The linear correlation coefficient is typically used to characterize and analyze dependencies of neural spike counts. Here, we show that the correlation coefficient is in general insufficient to characterize these dependencies. We construct two neuron spike count models with Poisson-like marginals and vary their dependence structure using copulas. To this end, we construct a copula that allows ...

The central purpose of this paper is to formulate and estimate a retirement model that also includes claiming of Social Security benefits as an outcome, and to use the model to inquire about the effects of various proposals to change the Social Security system. The forerunner to this work is a retirement model previously built to capture the spike in retirement at the Social Security early enti...

RetinotopicNET is an efficient simulator for neural architectures with retinotopic-like receptive fields. The system has two main characteristics: it is event-driven and it takes advantage of the retinotopic arrangement in the receptive fields. The dynamics of the simulator are driven by the spike events of the simple integrate-and-fire neurons. By using an implicit synaptic rule to represent t...

A novel statistical strategy, the spike jitter method, was developed to assess temporal structure in spike trains from neuronal ensembles. Its key feature is the introduction of a null hypothesis that assumes a uniform relative likelihood of observing a spike at one temporal location versus another within a small temporal window. We applied the method to simultaneously recorded motor cortical n...

Increasing atmospheric CO2 concentration has led to concerns about potential effects on production agriculture as well as agriculture’s role in sequestering C. In the fall of 1997, a study was initiated to compare the response of two crop management systems (conventional and conservation) to elevated CO2. The study used a split-plot design replicated three times with two management systems as m...