121 research outputs found
We Know What You Choose! External Validity of Discrete Choice Models
For over the last thirty years the multinomial logit model has been the standard in choice modeling. Development in econometrics and computational algorithms has led to the increasing tendency to opt for more flexible models able to depict more realistically choice behavior. This study compares three discrete choice models, the standard multinomial logit, the error components logit, and the random parameters logit. Data were obtained from two choice experiments conducted to investigate consumersâ preferences for fresh pears receiving several postharvest treatments. Model comparisons consisted of in-sample and holdout sample evaluations. Results show that product characteristics hence, datasets, influence model performance. We also found that the multinomial logit model outperformed in at least one of three evaluations in both datasets. Overall, findings signal the need for further studies controlling for context and dataset to have more conclusive cues for discrete choice models capabilities.discrete choice models, validation, holdout sample
Comparison of Stated Choice and In-store Experimental Methods in Predicting Actual Market Behavior for Freshwater Prawn (Macrobrachium rosenbergii) Consumers
The stated choice (SC) and actual revealed pricing/purchase experimental methods were compared for their ability to predict purchasing behavior and willingness-to-pay for freshwater prawns. SC hypothetical bias may be a consequence of difficulties in controlling factors affecting real world situations, small sample sizes and confusion related to the new product.choice experiment, grocery store experiment, new product, purchasing behavior, Consumer/Household Economics,
A Comparison Of Choice Experiments And Actual Grocery Store Behavior: An Empirical Application To Seafood Products
In this paper we compare results from an in-store field experiment and a mail survey choice experiment (CE) to investigate CEâs capacity in predicting grocery store market share. For the comparison, we used three seafood products: freshwater prawns, marine shrimp, and lobster. CE estimates were obtained via four econometric models: the conditional logit, the random parameter logit, the heteroskedastic extreme value, and the multinomial probit. We found that the level of control in the grocery store experiment and the choice of econometric model influenced the capacity of CE to predict grocery store market shares.choice experiment, grocery store, hypothetical bias, Food Consumption/Nutrition/Food Safety, Marketing, C35, Q13,
Consumer Preferences for Foods with Clean Labels and New Food Technologies
Foods with âclean labels,â that is, foods with few ingredients, may mitigate the stigma from the lack of healthfulness in processed food products. However, with conventional technologies, clean labels are difficult to achieve. We conducted a survey, including choice experiment scenarios, in which half of the respondents were presented scenarios to purchase a shelfâstable ready meal with a clean label/fewer ingredients, and the other half were presented scenarios including the clean label/fewer ingredients and a new technology that al-lows for processed foods to be produced with fewer ingredients. In general, respondents were willing to pay a price premium for the clean label and the new food technology used. However, such preferences were heterogeneous. In the version of the survey that did not include the type of technology, the classes were âclean label incredulous, moderate believers in clean labels, and âstrong believers in clean labels.â In the survey version including the type of technology, the classes were âclean label indifferent and technology takers, moderate believers in clean labels and technology indifferent,â and âstrong believers in clean labels and technology indifferent.â Our findings underscore the importance of providing consumers with information about a new technology and the resulting benefits to reduce perceived risks and increase consumer acceptance
Perceptions of Precision Agriculture Technologies in the U.S. Fresh Apple Industry
Advances in precision agriculture technologies provide opportunities to improve the efïŹciency of agricultural production systems, especially for high-value specialty crops such as fresh apples (Malus domestica). We distributed an online survey to apple growers in Washington, New York, and Michigan to elicit stakeholder perceptions of precision agriculture technologies. Findings from this study demonstrated that growers are willing to adopt precision agriculture technologies when they receive results from applied research projects and are engaged with active extension programs. The availability of customized services and purchasing and rental options may minimize the effects of the economies of size that create barriers to adopting increasing access to technologies. Finally, respondents deemed collaborative efforts between industry and academic institutions crucial for adapting the innovation to better address the needs of growers
From planning to execution to the future: An overview of a concerted effort to enhance biological control in apple, pear, and walnut orchards in the western U.S.
We embarked on a large project designed to help enhance biological control in apple, pear and walnut orchards in the western U.S., where management programs were in the midst of a transition from older organo-phosphate insecticides to mating disruption and newer reduced-risk insecticides. A âpesticide replacement therapyâ approach resulted in unstable management programs with unpredictable outbreaks of spider mites and aphids. Our project was designed to provide growers and pest managers with information on the effects of newer pesticide chemistries on a suite of representative natural enemies in both the laboratory and field, potential of new monitoring tools using herbivore-induced plant volatiles and floral volatiles, phenology of the key natural enemy species, economic consequences of using an enhanced biological control program, and value of an outreach program to get project outcomes into the hands of decision-makers. We present an overview of both the successes and failures of the project and of new projects that have spun off from this project to further enhance biological control in our systems in the near future
Willingness to Pay for Blueberries: Sensory Attributes, Fruit Quality Traits, and Consumersâ Characteristics
Understanding consumersâ preferences for fruit quality attributes is key to informing breeding efforts, meeting consumer preferences, and promoting increased market demand. The objective of this study was to assess the effect of fruit quality traits and hedonic sensory evaluation on consumersâ willingness to pay (WTP) for a selection of fresh northern and southern highbush blueberry cultivars. The WTP was elicited by using a double-bounded contingent valuation conducted in conjunction with a consumer sensory test. Two types of models were estimated using either sensory evaluations (i.e., consumer preference and consumer intensity) or instrumental measurement data (i.e., measures of soluble solids, titratable acidity, sugars, acids, and firmness) as explanatory variables to model WTP. Results using sensory evaluations indicated that flavor liking, flavor intensity, and sweetness intensity are key factors that influence consumersâ acceptance and WTP for blueberries. A regression analysis using instrumental measurements indicated that measures related to sweetness and acidity traits are important factors that determine WTP. Higher WTP was associated with higher total sugar content across different levels of total organic acid. The WTP increases with organic acid content, because this is needed for enhanced flavor; however, WTP declines at high concentrations of organic acid. Except for extreme values of firmness, the WTP increased as measures of fruit firmness increased, indicating a consumer preference for firmer blueberries. Overall, the results provided new insights into the relationships between consumer preference and WTP and fruit quality benchmarks to select for improved quality
There and back again: historical perspective and future directions for Vaccinium breeding and research studies
The genus Vaccinium L. (Ericaceae) contains a wide diversity of culturally and economically important berry crop species. Consumer demand and scientific research in blueberry (Vaccinium spp.) and cranberry (Vaccinium macrocarpon) have increased worldwide over the crops' relatively short domestication history (~100 years). Other species, including bilberry (Vaccinium myrtillus), lingonberry (Vaccinium vitis-idaea), and ohelo berry (Vaccinium reticulatum) are largely still harvested from the wild but with crop improvement efforts underway. Here, we present a review article on these Vaccinium berry crops on topics that span taxonomy to genetics and genomics to breeding. We highlight the accomplishments made thus far for each of these crops, along their journey from the wild, and propose research areas and questions that will require investments by the community over the coming decades to guide future crop improvement efforts. New tools and resources are needed to underpin the development of superior cultivars that are not only more resilient to various environmental stresses and higher yielding, but also produce fruit that continue to meet a variety of consumer preferences, including fruit quality and health related trait
Mapping density, diversity and species-richness of the Amazon tree flora
Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution
Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates
Aim: To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis).
Time period: Tree-inventory plots established between 1934 and 2019.
Major taxa studied: Trees with a diameter at breast height (DBH) â„â9.55âcm.
Location: Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield.
Methods: We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes.
Results: Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests.
Main conclusions: The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types
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