1,138 research outputs found

    An efficient approach to understanding and predicting the effects of multiple task characteristics on performance

    Get PDF
    In ergonomics there is often a need to identify and predict the separate effects of multiple factors on performance. A cost-effective fractional factorial approach to understanding the relationship between task characteristics and task performance is presented. The method has been shown to provide sufficient independent variability to reveal and predict the effects of task characteristics on performance in two domains. The five steps outlined are: selection of performance measure, task characteristic identification, task design for user trials, data collection, regression model development and task characteristic analysis. The approach can be used for furthering knowledge of task performance, theoretical understanding, experimental control and prediction of task performance

    Children's construction task performance and spatial ability: controlling task complexity and predicting mathematics performance.

    Get PDF
    This paper presents a methodology to control construction task complexity and examined the relationships between construction performance and spatial and mathematical abilities in children. The study included three groups of children (N = 96); ages 7-8, 10-11, and 13-14 years. Each group constructed seven pre-specified objects. The study replicated and extended previous findings that indicated that the extent of component symmetry and variety, and the number of components for each object and available for selection, significantly predicted construction task difficulty. Results showed that this methodology is a valid and reliable technique for assessing and predicting construction play task difficulty. Furthermore, construction play performance predicted mathematical attainment independently of spatial ability

    Informal learning in the workplace: Approaches to learning and perceptions of the context

    Get PDF
    Questionnaires have been devised to investigate informal learning in the workplace based on an analogy with approaches to studying in higher education. This chapter focuses attention on issues of theory by critically evaluating different models of the relationship between employees’ approaches to workplace learning and their perceptions of the workplace context. In addition, this chapter focuses attention on issues of method by critically evaluating two particular instruments that have been devised in order to measure employees’ approaches to workplace learning and their perceptions of the workplace context. We use data from an online survey in which the Approaches to Work Questionnaire and the Workplace Climate Questionnaire were administered to employees who were taking courses by distance learning with the UK Open University. Factor analyses confirmed that both questionnaires measured three distinct scales. Canonical correlation analysis showed that the employees’ scores on the two instruments shared 43% of their variance. Path analysis found evidence that variations in approaches to learning lead to variations in perceptions of the workplace climate but not for the converse relationship

    Validity of a Protocol for Adult Self-Report of Dyslexia and Related Difficulties

    Get PDF
    Background: There is an increased prevalence of reading and related difficulties in children of dyslexic parents. In order to understand the causes of these difficulties, it is important to quantify the risk factors passed from parents to their offspring. Method: 417 adults completed a protocol comprising a 15-item questionnaire rating reading and related skills and a scale assessing ADHD symptoms; 344 completed reading, nonword reading and spelling tests. Results: A confirmatory factor analysis with four factors (Reading, Word Finding, Attention and Hyperactivity) provided a reasonable fit to the data. The Reading Factor showed robust correlations with measured literacy skills. Adults who reported as dyslexic, or rated their reading difficulties as more severe, gained lower scores on objective measures of literacy skills. Although the sensitivity of the new scale was acceptable, it tended to miss some cases of low literacy. Conclusions: Self-report scales of reading and of attention difficulties are useful for identifying adults with reading and attention difficulties which may confer risks on their children of related problems. It is important for research following children at family risk of dyslexia to be aware of these effects

    Who Believes in the Giant Skeleton Myth? An Examination of Individual Difference Correlates

    Get PDF
    This study examined individual difference correlates of belief in a narrative about the discovery of giant skeletal remains that contravenes mainstream scientific explanations. A total of 364 participants from Central Europe completed a survey that asked them to rate their agreement with a short excerpt describing the giant skeleton myth. Participants also completed measures of the Big Five personality factors, New Age orientation, anti-scientific attitudes, superstitious beliefs, and religiosity. Results showed that women, as compared with men, and respondents with lower educational qualifications were significantly more likely to believe in the giant skeleton myth, although effect sizes were small. Correlational analysis showed that stronger belief in the giant skeleton myth was significantly associated with greater anti-scientific attitudes, stronger New Age orientation, greater religiosity, stronger superstitious beliefs, lower Openness to Experience scores, and higher Neuroticism scores. However, a multiple regression showed that the only significant predictors of belief in myth were Openness, New Age orientation, and anti-scientific attitudes. These results are discussed in relation to the potential negative consequences of belief in myths

    The relative importance of comprehensive performance measurement systems and financial performance measures on employees’ perceptions of informational fairness

    Get PDF
    Research on how performance measurement systems affect employees' perceptions of workplace fairness is important. As organizations often rely on their performance measurement systems to communicate information to their employees, it is useful to ascertain if and how the developments of performance measurement systems that are far more comprehensive than traditional financial systems affect employees' perceptions of informational fairness through the information communicated to employees. Informational fairness refers to employees' perceptions of workplace fairness that is based on the amount and the truthfulness of information that organizations provide to their employees. Based on a sample of managers from manufacturing organizations, the Partial Least Square results indicate that comprehensive performance measurement systems (comprehensive PMS) have a significant direct effect on jobrelevant information. They also indicate that comprehensive PMS have an indirect effect on informational fairness via job-relevant information. In contrast, systems that are based on financial measures have no significant effects on job-relevant information and informational fairness. These results demonstrate how comprehensive PMS (through the communication of a greater amount of job-relevant information) can be used to engender employees' perceptions of high workplace fairnes

    Simpson's Paradox, Lord's Paradox, and Suppression Effects are the same phenomenon – the reversal paradox

    Get PDF
    This article discusses three statistical paradoxes that pervade epidemiological research: Simpson's paradox, Lord's paradox, and suppression. These paradoxes have important implications for the interpretation of evidence from observational studies. This article uses hypothetical scenarios to illustrate how the three paradoxes are different manifestations of one phenomenon – the reversal paradox – depending on whether the outcome and explanatory variables are categorical, continuous or a combination of both; this renders the issues and remedies for any one to be similar for all three. Although the three statistical paradoxes occur in different types of variables, they share the same characteristic: the association between two variables can be reversed, diminished, or enhanced when another variable is statistically controlled for. Understanding the concepts and theory behind these paradoxes provides insights into some controversial or contradictory research findings. These paradoxes show that prior knowledge and underlying causal theory play an important role in the statistical modelling of epidemiological data, where incorrect use of statistical models might produce consistent, replicable, yet erroneous results

    Assessing the Impact of Pumpkins Plantation, Harvest and Storage Decisions on a Collaborative Supply Chain with Data Analysis Tools

    Full text link
    [EN] Successful pumpkins production requires the use of varieties that jointly with other factors yield well and produce pumpkins of the size, shape, color, and quality demanded by the market. But not only these issues are important. The perishable nature of pumpkins makes other issues such as how to prevent deterioration after harvest to become also relevant. In this paper the pumpkins plantation, harvest and storage (PHS) process is described and how some decisions affect certain goals, such as yield or conservation time. Additionally, some decision-making insights in a supply chain collaborative scenario made up of two stages: plantation/harvest and storage are given, where yield and conservation time trade-offs are outlined to develop win-win strategies. A real case using data analysis tools is analyzed. Results provide guidelines not only to make decisions independently on each stage but also to collaboratively work.The authors acknowledge the support of the project 691249, RUCAPS: "Enhancing and implementing knowledge based ICT solutions within high risk and uncertain conditions for agriculture production systems", funded by the European Union's research and innovation programme under the H2020 Marie Skodowska-Curie Actions.Pérez Perales, D.; Rodríguez-Sánchez, MDLÁ.; Ortiz Bas, Á.; Guyon, C. (2020). Assessing the Impact of Pumpkins Plantation, Harvest and Storage Decisions on a Collaborative Supply Chain with Data Analysis Tools. IFIP Advances in Information and Communication Technology. 598:511-523. https://doi.org/10.1007/978-3-030-62412-5_42S511523598Prima, W.A., Xing, K., Amer, Y.: Collaboration and sustainable agri-food supply chain: a literature review. MATEC, 5802004 (2016)Pérez Perales, D., Alarcón Valero, F., Drummond, C., Ortiz, Á.: Towards a sustainable agri-food supply chain model. the case of LEAF. In: Ortiz, Á., Andrés Romano, C., Poler, R., García-Sabater, J.-P. (eds.) Engineering Digital Transformation. LNMIE, pp. 333–341. Springer, Cham (2019). https://doi.org/10.1007/978-3-319-96005-0_40Esteso, A., Alemany, M.M.E., Ortiz, A.: Conceptual framework for designing agri-food supply chains under uncertainty by mathematical programming models. Int. J. Prod. Res. 56(13), 4418–4446 (2018)Bahrami, R., Khodadadi, M., Piry, S., Hassanpanah, D.: The effects of planting methods and head pruning on seed yield and yield components of medicinal pumpkin (Cucurbita Pepo Subsp. Pepo Convar. Pepo Var. Styriaca) at low temperature areas. Pak. J. Bio. Sci. 12(6), 538–541 (2009)Tarus, W.J., Ochuodho, J.O., Rop, N.K.: Influence of harvesting stage on seed quality aspects of pumpkin (Cucurbita Pepo L.). J. Exp. Agr. 18(2), 1–9 (2017)Amodio, M.L., Rinaldi, R., Colell, G.: Extending shelf life of fresh-cut pumpkin (Cucurbita Maxima): effect of pre-treatments and storage conditions. Acta Hortic. 876, 333–340 (2010)Pimentel, D., et al.: Annual vs perennial grain production. Agric. Ecosyst. Environ. 161, 1–9 (2012)Biesiada, A., Nawirska, A., Kucharska, A., Sokół-Łętowska, A.: The effect of nitrogen fertilization methods on yield and chemical composition of pumpkin (Cucurbita maxima) fruits before and after storage. Veg. Crops. Res. B. 70, 203–211 (2009)Gwenael, J., Paul, Ch., Sau, I., Saurabh, S., Thomasse, S.: Hitting and harvesting pumpkins. Siam. J. Discrete. Math. 28(3), 1363–1390 (2014)Oluoch, M.O.: Production practices of pumpkins for improved productivity. Scripta. Hort. 15, 181–189 (2012)Ondigi, A., Toili, W., Ijani, A., Omuterema, S.: Comparative analysis of production practices and utilization of pumpkins (Cucurbita Pepo and Cucurbita Maxima) by smallholder farmers in the lake victoria basin, East Africa. Afr. J. Environ. Sci. Tech. 2(9), 296–304 (2008)Naik, M.L., Prasad, V.M., Raya, L.P.: A study on character association and path analysis in pumpkin (Cucurbita Moschata Duch. Ex Poir.). Int. J. Adv. Res. 3(1), 1030–1034 (2015)Nerson, H., Paris, H.S., Paris, E.P.: Fruit shape, size and seed yield in Cucurbita Pepo. Acta Hort. 510, 227–230 (2000)Ortiz, A., Alarcón, F., Pérez, D., Alemany, M.M.E.: Identifying the main uncertainties in the agri-food supply chain. In: Mula, J., Barbastefano, R., Díaz-Madroñero, M., Poler, R. (eds.) New global perspectives on industrial engineering and management. LNMIE, pp. 221–229. Springer, Cham (2019). https://doi.org/10.1007/978-3-319-93488-4_25Khalid, E., Mohammed, E.: Dependence of pumpkin yield on plant density and variety. Am. J. Plant. Sci. 2, 636–643 (2011)Jakop, M., et al.: Yield performance and agronomic efficiency in oil pumpkins (Cucurbita Pepo L. Group Pepo) depending on production systems and varieties. Agr. 14(1), 25–36 (2017)Ahmed, B., Masud, M.A.T., Zakaria, M., Hossain, M.M., Mian, M.A.K.: Evaluation of pumpkin (Cucurbita Moschata Duch. Ex Poir.) for yield and other characters. Bangl. J. Agr. Res. 42(1), 1–11 (2017)Zhao, J., et al.: Physicochemical and antioxidant properties of different pumpkin cultivars grown in China. Food Sci. Technol. 9(4), 308–316 (2015)Zhou, C., et al.: The effect of high hydrostatic pressure on the microbiological quality and physical–chemical characteristics of pumpkin (Cucurbita Maxima Duch.) during refrigerated storage. Innov. Food. Sci. Emerg. 21, 24–34 (2014)Loy, J.B.: Harvest period and storage affect biomass partitioning and attributes of eating quality in acorn squash (Cucurbita Pepo), Présenté à Cucurbitaceae, Asheville, North Carolina, USA, pp. 568–577 (2006)Nagao, A., Indou, T., Dohi, H.: Effects of curing condition and storage temperature on postharvest quality of squash fruit. J. Jpn. Soc. Hort. Sci. 60(1), 175–181 (1991)Habibunnisa, R., Prasad, R., Shivaiah, K.M.: Storage behaviour of minimally processed pumpkin (Cucurbita Maxima) under modified atmosphere packaging conditions. Eur. Food Res. Technol. 212(2), 165–169 (2001)Sharrock, K.R., Parkes, S.L.: Physiological changes during development and storage of fruit of buttercup squash in relation to their susceptibility to Rot. New. Zeal. J. Crop. Hort. 18(4), 185–196 (1990)Muzzaffar, S., Baba, W.N., Nazir, N., Masoodi, F.A., Bhat, M.M., Bazaz, R.: Effect of storage on physicochemical, microbial and antioxidant properties of pumpkin (Cucurbita Moschata) candy. Cog. Food. Agr. 2(1), 1163650 (2016)Rahman, M.A., Miaruddin, M., Khan, M.H.H., Masud, M.A.T., Begum, M.M.: Effect of storage periods on postharvest quality of pumpkin. Bangl. J. Agr. Res. 38(2), 247–255 (2013)Song, J., Wei, Q., Wang, X., Li, D., Liu, C., Zhang, M., Meng, L.: Degradation of carotenoids in dehydrated pumpkins as affected by different storage conditions. Food. Res. Int. 107, 130–136 (2018)Matová, A.: the influence of genotype and storage condition on the content of selected bioactive substances in the fruit of pumpkin (Cucurbita Moschata Duch.). J. Microbiol. Bioech. Food. Sci. 9(2), 288–292 (2019)Tilman, D., Balzer, C., Hill, J., Befort, B.L.: Global food demand and the sustainable intensification of agricultura. Proc. Natl. Acad. Sci. U. S. A. 108, 20260–20264 (2011)Wang, W., et al.: Multiple trade‐offs between maximizing yield and minimizing greenhouse gas production in Chinese rice croplands. Land. Degrad. Dev. (2020)Pleijel, H., Uddling, J.: Yield vs. quality trade-offs for wheat in response to carbon dioxide and ozone. Glob. Change. Biol. 18(2), 596–n/a (2011)Pedhazur, E.J., Schmelkin, L.P.: Measurement, Design, and Analysis: an Integrated Approach. Lawrence Erlbaum Associates, Hillsdale (1991
    corecore