Research On The Relation Between Capital Structure And Performance Of Public Company

Panel data is the several cross-sectional sample data intercepted from the time-series.It is the combination of the time-series and sectional sets.As a kind of economics model,the panel data can be viewed as the two-way design of co-variables.In recent 20 years ,the panel data model has achieved significant progress in econometric theory.In economic analysis,the panel data allow a researcher to analyze a number of important question that cannot be addressed using time-series or cross-sectional sets,which denotes its practical value.These are the primary contents of this paper:First, this paper introduces the basic theory of the company's performance and interest structure,then give the conjecture of the relation between them.Secend, this paper introduces the setting and estimation of general panel data model,aslo introduces how to judge fixxed model and random model.Then use medical public company 's data,and give the results.Third, Because some sample is stride trade or stride area,so it may exist heteroskedasiticity ,this paper especially study the heteroskedasticity of panel data .Using the spedtral decomposition of covariance matrix. We give the likelihood function expression under various possible heteroskedasticities. Then we use the MLE method to estimate paraneters.At last we use the likelihood ratio test method to specify the model.Using the spectral decomposition of covariance matrix .we convert the GLSmethod to OLS method to estimate the parameters. Then we choose some company as the sample ,and receive some useful resultsFourth, In order to all-around research the question,we research the listed company.