Ruby Johnson is a research statistician at RTI where she samples, weighs, and analyzes various sizes of surveys. She performs item imputations using weighted and unweighted hot-desk techniques. She is skilled in the construction of response-adjusted and post-stratified analysis weights, balanced repeated replications weights, and jackknife weights using weighting class adjustments and generalized exponential models.
Currently, Ms. Johnson works on the National Postsecondary Student Aid Study (NPSAS) as a sampling and statistics task leader. She manages a statistical team on sampling, weights, imputations, nonresponse bias analysis, and nondisclosures to provide comprehensive data on student financial aid. She also works on the Medical Expenditure Panel Survey (MEPS), where she leads the statistical activities for the identification of duplicate records. Ms. Johnson is responsible for developing and maintaining complex algorithms to place providers into contact groups for data collection staff. Additionally, she performs edit checks and prepares spreadsheets to be reviewed for data consistency.
Ms. Johnson joined RTI in 1999 and has been a key contributor to decade long projects. She uses SAS and SUDAAN on numerous large data sets for producing descriptive analyses, standardized comparisons, and multivariate models using linear and logistic regression.