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.
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Difference in output between SAS's proc genmod and R's glm
I'm trying to replicate a model fitted in SAS in R but the fit I'm getting gives me slightly different coefficients and standard errors.
Data:
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R vs SAS, why is SAS preferred by private companies?
I learned R but it seems that companies are much more interested in SAS experience. What are the advantages of SAS over R?
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Conflicting results of Type III sum of squares in ANOVA in SAS and R
I'm analyzing data from an unbalanced factorial experiment both with SAS and R. Both SAS and ...
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2
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Formula for autocorrelation in R vs. Excel
I am trying to figure out how R computes lag-k autocorrelation (apparently, it is the same formula used by Minitab and SAS), so that I can compare it to using Excel's CORREL function applied to the ...
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2
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Beyond AR(1) as a covariance structure for mixed models with repeated measures
I have been reading about alternatives to assuming an AR(1) covariance structure for mixed models with repeated measures (in time). In particular I have heard about Toeplitz and Ante-dependence ...
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Which is the best method for network meta-analysis?
There are now several different approaches to perform a network meta-analysis or mixed treatment comparison.
The most commonly used and accessible ones are probably the following:
in a Bayesian ...
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What exactly is the Box-Jenkins method for ARIMA processes?
The Wikipedia page says that Box-Jenkins is a method of fitting an ARIMA model to a time series. Now, if I want to fit an ARIMA model to a time series, I will open up SAS, call ...
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1
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Differences between PROC Mixed and lme / lmer in R - degrees of freedom
Note : this question is a repost, as my previous question had to be deleted for legal reasons.
While comparing PROC MIXED from SAS with the function lme from the <...
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Can I use a variable which has a non-linear relationship to the dependent variable in logistic regression?
Let's say I am building a logistic regression model where the dependent variable is binary and can take the values $0$ or $1$. Let the independent variables be $x_1, x_2, ..., x_m$ - there are $m$ ...
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Non-parametric for two-way ANOVA (3x3)
My dependent variable is continuous, non-normal (skewed left according to Shapiro-Wilk test). I have two independent variables (treatment group by colour, food type). There are 3 levels within each ...
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2
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Why does SAS PROC GLIMMIX give me VERY different random slopes than glmer (lme4) for a binomial glmm
I am a user more familiar with R, and have been trying to estimate random slopes (selection coefficients) for about 35 individuals over 5 years for four habitat variables. The response variable is ...
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3
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Using computer simulations to better understand statistical concepts at the graduate level
Hi I'm taking a graduate course in Statistics and we've been covering Test statistics, and other concepts.
However, I am often able to apply the formulas and develop a sort-of intuition on how stuff ...
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11
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1
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Convert SAS NLMIXED code for zero-inflated gamma regression to R
I'm trying to run a zero-inflated regression for a continuous response variable in R. I'm aware of a gamlss implementation, but I'd really like to try out this algorithm by Dale McLerran that is ...
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1
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Equivalent mixed models yielding different results in SAS
Below I show two equivalent ways to write a mixed model in R and SAS. The two R models as well as the two SAS models yield the same estimates of the random and fixed effects and the same standard ...
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