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Purpose: Social distancing strategies such as “stay-at-home” (SAH) orders can slow the transmission of contagious viruses like the SARS-CoV-2 virus, but require population adherence to be effective.
Methods and Measures: Growth mixture modeling: A method for identifying differences in longitudinal change among unobserved groups
  • N. Ram, K. Grimm
  • Psychology, Medicine
    International journal of behavioral development
  • 26 October 2009
This work provides a practical primer that may be useful for researchers beginning to incorporate GMM analysis into their research and introduces GMM as an extension of multiple-group growth modeling.
Emotional experience improves with age: evidence based on over 10 years of experience sampling.
Cross-sectional and growth curve analyses indicate that aging is associated with more positive overall emotional well-being, with greater emotional stability and with more complexity (as evidenced by greater co-occurrence of positive and negative emotions).
Time-structured and net intraindividual variability: tools for examining the development of dynamic characteristics and processes.
This article provides a descriptive frame for the combined study of intraindividual variability and aging/development and points to the benefits of measurement-burst study designs, wherein data are obtained across multiple time scales, for the study of development.
A daily analysis of physical activity and satisfaction with life in emerging adults.
It is concluded that SWL was impacted by people's daily PA rather than their trait level of PA over time and should be considered when developing national policies to enhance SWL.
Saving energy in an office environment: A serious game intervention
Abstract Serious Games are virtual simulations of real-world activities that can both educate users and prompt behavioral change. This study evaluated the effectiveness of a virtual pet game in
Nonlinear Growth Models in Mplus and SAS
  • K. Grimm, N. Ram
  • Psychology, Medicine
    Structural equation modeling : a…
  • 6 October 2009
This article describes how a variety of sigmoid curves can be fit using the Mplus structural modeling program and the nonlinear mixed-effects modeling procedure NLMIXED in SAS.
An ensemble heterogeneous classification methodology for discovering health-related knowledge in social media messages
This paper aims to address the limitations posed by the traditional bag-of-word based methods and propose to use heterogeneous features in combination with ensemble machine learning techniques to discover health-related information, which could prove to be useful to multiple biomedical applications.
Automatic search for fMRI connectivity mapping: An alternative to Granger causality testing using formal equivalences among SEM path modeling, VAR, and unified SEM
This paper demonstrates how the unified SEM attends to both lagged and contemporaneous influences on ROI activity and offers an approach akin to Granger causality testing, Lagrange multiplier testing, for statistically identifying directional influence among ROIs and employs this approach using an automatic search procedure to arrive at the optimal model.
Self-Modeling: Influence on Psychological Responses and Physical Performance
Although self-modeling has been effective in modifying behaviors in a variety of settings, little research has been completed in the physical domain. The purpose of this study was to test the