Hypothesis testing for geoacoustic environmental models using likelihood ratio

A generalized likelihood ratio test is developed for testing acoustic envir onmental models with an application to parameter inversion using an acousti c propagation code. The signal-to-noise ratio in acoustic measurements prov es to limit the details on geoacoustic environments that can be determined by matched held processing methods. A hypothesis test serves in Monte Carlo simulations as a too! to determine minimal signal levels for the bottom pa rameter inversion. The term ''hierarchy of models'' is used for denoting a sequence of models in which each particular model contains all previous one s. For determining the model order and its parameters, a combined parameter estimation and multiple sequential test is proposed. Given the observed da ta, how many parameters should be included in the model? The last question is important for the order selection in hierarchies of models with an incre asing number of parameters. Multiple sequential hypotheses testing provides a procedure to determine the model order in a statistically justified way. Monte Carlo simulations show the behavior of the test for selecting a mode l order as a function of the signal-to-noise (SNR) ratio. The test is appli ed to broadband data measured using a vertical array near the island of Elb a in the Mediterranean Sea and compared with Akaike's Information Criterion . (C) 1999 Acoustical Society of America. [S0001-4966(99)03502-X].