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.
686
questions
0
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1answer
23 views
When is it valid to use lasso and adaptive lasso
I am brand new to LASSO. I have a problem in that I have a data set without about 440 usable cases only about 42 of them of one level of the DV (every level of the DV and predictor have two levels). I ...
4
votes
2answers
174 views
Is it worth it to consider a MS Business Analytics program that is heavily focused on SAS? [closed]
I'm completing my undergrad this year and I've finished my graduate applications. I've been accepted to Oklahoma State University MS Business Analytics and Data Science. Looking through the ...
2
votes
1answer
40 views
How do I choose which confident interval for proportion difference to use in SAS?
In SAS, there are different CIs for proportion difference ($\pi_1-\pi_2$) to choose?
1.Continuity-corrected Wald CIs based on normal approximation
2.exact method
3.Miettinen-Nurminen CIs based on ...
5
votes
1answer
316 views
Has R fluency overtaken SAS in terms of being more popular as a hiring requirement? [closed]
Seems like when I first graduated (was a while ago, life went in a different direction and I wasn't an analyst for long), almost all the job listings wanted SAS? While R had only got limited traction ...
1
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1answer
38 views
How to analyze proportions data: Does the proportion of spent time in option A differ from the proportion of time spent in option B?
My research question is whether sheep prefer lying down on straw bedding (option A) or on a new type of bedding (option B). If sheep spent more time lying down on one option, we will say they have a ...
1
vote
1answer
32 views
glmer (R) versus SAS output random effects
I have a binomial glmm model which I have analysed in both SAS and R. However, I have noticed a difference in the statistics which are given for the random effect. In SAS, there is a table called '...
1
vote
1answer
19 views
Comparison between two groups of time series?
I have two groups of people. One group of people are healthy and the other group of people is sick. For people in both groups, I let them do exercise for 10 mins and then let them rest for 3 mins. I ...
2
votes
1answer
41 views
Reference books for mixed model
I am looking for reference to get a better understanding and overview of the mixed models. My goal is to understand the basic concepts and the formulas behind different models (I am having a hard time ...
0
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0answers
77 views
Multinominal conditional logistic regression
I have a dependant variable that comes with 3 categories A, B, and C, and I want to fit a multinominal logistic regression for an exposure variable, along with some confounding factors.
In order to ...
0
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0answers
14 views
Why would SAS proc mixed produce residual variance estimates under AR1 covariance structure, but none for unstructured covariance?
I am working on a program in SAS that seeks to extract r2 based on the residual variance produced by covariance parameter estimates in PROC MIXED.
The specification ...
1
vote
1answer
42 views
How to interpret this SAS poisson regression output?
I have a dependent variable being positive, discrete (number of people migrated) and the independent variables are all continuous. I want to study the impact of the independent variables on the ...
0
votes
1answer
35 views
What's the difference between Average Square Error and Mean Square Error ? Are they the same thing?
I have a bit of confusion regarding ASE and MSE as in SAS Enterprise Miner it shows these two measurement scales. What is the difference or similarity between the two and why are they both so similar? ...
1
vote
2answers
89 views
Material/courses for analyzing very large data sets
I am looking for good materials to learn more about analyzing very large data sets, say 5 million observations, with a reasonable computational time (say less than 10h).
My main interests is ...
0
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0answers
12 views
SAS: joint model with proc glimmix
I am attempting to perform a joint generalized linear mixed model with one binary variable and one continuous variable with proc glimmix. The preferred random effects structure for my binary variable ...
0
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0answers
53 views
How do you solve this error Within-imputation Estimate missing for effect ... in the input PARMS = dataset.?
I am fitting a mixed-effects logistic model using PROC GLIMMIX. All the variables I am working with are either binary of categorical. Because there were a few variables that had 10% or more of missing ...
0
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0answers
26 views
Time Series in SAS getting contradiction?
The 2td graph shows auto-correlation function has significantly zero value after 10-ish but the table which checks nullity correlation says it has auto-correlation not-equal to 0 for lag=24 unlike to ...
0
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0answers
58 views
When does parameterization and LSMEANS vs ESTIMATE in SAS PROC GENMOD make a difference in exponentiated Beta, confidence interval, and p value?
I am running a modified Poisson regression (Poisson with robust standard errors) to estimate prevalence ratios (ie relative risk). I am a bit confused about whether PARAM= choice and LSMEANS vs ...
0
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0answers
12 views
How to replicate statistical significance in STEPAR method of SAS PROC FORECAST?
This is basically a trend model + Autoregressive Error model
Figuring out the coefficients for the AR model is just a straightforward application of Yule-Walker equations. However, not sure about how ...
0
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0answers
16 views
Spatial Regression using PROC GLIMMIX
I'm experienced using PROC GLIMMIX, but I don't have expertise in spatial analysis. I have data that is at the FIPS (county) level. I'm interested in running a negative binomial regression model using ...
0
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0answers
14 views
SAS PROC Forecast - Underlying steps in STEPAR Algorithm
I am trying to understand following algorithm, but am having some trouble understanding what's happening under the hood starting from step 3. Would appreciate any insight into how this works.
...
0
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0answers
19 views
Missing values in multiple regression with SAS
I am working on my first linear regression project in SAS and I wanted to ask some advice.
My dataset consists of a sample of 428 automotive vehicles from the same production year that was collected ...
0
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0answers
22 views
Best Method for Continuous Target
I am trying to build a model where my target is continuous with a
right-skewed distribution. I am interested to know what are possible
models I can try apart from linear regression.
I have around 200 ...
0
votes
0answers
14 views
How to restrict number of knots for individual variable in SAS PROC ADAPTIVEREG procedure
I am trying to use SAS PROC ADAPTIVEREG to do a variable selection and search for optimal knot position for spline transformation. One question that I encounter is how to, if possible, restrict the ...
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0answers
15 views
Monotone imputation PROC MI (SAS) and mice (R)
I am having trouble understanding the theory behind multiple imputation (MI). I am focusing on monotone missing patterns and I have to explain the concept to my colleagues. SAS and MICE documentation ...
0
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0answers
28 views
In binary logistic regression, how do you interpret a categorical-by-categorical interaction term?
I am working with multiply imputed data and I have run a logistic regression model with 6 predictors (3 dichotomous and 3 categorical) and their interaction terms, controlling for a number relevant ...
0
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0answers
18 views
What is "categorical target variable" in SAS EM
"A categorical target variable that has exactly two categories (i.e., a binary or dichotomous variable)."
What is "categorical target variable" in the SAS EM space? Is this ...
2
votes
1answer
32 views
Why use a stratified log-rank test if we balance over strata anyway?
When comparing survival data over time, we can use the log-rank test. An extension of this is the stratified log-rank test, which adjusts for variables.
Let's say we wanted to adjust for the effect of ...
1
vote
0answers
15 views
Sobel test for a mixed design experiment
Hi I have a mixed design experiment with 1 within subjects factor (4 levels) and 1 between subjects factor (4 levels). The following diagram shows a summary of the model that I am trying to test (...
0
votes
0answers
23 views
Pattern-mixture models in SAS
I've been asked to implement a pattern-mixture model using non-future dependent missing value restrictions (NFMV) as a sensitivity analysis for missing data.
It appears as though SAS's PROC MI ...
0
votes
1answer
50 views
How to operationalize stratified, cluster survey sample “standard of the mean” in Excel
I have a question on the analysis of complex survey design. Basically, I am trying to replicate the SAS Surveymeans procedure in Excel in order to understand how to operationalize the equations to ...
1
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0answers
9 views
Tuning the Logit model based on sensitivity
I am working on a logistic model to predict whether or not an employee is likely to take a leave day during a given three month period. The model only correctly classified the “non-event"
...
1
vote
2answers
47 views
Interaction term with categorical predictors with more than one level
I am looking at the interaction between education (LTHS, HS, SOME COLLEGE, COLLEGE) and race (WHITE, BLACK, HISPANIC, ASIAN, NATIVE AMERICAN). I am using SAS and am including a class statement in my ...
0
votes
1answer
408 views
Post hoc test for Fisher's exact test (larger than 2x2)?
I have 2 categorical variables: Var1 - 3 levels, Var2- 5 levels (i.e., table is bigger than 2x2). I'm using SAS, and since I have multiple cells <5, I have run a Fisher's exact test with Monte ...
0
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0answers
15 views
Matching output from PROC glm in SAS to lme in the nlme package in R
I have a nested design with a fixed factor (Status) at the top. Nested in Status is Population, and nested in Population is Family. There are a few different responses I am fitting to this. In SAS, ...
1
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0answers
41 views
Lasso Application in SAS
I have a question regarding the Lassoapplication in SAS using cross validation method (choose =cvex and stop=none). I test different regression models and very often Lasso keeps all the variables such ...
0
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0answers
40 views
Understanding the Chi Squared test for Significance Analysis of Unobserved Components in SAS' Proc UCM
Proc UCM in SAS does a Chi Squared test to test the significance of the components found by fitting a UCM model. I want to understand what exactly this test is and how to interpret it. As in, what is ...
0
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0answers
32 views
Interaction term not significant but post-hoc tests are
I'm running a GEE model in SAS with an interaction term between two categorical variables group2 and lbl. Running a joint test, ...
1
vote
2answers
84 views
Can an odd ratio be as low as $< 0.001$?
With a 95% CI of $< 0.001$ to $> 999.999$? Any idea what could be wrong?
(Sorry about the french output, will gladly provide more info if needed)
Thanks a lot!
0
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0answers
15 views
out of sample prediction standard error and confidence limit using bootstrap
I am analyzing growth data to determine if sibling competition affect growth using GLIMMIX procedure in SAS with different class and continuous variables and 2 random effects. I want to predict out of ...
0
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0answers
43 views
Multiple imputation using proc mi EM method in SAS
I'd like to clarify how to use SAS for (multiple) imputation in SAS, specifically the EM method option for proc mi. Do I need to analyze multiple imputed sets using proc mianalyze as mentioned in ...
2
votes
1answer
172 views
Why does median() differ from quantile()["50%"] in R and doesn't honor the type? Is this an estimator or sample quantile?
I just found, that when I want a specific type of quantile in R, say the number 3, it doesn't agree with median calculated in the "traditional way" in R.
...
0
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0answers
132 views
LASSO Regression with AIC or BIC as Model Selection Criterion
I am fitting a linear model using LASSO and exploring BIC (or AIC) as the selection criterion. The most useful resource I have stumbled upon is this earlier question here on CrossValidated: Is it ...
0
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0answers
176 views
Restricted Cubic Splines - Test Non-linearity in SAS
In SAS, I am having a very difficult time performing a formal test of non-linearity for the effect of one continuous variable estimated using restricted cubic splines. Yes, I know this is easy to ...
0
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0answers
43 views
Sample size for binary outcome and continuous (%) predictor
I have a project in which I have 60-70 samples.
Outcome = binary (positive or negative case)
Exposure = % of the time participants followed new guidelines (0-100%)
Question - would it be correct to ...
0
votes
2answers
189 views
Binary independent variables with missing values. Create dummy variables or not?
I am developing a prognostic model to predict an outcome. I have few binary variables with missing values, see below example. Is it better if I create dummy variables out of the below Gender variable ...
0
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0answers
28 views
Translate Mixed Models syntax from SAS to R (rewrite SAS proc mixed to R lmer)
Can anyone help me, please, to implement the SAS mixed model presented below in R lmer syntax?
How to interpret such a model?
<...
0
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0answers
4 views
Sas linear regression deciding on subgroups
I want to model the Total Volume as a function of the two variables Units and Price.
I want to find out whether to model the total volume on the category as a whole or whether to model total volume by ...
0
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0answers
9 views
What type of statistical test should I perform?
What statistical technique would I need to carry out if I want to see if there is a significant differences in the number of units purchased when classifying observations based the variables Age, ...
0
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0answers
10 views
Comparing rates of hospital admissions or refusal rates year against year
I am trying to design a study for introducing a treatment and seeing if this would change rates of admission or leaving the hospital against medical advice. I would compare Jan-Dec 2020 (no tx offered)...
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0answers
8 views
SAS principal component analysis help [closed]
I have performed a principal component analysis on sas and have but my 15 variables into 4 factors so I have 4 new constructs. I now want to find out which of the original variables were important in ...