be tested as well. Factors: a-main plot-5 levels b-subplot-continuous c-sub-subplot-2 levels. To test the quadratic...
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    specify correct random effects

    Hi all, I have a CRD with 4 reps and 4 treatments (A, B, C, D). The study took place in 1 location for 3 years. I want to pool over years (so treat year as random effect). I am interested in main effects and up to 2-way interactions. So I am using the following model and random statement...
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    parameter estimate of categorical variable

    I run multiple regression with 2 continuous and 1 categorical variable (3 levels). SAS will hold the last level of the categorical variable and will not give an estimate. I know that this is the intercept. My question is how to calculate the interaction of the continuous variable with the 3rd...
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    non-mutually exclusive outcomes

    Hi, I have 4 outcomes (A B C D) that one of them is calculated as a weighted average of the first 2 (D=0.6*B + 0.4*C). Then I ran ANOVA to examine the effect of 2 factors on the 4 outcomes. My analysis was rejected because they said that D is not mutually exclusive from all other factors...
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    Spatial Statistics and SAS Books

    Hi all, I am looking for a book that explains applied Spatial Statistics methodology using SAS. I am interested in Spatial, Spatiotemporal data and Kriging. Thank you.
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    Time series regression books

    Hi, I am interested in Time series regression and I would like to find 1-2 good books that explain Time series with examples using SAS. Does anybody know and can propose good books that I can purchase? I am into agriculture/environmental science if that matters. Thanks
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    AMMI algorythm

    Hi, Does anyone has experience using AMMI (additive main effects and multiplicative interactions)? If yes, could you please provide practical information on how it works and SAS code that performs the analysis? This is a technique used in multi-location, multi-year plant breeding...
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    PCR interaction of PCs

    Hi, I am using PCA to avoid multicollinearity problems and then I want to use the first 2 PCs in linear regression. The 1st PC contains 60% of variability and the 2nd 32%. Is it valid if I use a data step in SAS, create a new variable which is the interaction of these 2 PCs and say that...
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    compare F statistics vs P-values

    Hi I have a question about comparing F statistics among effects. I have the following anova table Parameter Estimate Standard Error t Value Pr > |t| Factor1 12088.62915 2249.053598 5.37 <.0001 Factor2 -28.62915...
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    Passing-Bablok regression

    Hi all, Does anyone knows how to perform Passing-Bablok regression in SAS? I have never done it do the SAS code (with or withoutan example) would be very useful. Thank you!
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    Can I transform the principal components...?

    Hi all. I am using PCA to generate PCs and then using them as independent variables in regression. I added an extra data-step after PCA which is transformation of the PCs e.g. X=prin1^2 This significantly improved the subsequent regression model, however I am not sure if transforming the...
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    Three-way PCA

    Hi all, Does anybody have experience with 3-way PCA? Is there any example using SAS? I am not sure if I understand how it is different from the classical PCA... Thank you
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    overal test differ from lsmeans/pdiff results

    Hi all, I run proc mixed and I am not sure how to explain the following results... I am interested in starch content in 3 parts of the same plant (leaves, roots, husks). I am interested in the effect of one factor (3 levels) on starch content in the entire plant and individual parts...
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    Regression Model is not full rank

    Hi all, I am trying to detect relationship of crop yield at the end of the growing seasson (1 dependent variable) using amount of precipitation in May, June, July, May+June, June+july, Temperature in May etc. The problem is that I can't get p-values for many of these variables because of the...