Bu çalışmada C20 ve C25 sınıfı betonların, beton santralı çıkışı ile şantiye şartlarındaki kalite kontrolünün analizi yapılmıştır. amaç doğrultusunda santralde şantiyede taze sıcaklığı, çökme (slump) ölçülmüş basınç dayanımı için küp numuneler alınmıştır. 7 28 günlük her yaş 3 adet, 6 adet 150 mm numune alınmıştır.İşlenebilirliği belirlemede kullanılan testinin şantiyedeki değeri, santraldan da...

This paper is concerned with the analysis of zero-inflated count data when time of exposure varies. It proposes a new zero-inflated count data model that is based on two homogeneous Poisson processes and accounts for exposure time in a theory consistent way. The new model is used in an application to the effect of insurance generosity on the number of absent days. JEL Classification: J29, C25

A finite probability mixture model is combined with a contingent valuation model to analyze the existence of differential market segments in a hypothetical market. The approach has at least two principle benefits. First, the model is capable of identifying market segments within the hypothetical market. Second, the model can be used to estimate WTP/WTA within each segment. The model is illustra...

This paper estimates demand for Internet portals using a clickstream data panel of 2654 users. It shows that familiar econometric methodologies used to study grocery store scanner data can be applied to analyze advertising-supported Internet markets using clickstream data. In particular, it applies the methodology of Guadagni and Little (1983) to better understand households’ Internet portal ch...

This paper is concerned with a semiparametric Bayesian framework for estimating quantile treatment effects. A general and flexible model is specified using a generalization of the Pólya urn scheme. An exact Bayesian analysis is carried out by Markov chain Monte Carlo simulation methods. The proposed techniques are illustrated by estimating the effect of participation in the 401(k) retirement pr...

We consider a bivariate Poisson model that is based on the lognormal heterogeneity model. Two recent applications have used this model. We suggest that the correlation estimated in their model frameworks is an ambiguous measure of the correlation of the variables of interest, and may substantially overstate it. We conclude with a detailed application of the proposed method using the data employ...

Fusarium culmorum F1 was found to produce and secrete into the culture medium several of 5-n-alkylresorcinols. The amount of resorcinolic lipids was 5.3 microg/g and 0.9 microg/l in mycelium and in post-culture liquid, respectively. First of all F. culmorum F1 produces saturated homologues with C15 to C25 side chains. The extract from the medium contained only homologues with shorter carbon cha...