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In the literature there is limited research on the interaction of language and arithmetic performance of deaf students, although previous studies have demonstrated that many of these students are delayed in both their language acquisition and arithmetic performance. The focus of the first part of this work is a brief review of the literature on acquisition of learning abilities in prelingually deaf children with hearing aids and cochlear implants. Children who experience severe to profound deafness early in their life have a better prognosis for normal literacy development than ever before. In fact, the restoration of the auditory threshold allows children to achieve language and learning abilities like normally hearing children. In the second part we describe our initial experiences in the field. We discuss some preliminary results of an investigation of the longitudinal development of cognitive abilities related to numerical cognition in hearing-impaired children who have had a hearing aid or a cochlear implant at a young age. Specifically, we analyse the development of numerical abilities related to verbal abilities (such as those implied in counting tasks), reading and writing numbers, and analogical numerical abilities (such as those based on quantity recognition as in number comparison and number seriation).

This study synthesizes some preliminary observations made by the clinicians of the Audiology and Phoniatrics Department of Padua-Treviso University on the development of numerical intelligence in deaf children who received cochlear implantation at an early age. This study collected data from clinical observation and standardized instruments, such as Leiter-R and PRCR-Numeri, on a group of 11 preschool deaf children. These data were then compared with those obtained from language performances and audiometric examinations. It is generally recognized that a normal cognitive profile corresponds to scaled scores between 85 and 122. Specifically, the Numerical Intelligence competence is lower in deaf children than in normally hearing children. In particular, the most obvious difference is in the “number comparison” performance, which involves mental operations. In our study, we observed a meaningful connection between Intelligence Quotient (IQ) and the Fluid Reasoning (Fr) score, that is, the ability to solve non-verbal problems independent of previous learning. These results appear to demonstrate a pronounced connectivity of the subcomponents which, taken together, produce visual-spatial functionality.

This research applies a static hedging portfolio method derived from Derman, Ergener, and Kani (1995) (henceforth Derman's SHP method) and a new SHP method with European cash-or-nothing binary options developed by Chung, Shih, and Tsai (2013) to price European continuous double barrier (ECDB) options and the rebates of the ECDB options. Our numerical results indicate that the new SHP method outperforms Derman's SHP method in terms of efficiency and effectiveness under all circumstances.

We use OECD-PIAAC data to estimate the earnings effects of both years of education and of numerical skills. Our identification strategy exploits differential exposure to educational reforms across birth cohorts and countries. We find that education has the strongest earnings effect. A one standard deviation increase in years of education raises earnings by almost 22 percentage points (corresponding to a return to education above 7 percentage points), which compares with a lower percentage points return to an equivalent increase in numerical skills. Our results suggest that the same set of unobservables drives the accumulation of both formal years of education and numeracy skills. OLS estimates underestimate returns to human capital, consistently with the idea that educational reforms favor the human capital acquisition of abler children from disadvantaged parental backgrounds. When we consider numerical skills alone education reforms cannot identify any significant effect of skills on wages, however, when we jointly consider schooling and skills as endogenous factors in a recursive structure we find a significant role for skills in determining wages.

Italian epidemiological data reveal a large discrepancy between the incidence of learning disabilities in mathematics and simple difficulties in mathematics. The incidence of dyscalculia (specific learning disability in mathematics) is about 2%, whereas the incidence of students with difficulties in arithmetic is surprisingly greater, estimated by teachers to be about five students out of 25 (that is, 20%). This unexpectedly high number of students with difficulties invites serious consideration of its cause and remedy. In this chapter, we try to answer to these questions in the light of two educational studies aimed at improving calculation abilities and the outcome of an intervention with three single cases with dyscalculia using the model and the materials of an innovative arithmetical curriculum. The results suggest that for most children, their arithmetic difficulties are simple consequences of their math instruction, which may be remediated by integrating traditional math curricula with information derived from the research on the cognitive arithmetical architecture and its development. There are also implications that even the arithmetical difficulties of dyscalculic children may be improved with special training focused on their specific impairments revealed after a detailed assessment.

Massively parallel desktop computing capabilities now well within the reach of individual academics modify the environment for posterior simulation in fundamental and potentially quite advantageous ways. But to fully exploit these benefits algorithms that conform to parallel computing environments are needed. This paper presents a sequential posterior simulator designed to operate efficiently in this context. The simulator makes fewer analytical and programming demands on investigators, and is faster, more reliable, and more complete than conventional posterior simulators. The paper extends existing sequential Monte Carlo methods and theory to provide a thorough and practical foundation for sequential posterior simulation that is well suited to massively parallel computing environments. It provides detailed recommendations on implementation, yielding an algorithm that requires only code for simulation from the prior and evaluation of prior and data densities and works well in a variety of applications representative of serious empirical work in economics and finance. The algorithm facilitates Bayesian model comparison by producing marginal likelihood approximations of unprecedented accuracy as an incidental by-product, is robust to pathological posterior distributions, and provides estimates of numerical standard error and relative numerical efficiency intrinsically. The paper concludes with an application that illustrates the potential of these simulators for applied Bayesian inference.

Empirical studies show that years of schooling are positively correlated with good health. The implication may go from education to health, from health to education, or from factors that influence both variables. We formalize a model that determines an individual’s demand for knowledge and health based on the causal effects, and study the impacts on the individual’s decisions of policy instruments such as subsidies on medical care, subsidizing schooling, income tax reduction, lump-sum transfers, and improving health at young age. Our results indicate that income redistribution policies may be the best instrument to improve welfare, while a medical care subsidy is the best instrument for longevity. Subsidies to medical care or education would require large imperfections in these markets to be more welfare improving than distributional policies.

Purpose — New methods of measuring user satisfaction in transport services have been proposed and applied in the literature. In this paper, we compare three alternative measures for estimating user satisfaction: the numerical rating, the ordinal rating and the choice.

Approach — We analysed these measures considering their differences and limitations and the models that use these measures as dependent variables. We developed and applied a methodology to build these models. It comprises a preliminary qualitative analysis and a quantitative survey to identify the most relevant attributes of the satisfaction function, and a stated preference survey to obtain information of the alternative satisfaction measures for modelling purpose.

Findings — The ordinal rating may be a better user response to estimate satisfaction than score and choice based on its characteristics. The results obtained in the application reinforced this approach.

Research limitations — It is assumed that choice, score and ordinal valuation depend upon a latent stochastic satisfaction function of the same attributes. Further research is needed to analyse this assumption and how these responses vary according to the context for decision and exogenous factors, including the response scale of ratings.

Practical implications — Gathering alternative satisfaction responses simultaneously from users allowed for the consistency analysis and filtering of data, which greatly benefited the model estimation process.

Originality/value — The paper provides a methodology to estimate user satisfaction models in transit services, which can be applied in other transport services. The conceptual analysis and the application suggest that ordinal ratings are key user responses to uncover the underlying satisfaction function.