Questions tagged [sas]
SAS is a statistical software package. Use this tag for any on-topic question that (a) involves SAS either as a critical part of the question or expected answer, & (b) is not just about how to use SAS.
230
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Degrees of Freedom using "Containment" method
I have a question about the way SAS uses the "containment" method to obtain degrees of freedom in mixed models. In particular, I think SAS does the wrong thing in obtaining df for least-squares means (...
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Specifying the linear predictor, survival function and PDF of a log-normal survival distribution
Continuing on my exploration of the log-normal distribution, I'm working on reimplementing some code originally written for a Weibull/Exponential model for a log-normal model. Among the things it does ...
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bias adjusted confidence interval for correlation coefficient
I stumbled across confidence intervals for $\rho$ in a statistics textbook. This was not part of the class, but I found it interesting. My textbook has a formula for this with a Fisher transformation, ...
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Mixed Anova in R
I am trying to do an anova anaysis in R. The experiment done had each subject tested in Method 1 and Method 2 as well a being in one of 4 different Levels (each subject in one group). The goal is to ...
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Reduced degrees of freedom using transformed data in one-way ANOVA (SAS PROC MIXED)
On pg. 88 of Design and Analysis of Experiments (8th Ed.) by Montgomery, he's analyzing square root transformed data in a one-way ANOVA. He provides an ANOVA table (SS, d.f., MS, F, p) for these data, ...
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What is the rationale behind the "eigenvalue > 1" criterion in factor analysis or PCA?
What is the meaning of "eigenvalue > 1" criterion? I understand what eigenvalues and eigenvectors are.
This question is w.r.t. this link and this statement there:
By default, VARCLUS stops ...
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Airline Fares - What analysis should be used to detect competitive price-setting behavior and price correlations?
I want to investigate price-setting behavior of airlines -- specifically how airlines react to competitors pricing.
As I would say my knowledge about more complex analysis is quite limited I've done ...
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GLMM with 2 insignificant variables has lower AIC or BIC compared to same model without those variables...?
Background
This post has been heavily edited from its previous version (three months ago).
I am investigating habitat selection of 35 territorial wolves over several years of denning seasons (41 ...
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Linear trend in SAS using contrast
I've been struggling with this problem for a couple of hours, and I could use some advice.
I have a linear regression model with two continuous predictors and a categorical one (with 4 levels). I ...
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Prediction model problem
I am trying to design a model that can estimate the number of customers I will receive in every store every month using the number of customers I received every month in every store for the last five ...
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What do I do if my predicted values are out of the dependent variable range?
I have built a beta regression model with log link for predicting adherence. My dependent variable's range is 0 to 1.When I used a test set to calculate the predicted values with the parameter ...
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Time Series: correcting the standard errors in a huge panel time series data set
I have stock returns at every 5 minute interval of each trading day for over 2 years for 40 stocks. I want to run a Fama-Macbeth regression by time interval (5min intervals) and then correct the ...
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How are Kenward & Roger's degrees of freedom computed in PROC MIXED?
I run the following SAS model:
...
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Interpretation of a log likelihood function for PROC NLMIXED in SAS
I have a data set of skewed nutrient intake values, from around 7800 individuals, of whom around 3000 had two measures of daily nutrient intake (the others only had one measure), so this is a repeated ...
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