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Strong Statistical Evidence (strong + statistical_evidence)
Selected AbstractsLIVE-BIRTH IN VIPERS (VIPERIDAE) IS A KEY INNOVATION AND ADAPTATION TO GLOBAL COOLING DURING THE CENOZOICEVOLUTION, Issue 9 2009Vincent J. Lynch The identification of adaptations and key innovations has long interested biologists because they confer on organisms the ability to exploit previously unavailable ecological resources and respond to novel selective pressures. Although it can be extremely difficult to test for the effects of a character on the rate of lineage diversification, the convergent evolution of a character in multiple lineages provides an excellent opportunity to test for the effect of that character on lineage diversification. Here, I examine the effect of parity mode on the diversification of vipers, which have independently evolved viviparity in at least 13 lineages. I find strong statistical evidence that viviparous species diversify at a greater rate than oviparous species and correlate major decreases in the diversification rate of oviparous species with periods of global cooling, such as the Oligocene. These results suggest that the evolution of viviparity buffered live-bearing species against the negative effects of global climate change during the Cenozoic, and was a key innovation in the evolution and diversification of live-bearing vipers. [source] Fiscal Coordination and Financial Dependence of State Governments in MexicoPUBLIC BUDGETING AND FINANCE, Issue 3 2010JORGE IBARRA-SALAZAR This paper presents evidence of the effects on subnational financial dependence of the intergovernmental fiscal agreement implemented in 1980. In contrast with a previous study that uses annual time series national data, we use a panel of annual time series (1975,1995) of 31 Mexican states. We propose and estimate three different empirical models using the fixed effects panel data approach. In concordance with previous literature, we find strong statistical evidence that the implementation of the agreement increased financial dependence. The main contribution of this paper is to distinguish the effect of the 1980 fiscal arrangement on every state's degree of financial dependence. [source] Recursive Modeling of Nonlinear Dynamics in UK Stock ReturnsTHE MANCHESTER SCHOOL, Issue 4 2003Massimo Guidolin This paper presents results from recursive modeling of nonlinear dynamics in UK stock returns. A specification search suggests a two-state model and we demonstrate the ability of this model to capture time-varying volatility, skew and kurtosis in UK stock returns. An out-of-sample forecasting experiment confirms the strong statistical evidence of nonlinearity and shows that accounting for regimes leads to improved forecasting performance. [source] The use of long PCR to confirm three common alleles at the CYP2A6 locus and the relationship between genotype and smoking habitANNALS OF HUMAN GENETICS, Issue 5 2000D. F. GU Long PCR followed by nested PCR has previously been used to determine CYP2A6 160H alleles, but the method proved unreliable. We have optimized this approach in a DNA bank of 1032 subjects (age range 59,74 years) to give reliable results, yielding indirect molecular evidence and very strong statistical evidence of hitherto unrecognized common alleles (designated O) recalcitrant to the long PCR. Coding three alleles (160L, 160H and O) and an approach to association analysis originally developed to deal with null alleles implicit in ABO blood group phenotyping, the contribution of 160H (functionally null) to reduced smoking habit has been clearly measured for the first time, unconfounded by alleles null to the long PCR. The most significant findings (p < 0.01) are that the possession of a 160H allele, compared with not possessing a 160H allele, is associated with a mean age of starting regular smoking 3 years later (95% CIą1.93 years, average start age 20,21 years rather than 17,18 years); and that the average likelihood of quitting smoking at any time is 1.75 fold (95% CI. 1.17,2.61) for those possessing an 160H allele compared with those who have no 160H allele. This suggests that a smoking subject with a genotype predicted to confer 50% of the ability to eliminate nicotine via the CYP2A6 pathway has almost twice the likelihood of quitting smoking. [source] |