Nilam Ram, PhD

Director, QuantDev
Professor of Human Development and Psychology

My research interests have grown out of a history of studying change. After finishing an undergraduate degree in economics at Columbia University I worked as a foreign currency derivatives trader. There, I studied the movement of world markets as they went up, went down, and went sideways. My formal study of change processes continued with an MS in kinesiology at the University of Colorado, and a PhD in quantitative psychology at the University of Virginia. I specialize in longitudinal research methodology and life-span development – particularly in how within-person/intraindividual change and variability study designs can contribute to our understanding of human behavior. My goals are to develop and apply novel longitudinal methods that address fundamental questions pertaining to human development. I make use of and am extending a variety of techniques for analyzing change, with primary focus on multivariate time-series and growth curve modeling. Substantively, I apply these methods to examine changes in human behavior at multiple levels – biological, behavioral, cultural – and across multiple time scales – second-to-second, day-to-day, decade-to-decade. A key element of my research program is the explicit interplay between developmental theory, method, and data. I use the methodological innovations to challenge, extend, and demonstrate the need for greater precision in the current theoretical viewpoints, while at the same time using the theoretical viewpoints to further reconceptualize how analytical methods can be adapted and applied to the study of individual-level processes. Coupling the theory and method with data collected using mobile technologies we are contributing to a paradigm shift towards person-specific methodology and the delivery of individualized interventions/treatment. The work encompasses and integrates data collected at both ‘slow’ and ‘fast’ time-scales – the former describing long-term developmental change; the latter elucidating the behavioral and biological mechanisms that drive developmental change.

Contributed Tutorials

Publications

Gatzke-Kopp, L. M., Ram, N., Lydon-Staley, D. M., & DuPuis, D.. (2018). Children's Sensitivity to Cost and Reward in Decision Making across Distinct Domains of Probability, Effort, and Delay. Journal of Behavioral Decision Making, 31, 12 - 24. presented at the Jan-01-2018. doi:10.1002/bdm.v31.110.1002/bdm.2038
Benson, L., Ram, N., & Stifter, C. A.. (2018). Using Fishery Models to Examine Self- and Co-Regulation Processes Across Multiple Timescales. Structural Equation Modeling: A Multidisciplinary Journal, 1 - 18. doi:10.1080/10705511.2018.1491313
Chiatti, A., Yang, X., Brinberg, M., Cho, M. Jung, Gagneja, A., Ram, N., et al.. (2017). Text Extraction from Smartphone Screenshots to Archive in situ Media Behavior. In The Knowledge Capture Conference. presented at the 12/2017, Austin, TX, USANew York, New York, USA: ACM Press. doi:10.1145/314801110.1145/3148011.3154468
Lydon-Staley, D. M., Ram, N., Brose, A., & Schmiedek, F.. (2017). Reduced impact of alcohol use on next-day tiredness in older relative to younger adults: A role for sleep duration. Psychology and Aging, 32(7), 642 - 653. presented at the Jan-11-2017. doi:10.1037/pag0000198
Ong, A. D., Benson, L., Zautra, A. J., & Ram, N.. (2017). Emodiversity and Biomarkers of Inflammation. Emotion. presented at the Jan-01-2017. doi:10.1037/emo0000343
Wood, J., Oravecz, Z., Vogel, N., Benson, L., Chow, S. - M., Cole, P., et al.. (2017). Modeling Intraindividual Dynamics Using Stochastic Differential Equations: Age Differences in Affect Regulation. The Journals of Gerontology: Series B. presented at the Feb-03-2017. doi:10.1093/geronb/gbx013
Ram, N., Brinberg, M., Pincus, A. L., & Conroy, D. E.. (2017). The Questionable Ecological Validity of Ecological Momentary Assessment: Considerations for Design and Analysis. Research in Human Development, 1411(3), 253 - 270. presented at the Mar-07-2017. doi:10.1080/15427609.2017.1340052
Brick, T. R., Koffer, R., Gerstorf, D., & Ram, N.. (2017). Feature Selection Methods for Optimal Design of Studies for Developmental Inquiry. The Journals of Gerontology: Series B, 73(1), 113 - 123. presented at the Jun-02-2017. doi:10.1093/geronb/gbx008
Benson, L., Ram, N., Almeida, D. M., Zautra, A. J., & Ong, A. D.. (2017). Fusing Biodiversity Metrics into Investigations of Daily Life: Illustrations and Recommendations With Emodiversity. The Journals of Gerontology: Series B. presented at the Jun-03-2019. doi:10.1093/geronb/gbx025
Scott, S. B., Ram, N., Smyth, J. M., Almeida, D. M., & Sliwinski, M. J.. (2017). Age differences in negative emotional responses to daily stressors depend on time since event. Developmental Psychology, 53(1), 177 - 190. presented at the Jan-01-2017. doi:10.1037/dev0000257
Koffer, R., Ram, N., & Almeida, D. M.. (2017). More than Counting: An Intraindividual Variability Approach to Categorical Repeated Measures. The Journals of Gerontology: Series B, 73(1), 87 - 99. presented at the Mar-09-2019. doi:10.1093/geronb/gbx086
Cole, P. M., Bendezú, J. J., Ram, N., & Chow, S. - M.. (2017). Dynamical Systems Modeling of Early Childhood Self-Regulation. Emotion. presented at the Jan-01-2017. doi:10.1037/emo0000268
Brinberg, M., Fosco, G. M., & Ram, N.. (2017). Examining inter-family differences in intra-family (parent–adolescent) dynamics using grid-sequence analysis.. Journal of Family Psychology, 31(8), 994 - 1004. presented at the Jan-12-2017. doi:10.1037/fam0000371
Infurna, F. J., Gerstorf, D., Ram, N., & Heckhausen, J.. (2016). Analytic Strategies for the Study of Adaptation to Major Life Events: Making the Most of Large-Scale Longitudinal Surveys. In H. - P. Blossfeld, von Maurice, J., Bayer, M., & Skopek, J., Methodological Issues of Longitudinal Surveys (pp. 19 - 35). Wiesbaden: Springer Fachmedien Wiesbaden. doi:10.1007/978-3-658-11994-2_2
Lippold, M. A., Fosco, G. M., Ram, N., & Feinberg, M. E.. (2016). Knowledge Lability: Within-Person Changes in Parental Knowledge and Their Associations with Adolescent Problem Behavior. Prevention Science, 17(2), 274 - 283. presented at the Jan-02-2016. doi:10.1007/s11121-015-0604-5
Weybright, E. H., Caldwell, L. L., Ram, N., Smith, E. A., & Wegner, L.. (2016). Trajectories of adolescent substance use development and the influence of healthy leisure: A growth mixture modeling approach. Journal of Adolescence, 49, 158 - 169. presented at the Jan-06-2016. doi:10.1016/j.adolescence.2016.03.012
Schöllgen, I., Morack, J., Infurna, F. J., Ram, N., & Gerstorf, D.. (2016). Health sensitivity: Age differences in the within-person coupling of individuals’ physical health and well-being.. Developmental Psychology, 52(11), 1944 - 1953. presented at the Jan-01-2016. doi:10.1037/dev0000171
Gerstorf, D., Hoppmann, C. A., Löckenhoff, C. E., Infurna, F. J., Schupp, ürgen, Wagner, G. G., & Ram, N.. (2016). Terminal decline in well-being: The role of social orientation. Psychology and Aging, 31(2), 149 - 165. presented at the Jan-01-2016. doi:10.1037/pag0000072
Chow, S. - M., Bendezú, J. J., Cole, P. M., & Ram, N.. (2016). A Comparison of Two-Stage Approaches for Fitting Nonlinear Ordinary Differential Equation Models with Mixed Effects. Multivariate Behavioral Research, 51(2-3), 154 - 184. presented at the Mar-05-2016. doi:10.1080/00273171.2015.1123138
Lee, S., Koffer, R., Sprague, B. N., Charles, S. T., Ram, N., & Almeida, D. M.. (2016). Activity Diversity and Its Associations With Psychological Well-Being Across Adulthood. The Journals of Gerontology Series B: Psychological Sciences and Social Sciences, gbw118. presented at the Dec-09-2016. doi:10.1093/geronb/gbw118
Brinberg, M., Ram, N., Hülür, G., Brick, T. R., & Gerstorf, D.. (2016). Analyzing Dyadic Data Using Grid-Sequence Analysis: Interdyad Differences in Intradyad Dynamics. The Journals of Gerontology Series B: Psychological Sciences and Social Sciences, gbw160. presented at the May-12-2018. doi:10.1093/geronb/gbw160
Helm, J. Lee, Ram, N., Cole, P. M., & Chow, S. - M.. (2016). Modeling Self-Regulation as a Process Using a Multiple Time-Scale Multiphase Latent Basis Growth Model. Structural Equation Modeling: A Multidisciplinary Journal, 23(5), 635 - 648. presented at the Feb-09-2016. doi:10.1080/10705511.2016.1178580
Infurna, F. J., Gerstorf, D., Ram, N., Schupp, J., Wagner, G. G., & Heckhausen, J.. (2016). Maintaining perceived control with unemployment facilitates future adjustment. Journal of Vocational Behavior, 93, 103 - 119. presented at the Jan-04-2016. doi:10.1016/j.jvb.2016.01.006
Koffer, R., Ram, N., Conroy, D. E., Pincus, A. L., & Almeida, D. M.. (2016). Stressor diversity: Introduction and empirical integration into the daily stress model. Psychology and Aging, 31(4), 301 - 320. presented at the Jan-01-2016. doi:10.1037/pag0000095
Ram, N., & Grimm, K. J.. (2015). Growth Curve Modeling and Longitudinal Factor Analysis. In R. M. Lerner, Handbook of Child Psychology and Developmental Science (pp. 1 - 31). Hoboken, NJ, USA: John Wiley & Sons, Inc. doi:10.1002/978111896341810.1002/9781118963418.childpsy120
Koffer, R., & Ram, N.. (2015). Intraindividual Variability. In S. Krauss Whitbourne, Encyclopedia of Adulthood and Aging (pp. 683-688). Hoboken, NJ, USA: John Wiley & Sons, Inc. doi:10.1002/9781118521373.wbeaa247
Tuarob, S., Tucker, C. S., Salathe, M., & Ram, N.. (2015). Modeling Individual-Level Infection Dynamics Using Social Network Information. In J. Bailey, Moffat, A., Aggarwal, C. C., de Rijke, M., Kumar, R., Murdock, V., et al., the 24th ACM InternationalProceedings of the 24th ACM International on Conference on Information and Knowledge Management - CIKM '15. Melbourne, AustraliaNew York, New York, USA: ACM Press. doi:10.1145/280641610.1145/2806416.2806575
Conroy, D. E., Ram, N., Pincus, A. L., & Rebar, A. L.. (2015). Bursts of Self-Conscious Emotions in the Daily Lives of Emerging Adults. Self and Identity, 14(3), 290 - 313. presented at the Apr-05-2015. doi:10.1080/15298868.2014.983963
Conroy, D. E., Ram, N., Pincus, A. L., Coffman, D. L., Lorek, A. E., Rebar, A. L., & Roche, M. J.. (2015). Daily physical activity and alcohol use across the adult lifespan. Health Psychology, 34(6), 653 - 660. presented at the Jan-01-2015. doi:10.1037/hea0000157
Maher, J. P., Pincus, A. L., Ram, N., & Conroy, D. E.. (2015). Daily physical activity and life satisfaction across adulthood. Developmental Psychology, 51(10), 1407 - 1419. presented at the Jan-01-2015. doi:10.1037/dev0000037
Tuarob, S., Tucker, C. S., Salathe, M., & Ram, N.. (2014). An ensemble heterogeneous classification methodology for discovering health-related knowledge in social media messages. Journal of Biomedical Informatics, 49, 255 - 268. presented at the Jan-06-2014. doi:10.1016/j.jbi.2014.03.005
Ram, N., Shiyko, M., Lunkenheimer, E. S., Doerksen, S., & Conroy, D.. (2013). Families as Coordinated Symbiotic Systems: Making use of Nonlinear Dynamic Models. In S. M. McHale, Amato, P., & Booth, A., (Vol. 4, pp. 19 - 37). Cham: Springer International Publishing. doi:10.1007/978-3-319-01562-010.1007/978-3-319-01562-0_2