A simultaneous sparse approximation problem requests a good approximation of several input signals at once using different linear combinations of the same elementary signals. At the same time, the problem balances the error in approximation against the total number of elementary signals that participate. These elementary signals typically model coherent structures in the input signals, and they...

This paper examines asymptotic expansions for estimation errors expressed explicitly as functions of underlying random variables. Taylor series expansions are obtained from which "rst and second moment approximations are derived. While the expansions are essentially equivalent to the traditional Nagar type, the terms are expressed in a form which enables moment approximations to be obtained in ...

In this paper various methods for the estimation of simultaneous equation models with lagged endogenow variables and List order s&fly correlated errors are discussed. The m.&ods dilfer in tbe number of instrumental variables used. The asymptotic and small sample properties of the various metlmds are compared, and the variables which must be included as insuuments to insure consistent estimates ...