For a binary outcome Y, generated by simple threshold crossing model with single exogenous normally distributed explanatory variable X, the OLS estimator of coefficient on X in linear probability is consistent average partial effect X. Even this very setting, we show that when allowing for to be endogenously determined, 2SLS estimator, using instrumental Z, does not identify same causal paramet...

This paper presents a hyperbolic trigonometric (HT) transformation procedure for empirically estimating a cumulative probability distribution function (cdf), from which the probability density function (pdf) can be obtained by differentiation. Maximum likelihood (ML) is the appropriate estimation technique, but a particularly appealing feature of the HT transformation as opposed to other zero-o...

MicroRNAs (miRs) regulate diverse molecular and cellular processes including oligodendrocyte (OL) precursor cell (OPC) proliferation and differentiation in rodents. However, the role of miRs in human OPCs is poorly understood. To identify miRs that may regulate these processes in humans, we isolated OL lineage cells from human white matter and analyzed their miR profile. Using endpoint RT-PCR a...

Oligodendrocytes (OLs) are in many ways implicated in the pathophysiology of schizophrenia. However, very little is currently known about possible OL cell cycle disturbances in schizophrenia, a phenomenon which has been described for the birth of new hippocampal neurons in schizophrenics. When morphometrically analyzing the density of prohibitinexpressing OLs in diff erent prefrontal white matt...

We propse the one-line search (OLS) method for estimating the three-dimensional (3-D) model of an object from a sequence of images where the object is visible from different points of view. The OLS method estimates each 3-D point through a OLS along the ray defined by the camera center and its two-dimensional (2-D) image projection in one view by maximizing a photo-consistency index built with ...

One of the more surprising recent discoveries in glial biology has been that oligodendrocytes (OLs) originate from very restricted regions of the embryonic neural tube. This was surprising because myelinating OLs are widespread in the mature central nervous system, so there was no reason to suspect that their precursors should be restricted. What we now know about early OL development suggests ...

In regression analysis for deriving scaling laws that occur in various scientific disciplines, usually standard regression methods have been applied, of which ordinary least squares (OLS) is the most popular. In many situations, the assumptions underlying OLS are not fulfilled, and several other approaches have been proposed. However, most techniques address only part of the shortcomings of OLS...

There are three broad classes of models used to address the econometric problems caused by skewness in data commonly encountered in health care applications: (1) transformation to deal with skewness (e.g., OLS on ln(y)); (2) alternative weighting approaches based on exponential conditional models (ECM) and generalized linear model (GLM) approaches; and (3) survival models (Cox proportional haza...

This paper provides some small sample evidence on the appropriateness of ordinary least squares (OLS) and instrumental variable (IV) estimators of the structural equation, and on the appropriate method of performing hypothesis testing in event studies when generated variables are present. In event studies, the number of observations used to estimate the auxiliary equations (and compute the gene...