Understanding and quantifying the determinants of the number of sectors or firms exporting in a given country is of relevance for the assessment of trade policies. Estimation of models for the number of sectors, however, poses a challenge because the dependent variable has both a lower and upper bound, implying that the partial effects of the explanatory variables on the conditional mean of the...

Low-Wage Employment in Portugal: A Mixed Logit Approach In this paper, we examine the determinants of low-wage employment in Portugal. For this purpose, we use a data file of the European Community Household Panel (ECHP) for the years 1998 and 1999. In order to take into account unobserved heterogeneity in the data, a random-parameter logit model is used to analyse the probability of a worker r...

This paper identifies pivotal factors behind individual decision-making in the transition from high school to post-secondary education in the Netherlands. We apply a multinomial logit framework to individual data on post-secondary education choices. Specifically, our modeling approach accommodates two types of effects that have not received ample attention in the literature. First, we include i...

Regioselective opening of ring E of solasodine under various conditions afforded (25R)-22,26-epiminocholesta-5,22(N)-diene-3beta,16beta-diyl diacetate (previously known as 3,16-diacetyl pseudosolasodine B), C(31)H(47)NO(4), or (22S,25R)-16beta-hydroxy-22,26-epiminocholesta-5-en-3beta-yl acetate (a derivative of the naturally occurring alkaloid oblonginine), C(29)H(47)NO(3). In both cases, the r...

In this paper we examine the demand for education among rural Black households in South Africa using nationally representative data from the 1990s. In particular our study focuses on factors affecting schooling decisions at the household level. Our estimation results reveal strong evidence of a sibling synergy effect, in that the presence of other school-age children in a household makes it mor...

Multi proxy records relating to climate and vegetation have been obtained for a core spanning the last 40 kyr from the Heqing Lake Basin (26 N, 100 E; 2200 m asl.), Yunnan Province of southwestern China. Compound-specific carbon isotope records for the vascular plant leaf wax hydrocarbons, the C23–C33 n-alkanes, and for the algal hydrocarbons, the C23 and C25 n-alkenes and a C30 cyclobotryococc...

The paper focuses on the effects of three different internal bank ratings – Risk-, Propertyand Creditworthiness-Rating – on the loan maturity. We use a sample of about 5,000 loans given to sole proprietors and corporate borrowers by two German banks from January 2003 till July 2005. The estimation results for corporate borrowers are consistent with Diamond’s (1991) predictions of non-monotonic ...

In this paper we develop a dynamic model for integer counts to capture the discreteness of price changes for financial transaction prices. Our model rests on an autoregressive multinomial component for the direction of the price change and a dynamic count data component for the size of the price changes. Since the model is capable of capturing a wide range of discrete price movements it is part...

Individual data from a continuous distribution are often partitioned into a collection of intervals defined by either fixed interval limits or sample quantiles. In this study, we derive asymptotic distribution of interval statistics for both cases, allowing multiple sample statistics for each interval. Under fixed intervals, the covariance matrix is singular. We identify a computationally simpl...

Terpenoids are the most diverse and abundant natural products among which sesterterpenes account for less than 2%, with very few reports on their biosynthesis. Ophiobolins are tricyclic 5-8-5 ring sesterterpenes with potential pharmaceutical application. Aspergillus ustus 094102 from mangrove rizhosphere produces ophiobolin and other terpenes. We obtained five gene cluster knockout mutants, wit...