Multiple imputation by chained equations is a flexible and practical approach to handling missing data. We describe the principles of the method and show how to impute categorical and quantitative variables, including skewed variables. We give guidance on how to specify the imputation model and how many imputations are needed. We describe the practical analysis of multiply imputed data, including model building and model checking. We stress the limitations of the method and discuss the possible pitfalls. We illustrate the ideas using a data set in mental health, giving Stata code fragments. Copyright © 2010 John Wiley & Sons, Ltd.

Multiple imputation using chained equations: Issues and guidance for practice

As long-term opioid therapy for chronic noncancer pain is becoming more common in community practice, rates of fatal opioid overdose have increased. Dunn and coworkers found that 51 of 9940 adults ...

https://rsds.org/wp-content/uploads/2015/02/DunnKM_AnnInternMed_2010.pdf

Opioid Prescriptions for Chronic Pain and Overdose

Biodiversity is rapidly declining, and this may negatively affect ecosystem processes, including economically important ecosystem services Previous studies have shown that biodiversity has positive effects on organisms and processes across trophic levels However, only a few studies have so far incorporated an explicit food-web perspective In an eight-year biodiversity experiment, we studied an unprecedented range of above- and below-ground organisms and multitrophic interactions A multitrophic data set originating from a single long-term experiment allows mechanistic insights that would not be gained from meta-analysis of different experiments Here we show that plant diversity effects dampen with increasing trophic level and degree of omnivory This was true both for abundance and species richness of organisms Furthermore, we present comprehensive above-ground/below-ground biodiversity food webs Both above ground and below ground, herbivores responded more strongly to changes in plant diversity than did carnivores or omnivores Density and richness of carnivorous taxa was independent of vegetation structure Below-ground responses to plant diversity were consistently weaker than above-ground responses Responses to increasing plant diversity were generally positive, but were negative for biological invasion, pathogen infestation and hyperparasitism Our results suggest that plant diversity has strong bottom-up effects on multitrophic interaction networks, with particularly strong effects on lower trophic levels Effects on higher trophic levels are indirectly mediated through bottom-up trophic cascades

/pdf/bottom-up-effects-of-plant-diversity-on-multitrophic-37h0k34b1u.pdf

Bottom-up effects of plant diversity on multitrophic interactions in a biodiversity experiment

http://www.biac.duke.edu/library/papers/2009_NeuroImage_Morey.pdf

A comparison of automated segmentation and manual tracing for quantifying hippocampal and amygdala volumes

This paper documents the design, layout and algorithms of the IUPAC International Chemical Identifier, InChI.

/pdf/inchi-the-iupac-international-chemical-identifier-359hsmsndg.pdf

InChI, the IUPAC International Chemical Identifier

OUTPU T 29 OUTPU T 30 OUTPU T 31 OUTPU T 32 OUTPU T 25 OUTPU T 26 OUTPU T 27 OUTPU T 28 OUTPU T 21 OUTPU T 22 OUTPU T 23 OUTPU T 24 OUTPU T 17 OUTPU T 18 OUTPU T 19 OUTPU T 20 OUTPU T 13 OUTPU T 14 OUTPU T 15 OUTPU T 16 OUTPU T 9 OUTPU T 10 OUTPU T 11 OUTPU T 12 OUTPU T 5 OUTPU T 6 OUTPU T 7 OUTPU T 8 OUTPU T 1 OUTPU T 2 OUTPU T 3 OUTPU T 4 29 30 31 32 25 26 27 28 21 22 23 24 17 18 19 20 13 14 15 16 9

Robert S. Leiken

Papers

A User’s Guide