idiosyncratic component, common component has a larger variance than the idiosyncratic component: [e.
Note that estimates from the log-2SLS model were re-transformed into dollars with a homoskedastic
nonparametric retransformation (Duan 1983).
16 Notes: The null hypothesis for the diagnostic tests are that the residuals do not have serial correlation, are homoskedastic
and are normally distributed.
The distributions are homoskedastic
, and the paired linear correlation coefficients are very close to unity (see Table 3).
Conditional variance and jump-diffusion models outperform simple diffusion and homoskedastic
The OLS assumes that error term is homoskedastic
and not serially correlated that is E [[epsilon]]/X = 0 and E [[epsilon] [epsilon]'/X = [[sigma].
A Cook-Weisberg test for heteroskedasticity indicates that the models are homoskedastic
To obtain normally distributed outcomes at each gestational age with homoskedastic
residual error variance, we first estimated the power transformation of each of the fetal outcomes by modeling their transformed mean as a cubic polynomial in gestational age (in days), using the "boxcox" function from the main package of Venables and Ripley's MASS library (Royston 1995).
It is important to note, however, that 3SLS estimation will provide increased efficiency over 2SLS estimates if the error terms are homoskedastic
but correlated across equations (Cameron and Trivedi, 2005, p.
Model 1 also passes all diagnostic tests, indicating that the residuals are not serially correlated5 (LM test), are normally distributed (Jarque-Bera test), and homoskedastic
Under the additional assumption that asset returns and consumption are jointly log normal and homoskedastic
, the Epstein-Zin Euler equation implies that the risk premium RP on any asset i over the short-term safe asset is
A test of homoskedastic
standard errors is rejected with 90% confidence (p-value = .