Nick has a paper in the American Statistician warning about bias in multiple imputation arising from rounding data imputed under a normal assumption. One example where you might run afoul of this is if the data are truly dichotomous or count variables...

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Tags: mice package, mice(), multiple imputation, pool(), predictive mean matching, proc mi, proc mianalyze, rand function, rnorm(), rounding, Stuart Lipsitz

Posted in SAS | Comments Off on Example 9.33: Multiple imputation, rounding, and bias

We often work in settings where the data set has a lot of missing data-- some missingness in the (many) covariates, some in the main exposure of interest, and still more in the outcome. (Nick describes this as "job security for statisticians").Some ana...

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Tags: assumptions, comparing models, customizing plots, graphics, missing data modeling, multiple imputation

Posted in SAS | Comments Off on Example 9.6: Model comparison plots (Completed)

We often work in settings where the data set has a lot of missing data-- some missingness in the (many) covariates, some in the main exposure of interest, and still more in the outcome. (Nick describes this as "job security for statisticians").Some ana...

Read more »

Tags: assumptions, comparing models, customizing plots, graphics, missing data modeling, multiple imputation

Posted in SAS | Comments Off on Example 9.6: Model comparison plots (Completed)

We often work in settings where the data set has a lot of missing data-- some missingness in the (many) covariates, some in the main exposure of interest, and still more in the outcome. (Nick describes this as "job security for statisticians").Some ana...

Read more »

Tags: assumptions, comparing models, customizing plots, graphics, missing data modeling, multiple imputation

Posted in SAS | Comments Off on Example 9.6: Model comparison plots (Completed)

We begin the new academic year with a series of entries exploring new capabilities of SAS 9.3, and some functionality we haven't previously written about.We'll begin with multiple imputation. Here, SAS has previously been limited to multivariate norma...

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Tags: multiple imputation, non-monotonic missingness, proc mi

Posted in SAS | Comments Off on Example 9.4: New stuff in SAS 9.3– MI FCS

We begin the new academic year with a series of entries exploring new capabilities of SAS 9.3, and some functionality we haven't previously written about.We'll begin with multiple imputation. Here, SAS has previously been limited to multivariate norma...

Read more »

Tags: multiple imputation, non-monotonic missingness, proc mi

Posted in SAS | Comments Off on Example 9.4: New stuff in SAS 9.3– MI FCS

We begin the new academic year with a series of entries exploring new capabilities of SAS 9.3, and some functionality we haven't previously written about.We'll begin with multiple imputation. Here, SAS has previously been limited to multivariate norma...

Read more »

Tags: multiple imputation, non-monotonic missingness, proc mi

Posted in SAS | Comments Off on Example 9.4: New stuff in SAS 9.3– MI FCS