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Below results based on the criteria 'LISREL'
Total number of records returned: 3
The Robustness of Normal-theory LISREL Models: Tests Using a New Optimizer, the Bootstrap, and Sampling Experiments, with Applications
Mebane, Walter R.
Wells, Martin T.
linear structural relations
Asymptotic results from theoretical statistics show that the linear structural relations (LISREL) covariance structure model is robust to many kinds of departures from multivariate normality in the observed data. But close examination of the statistical theory suggests that the kinds of hypotheses about alternative models that are most often of interest in political science research are not covered by the nice robustness results. The typical size of political science data samples also raises questions about the applicability of the asymptotic normal theory. We present results from a Monte Carlo sampling experiment and from analysis of two real data sets both to illustrate the robustness results and to demonstrate how it is unwise to rely on them in substantive political science research. We propose new methods using the bootstrap to assess more accurately the distributions of parameter estimates and test statistics for the LISREL model. To implement the bootstrap we use optimization software two of us have developed, incorporating the quasi-Newton BFGS method in an evolutionary programming algorithm. We describe methods for drawing inferences about LISREL models that are much more reliable than the asymptotic normal-theory techniques. The methods we propose are implemented using the new software we have developed. Our bootstrap and optimization methods allow model assessment and model selection to use well understood statistical principles such as classical hypothesis testing.
Bootstrap Methods for Non-nested Hypothesis Tests
Mebane, Walter R.
Endogenous Switching Regression
Cox (1961; 1962) proposed a fairly general method that can be used to construct powerful tests of alternative hypotheses from separate statistical families. We prove that non-parametric bootstrap methods can produce consistent and second-order correct approximations to the distribution of the Cox statistic for non-nested LISREL-style covariance structure models. We use the method to investigate a question about the specification of a LISREL model used by Kinder, Adams and Gronke (1989). In a second application---a pair of non-nested endogenous switching regression models with tobit-style censoring, applied to real data---we illustrate how bootstrap calibration can be used to correct the size of the test when the test distribution is being estimated by Monte Carlo simulation due to concern about nonregularity.
The Reciprocal Relationship Between State Defense Interest and Committee Representation in Congress
Pooled Time Series
Does prior representation of a state on a Congressional defense committee lead to higher levels of per capita defense contract, or do higher levels of prior per capita contract awards to a state increase its probability of being represented on a defense committee? To solve this puzzle, we estimate a cross-lagged three-equation model on data from all 50 states from 1963 to 1989 using maximum likelihood within LISREL. We find a substantial reciprocal but non-confounding relationship between representation and the allocation of benefits for the House, but not for the Senate. Thus, for the House, this more appropriate model of distributive politics in Congress supports both the committee-induced benefits hypothesis and the recruitment hypothesis. Further, the paper elaborates on how this reciprocal relationship plays out over time.