21. Durbin's h-test ( see below ) or likelihood ratio tests , that are valid in large samples, should be used. 22. The tenability of each model can be tested statistically by using a likelihood ratio test or other indices of fit. 23. Many standard tests for divergence and convergence, most notably including the ratio test and the root test, demonstrate absolute convergence. 24. It may be cumbersome to try to apply the ratio test to find the radius of convergence of this series. 25. As seen in the previous example, the ratio test may be inconclusive when the limit of the ratio is 1. 26. With series, the purpose of the ratio test is to determine convergence ( or divergence ) of a given series. 27. In particular, the likelihood-ratio test is valid only for nested models, whereas AIC ( and AICc ) has no such restriction. 28. One main test that is performed on amniotic fluid is the L / S ratio test ( lecithin / sphigomyelin ). 29. Further, it can be used in a hypothesis test for whether evolutionary rates are constant ( by using likelihood ratio tests ). 30. This illustrates that when " L " = 1, the series may converge or diverge and hence the original ratio test is inconclusive.
