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101.
Lawrence T. DeCarlo 《Journal of Educational Measurement》2005,42(1):53-76
An approach to essay grading based on signal detection theory (SDT) is presented. SDT offers a basis for understanding rater behavior with respect to the scoring of construct responses, in that it provides a theory of psychological processes underlying the raters' behavior. The approach also provides measures of the precision of the raters and the accuracy of classifications. An application of latent class SDT to essay grading is detailed, and similarities to and differences from item response theory (IRT) are noted. The validity and utility of classifications obtained from the SDT model and scores obtained from IRT models are compared. Validity coefficients were found to be about equal in magnitude across SDT and IRT models. Results from a simulation study of a 5-class SDT model with eight raters are also presented. 相似文献
102.
Do young boys and girls understand what leads to academic success (e.g., talent, effort, good teaching, luck) in the same way? Do young girls and boys have equivalent perceptions of their academic competence? Are these beliefs engendered in the same way across sociocultural contexts? In a cross-cultural study of over 3,000 children in grades 2 to 6, ages 7.2 to 13.6, we discovered that boys and girls around the world have very similar ideas about what generally leads to academic success. Moreover, in the few contexts where boys' and girls' academic performances were equal, their beliefs were also equal. However, when girls outperformed boys, their beliefs in their own talent were no greater than boys' beliefs, even though they did have stronger beliefs than boys in other facets of their achievement potential (e.g., putting forth effort, being lucky, getting their teacher's help). Our findings support the generally close correspondence between children's achievement and their competence-related beliefs, with the exception that young girls appear to specifically discount their talent. The effects held regardless of the children's achievement, intelligence, or age (approximately 8 to 13 years). Girls were more biased in some contexts than in others, however, suggesting that competence-related biases are rooted in culture-specific aspects of school settings. 相似文献
103.
知识管理在中美教育机构中的应用研究 总被引:9,自引:0,他引:9
目前知识管理在教育机构中的应用较为滞后 ,但其思想和方法同样适用于像大学、教育管理部门这样的组织机构。教育机构也可以通过实施知识管理达到提高响应能力和工作效率的目的。在高等教育中 ,知识管理工作体现在面向学生的教学和管理活动中。通过对中美两国教育机构调研的数据分析可以看出 ,在与知识管理相关的因素分析上 ,如知识管理的实施与激励形式、作用力和学校规模等方面 ,中国学校与美国学校在认识上具有不同的相关程度。这些差异反映了两国知识管理发展水平的不同 ,同时 ,对中国的高校实施知识管理具有启发意义 ,即知识管理本身本非目的 ,而是一种手段 ,应将它同具体的工作有机结合 ,才能取得更好的效果。 相似文献
104.
Urinary citric acid and calcium levels have been estimated in the urine of 20 normal healthy persons as well as 12 urinary
stone patients. Inhibition efficiency of these urine samples towards the mineralisation of urinary stone forming minerals,
viz., calcium phosphate, oxalate or carbonate, has been studied in an experimental model. Statistical correlation of the above
data has been made by computing the coefficient of determination and unexplained variance. Clinico-biochemical indexing of
calcium urolithiasis risk factor has been attempted in the light of the data. 相似文献
105.
K. Pratibha T. Seenappa K. Ranganath 《Indian journal of clinical biochemistry : IJCB》2007,22(2):158-161
Alkaptonuria, a metabolic disorder characterized by a triad of homogentisic aciduria, arthritis and ochronosis is one of the
first conditions in the charter of group of inborn errors of metabolism proposed to have Mendelian recessive inheritance.
It is due to the deficiency of the enzyme homogentisic acid oxidase which catalyzes the conversion of homogentisic acid to
maleylacetoacetic acid in the catabolism of tyrosine. Homogentisic acid thus accumulates in cells and body fluids and its
oxidized polymers bind to collagen, leading to progressive deposition of grey to bluish black pigment resulting in degenerative
changes in cartilage, intervertebral disc and other connective tissues, leading to arthritis which is the only disabling effect
in an affected older individual. However the diagnosis can be made in neonates when blackish stain is noticed in an unwashed
diaper. Alkaptonuria is treated symptomatically, surgical intervention necessitates in advanced stages, treatment with ascorbic
acid (Vitamin C) and dietary restrictions of food containing phenylalanine and tyrosine have proved to be successful in alleviating
the symptoms. 相似文献
106.
H.T. Chieh 《Journal of The Franklin Institute》1973,295(1):69-79
An effective way of constructing transforming matrix which similarly transforms a real square matrix to a quasi-diagonal form, is obtained. The transforming matrix as well as the quasi-diagonal form are real, regardless whether the given matrix has real eigenvalues or not. Formulas are included; they can be applied conveniently to evaluate a matrix function f(A) from the given scalar function f(λ). Three examples are given to illustrate the ease of application. These are the solutions of system differential equations of first and second order, and the determination of Nth root of a square matrix. 相似文献
107.
T. Malati G. Rajani Kumari P. V. L. N. Murthy Ch. Ram Reddy B. Surya Prakash 《Indian journal of clinical biochemistry : IJCB》2006,21(1):34-40
Prostate Specific Antigen (PSA) has emerged as the most applicable and important tumor marker for carcinoma prostate. In the
present study PSA was determined in serum of healthy subjects, patients of benign prostate hypertrophy (BPH) and Carcinoma
Prostate (Ca−P) to evaluate its diagnostic efficiency in day to day management of prostate cancer patients and in differentiating
patients of early prostate cancer from those with BPH. Receiver operating characteristic curve (ROC) revealed 2 ng/ml and
10 ng/ml cut off serum PSA level for BPH and untreated carcinoma prostate patients (Ca−P). An extremely significant increase
(P<0.0001) was observed in mean PSA concentration in BPH patients and adenocarcinoma prostate patients when compared to healthy
males. Clinical relevance of PSA was highlighted by a case study of cancer patient prior to any therapy till death. 相似文献
108.
Shilpa Sivashankar Sumeyra Agambayev Yousof Mashraei Er Qiang Li Sigurdur T. Thoroddsen Khaled Nabil Salama 《Biomicrofluidics》2016,10(3)
This paper proposes a new “twisted” 3D microfluidic mixer fabricated by a laser writing/microfabrication technique. Effective and efficient mixing using the twisted micromixers can be obtained by combining two general chaotic mixing mechanisms: splitting/recombining and chaotic advection. The lamination of mixer units provides the splitting and recombination mechanism when the quadrant of circles is arranged in a two-layered serial arrangement of mixing units. The overall 3D path of the microchannel introduces the advection. An experimental investigation using chemical solutions revealed that these novel 3D passive microfluidic mixers were stable and could be operated at a wide range of flow rates. This micromixer finds application in the manipulation of tiny volumes of liquids that are crucial in diagnostics. The mixing performance was evaluated by dye visualization, and using a pH test that determined the chemical reaction of the solutions. A comparison of the tornado-mixer with this twisted micromixer was made to evaluate the efficiency of mixing. The efficiency of mixing was calculated within the channel by acquiring intensities using ImageJ software. Results suggested that efficient mixing can be obtained when more than 3 units were consecutively placed. The geometry of the device, which has a length of 30 mm, enables the device to be integrated with micro total analysis systems and other lab-on-chip devices. 相似文献
109.
110.
Middle grades science teachers need professional support in practice as they implement new inquiry-based science. Professional
development schools can provide this bottom-up support through connecting preservice and inservice teacher education programs
in classroom practice. In this study, coteaching arrangements with secondary science education majors provided additional
teachers in the classroom to support a materials-rich curriculum and the needed associated pedagogies. Science education majors
provided needed assistance in troubleshooting difficulties with the new curriculum. They also provided needed content knowledge
to support inquiry, along with creating moments and space for teachers to reflect on inquiry practice. Ongoing assistance
by preservice teachers allowed inservice teachers to progress from logistical concerns in implementing kit curriculum to concerns
regarding student learning and the supporting professional development.
相似文献
Charles J. EickEmail: |