the aim of this study is designing a model for the optimal development of human resources in academic libraries. to this end, the university of tehran library as a case study is investigated. with regard to the four independent variables- organizational structure, organizational culture, leadership and strategic perspective, and mediator variables of attitude, behavior and creativity of staff- ...

OBJECTIVE To provide examples of post-hoc probing of significant moderator and mediator effects in research on children with pediatric conditions. METHODS To demonstrate post-hoc probing of moderational effects, significant two-way interaction effects (dichotomous variable x continuous variable; continuous variable x continuous variable) were probed with regressions that included conditional ...

In a simple mediation model, the effect of a manipulated variable X on a dependent variable Y over and above the effect of the mediator Me can be estimated by regressing Y on X and Me. The impact of X on Y in such a model is adjusted for the relationship both between X and Me and between Me and Y . The authors examine the adjustment function in the context of a 2× 2 design with two manipulated ...

Recent statistical mediation analysis research focuses on using Bayesian methods for several reasons including the ability to incorporate prior information about model parameters, ease of constructing intervals for simple and complex models, and exact inference for small samples without restrictive assumptions of conventional mediation analysis (Yuan & MacKinnon, 2009).The focus of this paper i...

BACKGROUND Mendelian randomization uses genetic variants, assumed to be instrumental variables for a particular exposure, to estimate the causal effect of that exposure on an outcome. If the instrumental variable criteria are satisfied, the resulting estimator is consistent even in the presence of unmeasured confounding and reverse causation. METHODS We extend the Mendelian randomization para...

This article presents marginal structural models with inverse propensity weighting (IPW) for assessing mediation. Generally, individuals are not randomly assigned to levels of the mediator. Therefore, confounders of the mediator and outcome may exist that limit causal inferences, a goal of mediation analysis. Either regression adjustment or IPW can be used to take confounding into account, but ...