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Sensory evaluations to determine the shelf life of food products are routinely conducted in food experimentation as a part of each product development program, whether it includes a new product, product improvement or a change in type or specification of an ingredient. In such experiments, trained panelists are asked to judge food attributes by reference to a scale of numbers. The “failure time” associated with a product unit under test is usually defined as the time required to reach a cut‐off point previously defined by the food company. Important issues associated with the planning and execution of this kind of testing are total sampling size, frequency of sample withdrawals, panel design, and statistical analysis of the panel data, to list a few. Different approaches have been proposed for the analysis of this kind of data. In particular, Freitas et al. proposed an alternative model based on a dichotomization of the score data and a Weibull as the underlying distribution for the time to failure. Also, through a simulation study, the bias and mean square error of the estimates obtained for percentiles and fraction defectives were evaluated. These quantities were used to estimate the shelf life. The simulation study used only the same sample plan implemented in the real situation. This paper focuses on the planning issues associated with these experiments. Sample plans are contrasted and compared in a simulation study, through the use of the approach proposed by Freitas et al.. The simulation results showed that, in general, one can get results much more precise and with smaller bias with a shorter follow‐up time, allocating more panelists to each evaluation time.

A progressive hybrid censoring scheme (PHCS) becomes impractical for ensuring dependable outcomes when there is a low likelihood of encountering a small number of failures prior to the predetermined terminal time T. The generalized progressive hybrid censoring scheme (GPHCS) efficiently addresses to overcome the limitation of the PHCS.

In this article, estimation of model parameter, survival and hazard rate of the Unit-Lindley distribution (ULD), when sample comes from the GPHCS, have been taken into account. The maximum likelihood estimator has been derived using Newton–Raphson iterative procedures. Approximate confidence intervals of the model parameter and their arbitrary functions are established by the Fisher information matrix. Bayesian estimation procedures have been derived using Metropolis–Hastings algorithm under squared error loss function. Convergence of Markov chain Monte Carlo (MCMC) samples has been examined. Various optimality criteria have been considered. An extensive Monte Carlo simulation analysis has been shown to compare and validating of the proposed estimation techniques.

The Bayesian MCMC approach to estimate the model parameters and reliability characteristics of the generalized progressive hybrid censored data of ULD is recommended. The authors anticipate that health data analysts and reliability professionals will get benefit from the findings and approaches presented in this study.

The ULD has a broad range of practical utility, making it a problem to estimate the model parameters as well as reliability characteristics and the significance of the GPHCS also encourage the authors to consider the present estimation problem because it has not previously been discussed in the literature.

In this chapter we perform a Monte Carlo simulation study of the errors-in-variables model examined in Ramsey, Gallegati, Gallegati, and Semmler (2010) by using a wavelet multiresolution approximation approach. Differently from previous studies applying wavelets to errors-in-variables problem, we use a sequence of multiresolution approximations of the variable measured with error ranging from finer to coarser scales. Our results indicate that multiscale approximations to the variable observed with error based on the coarser scales provide an unbiased asymptotically efficient estimator that also possess good finite sample properties.

This paper aims to propose an approach based on physical model integration for surface and cloud albedo computation using an approximate form of the atmospheric radiative transfer equation and sun-pixel-satellite.

The data used in this study are global irradiance collected from for various sites in Algeria, and data were obtained from the processing of the high-resolution visible images taken by the Meteosat Second Generation satellite in 2010.

The results suggest that the standard deviation obtained with this method is similar to that obtained with current estimation methods. The hourly and daily correlation coefficients range between 0.95 and 0.97 and between 0.97 and 0.99, respectively. The hourly and daily mean bias errors range between −0.2 and +1.2 per cent and between −0.2 and +1.4 per cent, respectively. The hourly and daily root mean square errors range between 10 and 17 per cent and between 4 and 8 per cent, respectively.

This paper developed a new estimating method that derives the hourly global horizontal solar irradiation at a ground level from geostationary satellite data under local climate conditions.

Unrealistic optimism is a well‐documented psychological phenomenon. The purpose of this paper is to discuss the meaning of being “unrealistically optimistic”. This bias has important implications in many economic and managerial contexts and the authors present evidence of it. Although the policy and welfare implications of such a widespread phenomenon are vast, they have been largely neglected by policy makers. The authors propose conservative paternalistic measures.

Critical review of existing literature on Unrealistic Optimism. Analyses of some relevant variables of the mortgage and corporate credit markets in Portugal and Spain.

The authors point to evidence and argue that Unrealistic Optimism may well have been at play in the recent behaviour of mortgage and corporate credit markets in Portugal and Spain.

Because ignoring such biases may simply lead borrowers and financial institutions down a real road to ruin, it is important to discuss paternalistic policies that may mitigate them. The paper therefore presents a conservative approach to paternalistic measures that policy makers should consider adopting.

The paper shows the link between irrational behaviour and mortgage and corporate credit markets in Portugal and Spain and suggests paternalistic policies that should be encouraged.

In this paper, the authors design accelerated life test and provide its application in the field of accelerated life test. The authors use maximum likelihood estimation method as a parameter estimation method.

In this paper we design accelerated life test and provide its application in the field of accelerated life test. The authors use maximum likelihood estimation method as a parameter estimation method.

In this study, the authors design accelerated life test under Type-I censoring when the lifetime of test items follows PID and also provides its application in the field of warranty policy. The following conclusion is made on the basis of this study. (1) An inverse relationship is shown between the shape parameter with the expected total cost and expected cycle time, while the shape parameter directly relates to the expected cost rate (see Table 5). (2) A direct relationship is shown between the scale parameter with the expected total cost and expected time cycle, while the inverse relationship is shown with the expected cost rate (see Table 5). (3) An inverse relationship is shown between the replacement age and the expected cost rate, while there are direct relationships between expected total cost and expected time cycle (see Table 5).

This paper is neither published or neither accepted anywhere.

This study examines the accuracy and bias of profit forecasts disclosed in prospectuses by New Zealand companies for initial public offerings during the period 1987 to 1994. The results show that profit forecasts in this period are, on average, more accurate titan those disclosed prior to 1987, which were examined in prior studies. However, the results reject the null hypothesis that profit forecasts are accurate. In examining forecast bias, the evidence shows that the forecasts are, on average, somewhat pessimistic, but not sufficiently to reject the hypothesis that profit forecasts are unbiased. Tests of the determinants of error show that larger companies make more accurate forecasts, and forecasts made in the year 1987 are less accurate than in other years. Tests of the determinants of bias show that forecasts made in 1987 are also more optimistic, and that companies with longer trading histories and pessimistic forecasts make less biased forecasts. Forecast period and industry type are not significantly related to error or bias.

Food poisoning attributable to the home generates a large disease burden, yet is an unregulated and largely unobserved domain. Investigating food safety awareness and routine practices is fraught with difficulties. The purpose of this paper is to develop and apply a new survey tool to elicit awareness of food hazards. Data generated by the approach are analysed to investigate the impact of oberservable heterogeneity on food safety awareness.

The authors develop a novel Watch-and-Click survey tool to assess the level of awareness of a set of hazardous food safety behaviours in the domestic kitchen. Participants respond to video footage stimulus, in which food hazards occur, via mouse clicks/screen taps. This real-time response data is analysed via estimation of count and logit models to investigate how hazard identification patterns vary over observable characteristics.

User feedback regarding the Watch-and-Click tool approach is extremely positive. Substantive results include significantly higher hazard awareness among the under 60s. People who thought they knew more than the average person did indeed score higher but people with food safety training/experience did not. Vegetarians were less likely to identify four of the five cross-contamination hazards they observed.

A new and engaging survey tool to elicit hazard awareness with real-time scores and feedback is developed, with high levels of user engagement and stakeholder interest. The approach may be applied to elicit hazard awareness in a wide range of contexts including education, training and research.

The purpose of this paper is to test the direct effect of B2B sellers' skills on relative and absolute sales performance.

Based on a questionnaire survey and deductive approach. A total of 236 useable questionnaires out of 315 are returned, generating a response rate of 74.9%.

Only one out of twelve hypothesized relationships in the research model of the direct effect of B2B sellers' skills on relative and absolute sales performance turned out to be significant.

Indicate that the researchers’ current understanding of the effect of sales performance indicators on sales performance, based on B2B sellers' skills, is narrow and simplistic.

Results indicate that there are skills other than the tested ones (i.e. interpersonal, adaptiveness and selling-related knowledge), that can have direct effects on B2B sellers' relative and absolute sales performance.

Sheds light on the ambiguous direct effect of B2B sellers' skills on sales performance and the almost non-existent direct effect on B2B sellers' relative and absolute sales performance.

This study aims to examine the role of salespeople’s skills in relative and absolute SP in business-to-business (B2B) settings of services firms. This conceptual logic reported in meta-analytical works, that salespeople’s skills relate directly to their sales performance (SP), is questioned.

his research relies on existing theory and previous studies on SP drivers and SP measures. The literature identifies a set of common denominators on the role of salespeople’s skills regarding their SP, all of which are tested in this study. Based on a deductive approach and questionnaire survey, 732 service firms in Norway were targeted. A total of 389 questionnaires were returned, generating a response rate of 53.1%.

A total of 10 out of 12 hypothesized relationships in the research model dealing with the relationship between SP drivers and SP turn out to be non-significant. The hypothesized relationship in the research model between relative and absolute SP is also supported.

The results reported in this study, based on a large sample of service firms, empirically confirm that the direct effect is generally overestimated. Empirical evidence is provided that sheds additional light on the role of salespeople’s skills in relative and absolute SP in B2B settings of services firms.

This study offers meaningful and relevant insights into the monitoring of SP drivers to practitioners in B2B sales settings of services firms. Salespeople need to learn about gathering knowledge in training programs about each customer and their specific situation. Firms should strive to recruit salespeople who possess the appropriate skills, taking into consideration their customers and specific situations related to them, such as experiences from competitors. Salespeople may be organized around similar customers and similar customer situations, rather than geographical assignments.

Overall, this research contributes insights into the role played by salespeople’s skills in relative and absolute SP in B2B settings of services firms. In particular, the research contributes additional insights into the non-existent role of interpersonal presentation and communication skills, adaptiveness of sales approach and sales behavior skills and product/technology-related knowledge skills in salespeople’s relative and absolute SP in B2B settings of services firms.