Optimal Spot-Checking for Improving the Evaluation Quality of Crowdsourcing: Application to Peer Grading Systems

2020 ◽  
Vol 7 (4) ◽  
pp. 940-955 ◽  
Author(s):  
Wanyuan Wang ◽  
Bo An ◽  
Yichuan Jiang
Keyword(s):  
Grading Systems ◽  
Peer Grading

Economic Behavior of Information Acquisition: Impact on Peer Grading in Massive Open Online Courses

2021 ◽  
Author(s):  
Onesun Steve Yoo ◽  
Dongyuan Zhan
Keyword(s):  
Information Acquisition ◽  
Online Courses ◽  
Critical Issue ◽  
Economic Behavior ◽  
Massive Open Online Courses ◽  
Massive Open Online ◽  
Economic Agents ◽  
Grading Systems ◽  
Scale Shift ◽  
Peer Grading

A critical issue in operating massive open online courses (MOOCs) is the scalability of providing feedback. Because it is not feasible for instructors to grade a large number of students’ assignments, MOOCs use peer grading systems. Yoo and Zhan investigate the efficacy of that practice when student graders are considered rational economic agents. Using an economic model that characterizes the behavior of student graders, they analyse the accuracy of current peer grading scheme. Interestingly, they identify a systematic grading bias toward the mean, which discourages students from learning. To improve current practice, they propose a simple scale-shift grading scheme, which can simultaneously improve grading accuracy and adjust grading bias. They discuss how it can be readily implemented in practice with moderate involvement of the instructors and MOOCs.

Hardwood Log Grading in the United States—Part 1: A Historical Perspective

2019 ◽  
Vol 69 (2) ◽  
pp. 110-123
Author(s):  
Curt C. Hassler ◽  
Shawn T. Grushecky ◽  
Lawrence E. Osborn ◽  
Joseph F. McNeel
Keyword(s):  
Historical Perspective ◽  
Forest Products ◽  
The United States ◽  
Forest Products Industry ◽  
Department Of Agriculture ◽  
For Profit ◽  
Grading Systems ◽  
The Us ◽  
Accepted Standard

Abstract The ability to efficiently and consistently characterize the quality of hardwood sawlogs is an indispensable part of operating a hardwood sawmill. And it is equally important for buyers and sellers of hardwood logs to negotiate prices on a uniform basis of both scale and grade. While scaling of logs is relatively straightforward, assuming buyer and seller agree on a specific log rule to use (e.g., Doyle, Scriber, International), grading logs for the purposes of evaluating quality is more complex. Hardwood log grading is an essential component of any hardwood sawmill's operation and effectively sets the stage for profit or loss. Various efforts have been made to develop a standardized log grading system by both the forest products industry and the US Department of Agriculture Forest Service (USDAFS) since the beginning of the 20th century. However, even after over a century of effort, there is still no broadly accepted standard for grading hardwood logs. The purpose of this article is to document the historical evolution of hardwood log grading systems. Understanding the development of hardwood log grading systems over time can help to produce a better log grading standard in the future.

scholarly journals A RETROSPECTIVE: THREE QUARTERS OF A CENTURY AT THE HALIFAX FISHERIES RESEARCH LABORATORY

2005 ◽  
Vol 43 (1) ◽  
Author(s):  
James E. Stewart ◽  
Andrew Safer
Keyword(s):  
Technical Assistance ◽  
Frozen Storage ◽  
Fish Processing ◽  
Marine Oils ◽  
International Agencies ◽  
Grading Systems ◽  
Health Studies ◽  
The 1960S ◽  
High Degree

In 1925 a Fisheries Technological Program was begun in temporary quarters on the Halifax waterfront to provide scientific research and technical assistance to improve the handling, processing and quality of fisheries products in Atlantic Canada. From that date through to 1979 (with a move to permanent buildings next door) studies on fish processing (smoking, drying, fresh and frozen storage, protein stability, marine oils, enzymatic and bacterial spoilage and grading systems among others) were conducted and the results transferred to industry, government and international agencies with a high degree of success and benefits. After it was apparent that product quality was affected by the condition of fish prior to harvest, more effort was devoted to physiological studies of live fish. In the 1960s studies concerning live lobster storage and latterly technical support for developing aquaculture ventures, i.e. health studies, nutritional requirements, environmental needs and physical structures, were added. Following the termination of the technological program in 1979 the buildings were used to accommodate elements of the Fisheries Resource Branchuntil theY'could be re-Iocated in 1997. This retrospective traces the reasons for programs and offers brief sketches of the studies and their application.En 1925, un programme d'etudes technologiques sur les peches voyait Ie jour dans des locaux provisoires situes sur Ie front de mer d'Halifax (il a em menage dans un edifice permanent tout pres des locaux originaux par la suite). Le but du programme etait d'assurer une aide scientifique et technique afin d'ameliorer la manutention, la transformation, et la qualite des produits de la peche au Canada Atlantique. De 1925 jusqu'en 1979, Ie programme n'a jamais cesse ses activites. On y a etudie la transformation du poisson (fumage, sechage, entreposage de produits frais ou congeles, stabilite des protei.nes, huiles marines, deteriorationdes produits provoquee par des enzymes ou des bacteries et systemes de classement, entre autres choses), et on a transmis les resultats de ces etudes a I'industrie, aux gouvemements et aux agences internationales qui en ont retire de nombreux avantages; Lorsqu'il est devenu evident que la qualite du produit est egalcment influencec par I'etat du poisson avant la recolte, on a commencea consacrer davantage d'efforts aux etudes physiologiques du poisson vivant. Au cours des annees 1960, on a ajoute des etudes sur les conditions d'enti-eposage du homard vivant et, plus recemment,on s'est interesse aux besoins de l'industrie aquacole, a savoir l'etat de sante des poissons d'elevage, leurs besoins nutritifs, leurs besoins lies au milieu et les structures physiques. Quand le programme d'etudes technologiques a pris fin en 1979, les edifices ont ete utilises par certaines composantes de la Direction des ressources halieutiques jusqu 'a ce qu'elles amenagent dans d'autres locaux en 1997. Voici une retrospective de la raison d'etre des programmes,des etudes qui ont ete menees et de leurs applications.

scholarly journals Development of the Credit System in Kazakhstan

2019 ◽  
pp. 28-30
Author(s):  
Aray Kozyevna Ilyassova-Schoenfeld
Keyword(s):  
Higher Education ◽  
Educational System ◽  
Cultural Background ◽  
System Model ◽  
Credit System ◽  
Grading Systems

Since independence in 1991, Kazakhstan has had the aim to increase the quality of its higher education. The system has a strong Soviet educational legacy. By constantly reforming its educational system, Kazakhstan has attempted to become a part of both the European and the American systems. The credit system employed at Kazakhstani universities is unique. It evolved from a time when graduates of the Soviet educational system were required to prove their qualifications and degrees by calculating or converting their learning hours into international grading systems. It took a long journey before Kazakhstan introduced its own credit system model, preserving the country’s political, ideological, economic, social and cultural background.

REVIEW OF TREATMENT TRIALS IN HUMANSPINAL CORD INJURY

Neurosurgery ◽  
2006 ◽  
Vol 59 (5) ◽  
pp. 957-987 ◽  
Author(s):  
Charles H. Tator
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Phase I ◽  
Treatment Trials ◽  
Prospective Control ◽  
Large Numbers ◽  
Grading Systems ◽  
Cord Injury ◽  
The 1960S

Abstract OBJECTIVE To provide a comprehensive review of the treatment trials in the field of spinal cord injury, emphasizing what has been learned about the effectiveness of the agents and strategies tested and the quality of the methodology. The review aims to provide useful information for the improvement of future trials. The review audience includes practitioners, researchers, and consumers. METHODS All publications describing organized trials since the 1960s were analyzed in detail, emphasizing randomized, prospective controlled trials and published Phase I and II trials. Trials were categorized into neuroprotection, surgery, regeneration, and rehabilitation trials. Special attention was paid to design, outcome measures, and case selection. RESULTS There are 10 randomized prospective control trials in the acute phase that have provided much useful information. Current neurological grading systems are greatly improved, but still have significant shortcomings, and independent, trained, and blinded examiners are mandatory. Other trial designs should be considered, especially those using adaptive randomization. Only methylprednisolone and thyrotropin-releasing hormone have been shown to be effective, but the results of the former are controversial, and studies involving the latter involved too few patients. None of the surgical trials has proven effectiveness. Currently, a multitude of cell-based Phase I trials in several countries are attracting large numbers of patients, but such treatments are unproven in effectiveness and may cause harm. Only a small number are being conducted in a randomized or blinded format. Several consortia have committed to a promise to improve the conduct of trials. CONCLUSION A large number of trials in the field of spinal cord injury have been conducted, but with few proven gains for patients. This review reveals several shortcomings in trial design and makes several recommendations for improvement.

Meat quality of heifers fattened to heavy weights to enhance marbling

1997 ◽  
Vol 77 (4) ◽  
pp. 635-643 ◽  
Author(s):  
P. L. Dubeski ◽  
J. L. Aalhus ◽  
S. D. M. Jones ◽  
W. M. Robertson ◽  
R. S. Dyck
Keyword(s):  
Meat Quality ◽  
Shear Force ◽  
Extended Period ◽  
Intramuscular Fat ◽  
The Other ◽  
Slaughter Weight ◽  
Lower Shear ◽  
Grading Systems ◽  
Cattle Meat

Marbling is the primary factor affecting quality grades of youthful grain-fed cattle in the Canadian, American and Japanese grading systems. Cattle were fed for an extended period of time and to extreme slaughter weights to enhance marbling. The effects of slaughter weight, breed, nutrition, and grading site (12/13th rib-Canadian or 6/7th rib-Japanese) on meat quality were evaluated using 221 weaned heifer calves (exp. 1) and 216 yearling heifers (exp. 2) raised on high (HP) or moderate-high (MHP) planes of nutrition. Mean intramuscular fat concentration in longissimus muscle was 6.93, 8.94, and 9.86% at mean slaughter weights of 500, 590, and 680 kg, respectively (exp 1) and 6.84% and 9.02% at 590 and 680 kg (exp. 2). HP carcasses had more intramuscular fat and lower shear values and drip losses than MHP carcasses (P ≤ 0.05). Angus carcasses had more intramuscular fat and lower shear values than the other breeds studied. Holsteins on the HP diet produced tender meat with a high amount of intramuscular fat whereas Holsteins on the MHP diet produced tougher meat with less intramuscular fat (P < 0.05). The 6/7th rib site had lower marbling scores, lighter meat, higher drip losses and lower shear values (P ≤ 0.001) than the 12/13th rib site. Intramuscular fat accounted for only 3 to 7% of the variation in shear force. Breed, nutrition, and slaughter weight had little effect on most measurements of meat quality except intramuscular fat and shear force. Key words: Beef cattle, meat quality, intramuscular fat, tenderness

Immunoferritin localization of intracellular antigens in positively stained frozen sections

1978 ◽  
Vol 36 (2) ◽  
pp. 168-169
Author(s):  
K. T. Tokuyasu
Keyword(s):  
Surface Tension ◽  
Water Surface ◽  
Thin Layers ◽  
The Other ◽  
Positive Staining ◽  
Frozen Sections ◽  
The Past ◽  
Ultrathin Frozen Sections ◽  
Definition Of

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).

Lithography below 100 nm

1983 ◽  
Vol 41 ◽  
pp. 96-99
Author(s):  
L. D. Jackel
Keyword(s):  
Spatial Distribution ◽  
Electron Beam ◽  
Electron Scattering ◽  
Electron Beam Lithography ◽  
Substrate Material ◽  
Local Electron ◽  
Electron Dose ◽  
Positive Resist ◽  
Exposure Process

Most production electron beam lithography systems can pattern minimum features a few tenths of a micron across. Linewidth in these systems is usually limited by the quality of the exposing beam and by electron scattering in the resist and substrate. By using a smaller spot along with exposure techniques that minimize scattering and its effects, laboratory e-beam lithography systems can now make features hundredths of a micron wide on standard substrate material. This talk will outline sane of these high- resolution e-beam lithography techniques.We first consider parameters of the exposure process that limit resolution in organic resists. For concreteness suppose that we have a “positive” resist in which exposing electrons break bonds in the resist molecules thus increasing the exposed resist's solubility in a developer. Ihe attainable resolution is obviously limited by the overall width of the exposing beam, but the spatial distribution of the beam intensity, the beam “profile” , also contributes to the resolution. Depending on the local electron dose, more or less resist bonds are broken resulting in slower or faster dissolution in the developer.

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