Male passerine bird song is a classic example of a sexually selected display. Theory predicts that such displays should be costly, but there are few empirical data on the potential costs of bird song. We measured the rate of oxygen consumption by male pied flycatchers, Ficedula hypoleuca,...

Many authors suggest that conditions originally presented by Howe (1955) and later by Jöreskog (1979) are sufficient to identify confirmatory factor analysis models. In this note we show that these are sufficient conditions for unique factor loadings under rotation but they are not sufficient...

Assessing overall fit is a topic of keen interest to structural equation modelers, yet measuring goodness of fit has been hampered by several factors. First, the assumptions that underlie the chi-square tests of model fit often are violated. Second, many fit measures (e.g., Bentler and Bonett's...

Bayes factors (BFs) play an important role in comparing the fit of statistical models. However, computational limitations or lack of an appropriate prior sometimes prevent researchers from using exact BFs. Instead, it is approximated, often using the Bayesian Information Criterion (BIC) or a...

Least absolute deviation (LAD) is a well-known criterion to fit statistical models, but little is known about LAD estimation in structural equation modeling (SEM). To address this gap, the authors use the LAD criterion in SEM by minimizing the sum of the absolute deviations between the observed...

In this article, the authors examine the most common type of improper solutions: zero or negative error variances. They address the causes of, consequences of, and strategies to handle these issues. Several hypotheses are evaluated using Monte Carlo simulation models, including two structural...

This article extends Bollen's two-stage least squares (2SLS) estimator to estimate confirmatory higher-order factor analysis models. This includes estimation of the higher-order and lower-order factor loadings and their intercepts. This 2SLS estimator does not require that the observed variables...

This article is an empirical evaluation of the choice of fixed cutoff points in assessing the root mean square error of approximation (RMSEA) test statistic as a measure of goodness-of-fit in Structural Equation Models. Using simulation data, the authors first examine whether there is any...