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.
720
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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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4
votes
1
answer
170
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Doubts about mixed model (R vs SAS) with nested random effects [closed]
I use SAS to fit a simple mixed model where there is nested random effects of Block within Location like this:
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5
votes
1
answer
155
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How should I analyse this experiment with two blocking factors
In this experiment, a machine is used to compare the wear resistance of 4 different types of rubber-coated fabric (variable mat coded A, B, C and D). To do this, ...
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3
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1
answer
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What is a Randomized Complete Block Design. How do we create one and analyze it?
I have been reading about experimental design, and Randomized Complete Block designs (RCBD) in particular and I have a few queries. What exactly is a randomized complete block design ? Is there a ...
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0
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144
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Correspondence between SAS proc surveyreg and R svyglm [closed]
I am trying to model my proc surveyreg from SAS in R, because their survey package provides an IV option that I intend to use.
<...
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1
vote
1
answer
231
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In SAS what is the difference of including treatment variable in model and using the strata statement for treatment variable?
Im building a Cox Regression in SAS. My code looks like this:
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2
votes
0
answers
40
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How to solve MME [closed]
I have spent an entire day trying to figure out how to solve these mixed model equations without any luck. I am therefore reaching out to this community. The assignment is as follows:
Using the ...
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6
votes
1
answer
135
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Understanding SAS Mixed Model Syntax
I'm used to specifying mixed models with mathematical notation or in R using the lme4 syntax. Now, I was asked to review a mixed model fitted in SAS. The SAS model ...
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0
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19
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Analyzing discrete Proportional Data with different sample sizes in GLMM?
I am reaching out to seek guidance regarding an issue that has been troubling me for a while.
In my study, I had participants choose a strategy for expressing 6 different emotions across * 5 social ...
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0
votes
2
answers
102
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Difference of output in Chi-square in SAS and R
Currently I have a dataset with an N of 3866 with two variables, Project (group variable, six levels) and Topbox (two levels; yes, no). We are looking to see if there is a difference in the proportion ...
1
vote
0
answers
214
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Games-Howell multiple comparisons test in SAS
I am looking to determine whether patient's total number of prescriptions (RxTotal) differs by membership within 3 possible groups (ie run an ANOVA), and if so, to determine which groups differ (ie ...
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2
votes
1
answer
36
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Need some help/guidance on GLMM questions
Newbie with linear mixed modelling here. Need some advice/help on my problem detailed below.
Dataset below with assessments taken at different visits: baseline (visit=1), and then at 30 days, 60 days ...
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Rate of lost to follow-up at first year
Is this the correct way to calculate the rate of lost to follow-up at first year?
Rate of lost to follow-up at first year= rate of censored subjects at firstyear.
There is no specific method for that ...
- 3
0
votes
0
answers
98
views
How to calculate the sample size when compare rate using Poisson regression?
I have a question regarding the sample size calculation if I want to compare rates using Poisson regression. I want to compare the rate of book A to the rate of book B. The rate of book A is defined ...
- 51
0
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0
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27
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Calculating Inter-Observer Reliability when not all categories are scored
I have two main questions:
1) Is there a way to calculate IRR when the range of scores differ between observers? If not, how do you get IRR without excluding data?
I am calculating inter-observer ...
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