Application of Two-Level Negative Exponential Model to Children's Learning Curve in Reading

Abstract

This paper attempts to model the development of children's reading skills using the negative exponential curve with mixed effects model. The model describes the nature of growth in children's reading skills and accounts for intra-individual and 279 MARCEL DEKKER, INC. • 270 MADISON AVENUE • NEW YORK, NY 10016inter-individual variations. In addition, we propose methods including cross-validation, regression, and graphing to determine an appropriate curve for the data, to find good initial values for parameters, and to select potential covariates. We illustrate with an example that motivated this research: a longitudinal study of academic reading skills from grade 1 to grade 12 in Connecticut public schools.

Vitamin D status and immune function reconstitution in HIV-infected men initiating therapy

“…CD4 rebound was modelled using a nonlinear mixed effects model which described the process of CD4 increase as an exponential function of time since HAART initiation [31,32]. The model had three parameters which included the starting CD4 (starting count; S) at HAART initiation, the plateau or final level of CD4 (final count; F) following recovery, and the rate at which CD4 increased (rate of increase; R).…”