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We present a conceptual framework of teacher turnover, which is guided by the broader employee turnover literature and supported by the empirical literature. Synthesising nearly forty years of inte...

Taking time to identify expected products and waiting for the checkout in a retail store are common scenes we all encounter in our daily lives. The realization of automatic product recognition has great significance for both economic and social progress because it is more reliable than manual operation and time-saving. Product recognition via images is a challenging task in the field of computer vision. It receives increasing consideration due to the great application prospect, such as automatic checkout, stock tracking, planogram compliance, and visually impaired assistance. In recent years, deep learning enjoys a flourishing evolution with tremendous achievements in image classification and object detection. This article aims to present a comprehensive literature review of recent research on deep learning-based retail product recognition. More specifically, this paper reviews the key challenges of deep learning for retail product recognition and discusses potential techniques that can be helpful for the research of the topic. Next, we provide the details of public datasets which could be used for deep learning. Finally, we conclude the current progress and point new perspectives to the research of related fields.

The No Child Left Behind Act (NCLB) has been criticized for encouraging schools to neglect students whose performance exceeds the proficiency threshold or lies so far below it that there is no reasonable prospect of closing the gap during the current year. We examine this hypothesis using longitudinal data from 2002–03 through 2005–06. Our identification strategy relies on the fact that as NCLB was phased in, states had some latitude in designating which grades were to count for purposes of a school making adequate yearly progress. We compare the mathematics achievement distribution in a grade before and after it became a high-stakes grade. We find in general no evidence that gains were concentrated on students near the proficiency standard at the expense of students scoring much lower, though there are inconsistent signs of a trade-off with students at the upper end of the distribution.

Rigorous research examining the correlates of teacher turnover has grown in recent years. However, the most recent meta-analytic synthesis of this literature was published over a decade ago. To update our collective understanding and highlight advances in this literature, this meta-analysis reviews findings from 120 studies of factors associated with teacher turnover. In addition to providing a novel synthesis using the most up-to-date meta-analytic methods and better quality data than ever before, we contribute evidence to support an expanded conceptual framework for understanding teacher turnover. This framework adds several underexamined factors influencing teacher turnover, provides more nuance to factors previously studied, highlights the growing influence of educational policies external to the school, and accounts for an emerging awareness of the interplay between teacher and school characteristics. This paper reports both results for how various teacher, school, and workforce factors are associated with teacher turnover and discusses the policy implications using our expanded theoretical framework.

Korrektur zu 10.1038/s41375-020-0826-9

Using 7 years of student achievement data from a large urban school district in the south, this study examines the sorting of teachers’ value-added effectiveness estimates by student demographics and considers factors that may contribute to such sorting. We find that students in schools in the highest quartile of minority enrollments have teachers with value-added estimates that are about 0.11 of a student-level standard deviation lower than their peers in schools in the lowest minority quartile. However, neither teacher mobility patterns nor between-school differences in teacher qualifications seems responsible for this sorting. Though the highest minority schools face higher teacher turnover, they do not disproportionately lose their highest value-added teachers, nor are teachers with high value-added systematically migrating to lower-minority schools. Instead, teachers in the highest minority schools have lower value-added on average, regardless of experience. We find suggestive but inconclusive evidence that teachers’ improvement rates differ by minority-enrollment quartile.

Our aim in this article is to draw attention to some underappreciated problems in the design and implementation of evaluation systems that incorporate value-added measures. We focus on four: (1) taking into account measurement error in teacher assessments, (2) revising teachers’ scores as more information becomes available about their students, and (3) and (4) minimizing opportunistic behavior by teachers during roster verification and the supervision of exams.

The Project on Incentives in Teaching (POINT) was a three-year study testing the hypothesis that rewarding teachers for improved student scores on standardized tests would cause scores to rise. Results, as described in Springer et al. (2010b), did not confirm this hypothesis. In this article we provide additional information on the POINT study that may be of particular interest to researchers contemplating their own studies of similar policies. Our discussion focuses on the policy environment in which POINT was launched, considerations that affected the design of POINT, and a variety of lessons learned from the implementation of the experiment. © 2012 Association for Education Finance and Policy

This paper provides a review of the current teacher compensation system and examines the structure of teacher compensation in the U.S. K-12 public education system. Teacher salaries are largely set by schedules that are neither performancerelated nor market-driven, and have signifi cant consequences on school staffi ng and workforce quality. The second section summarizes the recent literature on compensation reform, with an emphasis on studies using experimental or quasiexperimental designs to evaluate the impact of programs on student achievement and teacher outcomes. A fi nal section offers observations on prospects for future research and reforms.

Pay for performance is poised to become more reality than simple rhetoric, but much work must be done to ensure these programs are effective.

Previous research on the effect of accountability programs on the distribution of student test score gains is decidedly mixed. This study examines the issue by estimating an educational production function in which test score gains are a function of the incentives schools have to focus instruction on below-proficient students. NCLB's threat of sanctions are positively correlated with test score gains by below-proficient students in failing schools; greater than expected test score gains by below-proficient students do not occur at the expense of high-performing students in failing schools. This pattern of results tends to suggest that failing schools were able to benefit low-performing students in ways that were consistent with having operational slack, and that the threat of sanctions may stimulate greater productivity within failing schools.

While there is a wealth of research on school finance equity and adequacy, and school finance theory clearly documents differences between the two concepts, no study has examined whether the reforms engendered by each approach actually differ in terms of resource distribution. The present study examines the issues using district‐level data on expenditure by function from two, large national data‐sets: the US Census of Governments School System Finance File F‐33 (1972–2002) and the National Center for Education Statistics’ Longitudinal School District Fiscal–Nonfiscal File (1990–2000). A difference‐in‐differences estimator with state and year fixed effects indicates that both court‐mandated equity and adequacy reforms decrease resource inequities. However, estimates based on data from the F‐33 file show negligible differences between equity and adequacy reforms, while estimates based on data from the Fiscal–Nonfiscal File indicate adequacy reform does not decrease horizontal inequities as much as court‐man...

Like many other states, Missouri has gone through several rounds of school finance litigation. However, the trial just concluded was unusual in two respects. First, three taxpayers were allowed to intervene for the defense and, in the process, raise important questions concerning the efficiency of school spending and broader questions of school reform. Second, the outcome at the circuit court level, which focused nearly entirely on points of law, was a complete victory for the defense. This article provides an overview of disputes of Missouri school finance and evidence pertaining to some of the points in dispute at the trial. These lessons generalize to other states facing school finance litigation. The authors conclude that changes in school funding formulas, and the seemingly interminable litigation about those formulas, are not an effective vehicle for addressing achievement gaps or the overall level of school performance.

Background: Unicystic ameloblastomas (UAs) and dentigerous cysts (DCs) have an identical clinical and radiographic appearance. Some subtypes of UAs have a better prognosis than solid or multicystic ameloblastomas, and simple enucleation is the adequate treatment. The present study was designed to test the hypothesis that UAs with small islands of ameloblastomatous epithelium may be misdiagnosed as a DC or keratocyst if no more than two histologic sections are examined. Methods: A total of 101 resection specimens from 22 women and 73 men (mean age: 46.5 years) were selected, all showing the clinical and radiographic features of a DC. Only cysts with a minimum diameter of 15 mm in the panoramic X-ray were considered for the present investigation. The histopathologic diagnosis had been routinely established by examining two sections. For our study, the specimens were investigated by step sections at 50 µm and by staining of 5 µm thin sections with hematoxylin and eosin (H&E) at 1 mm levels. An average of 15 slides were evaluated per case. Results: Microscopic examination of the step sections did not reveal ameloblastomatous epithelium in the cyst lining epithelium of the 101 cases. Thus, every primary diagnosis of a dentigerous cyst was confirmed. In four cases, additional rather large odentogenic cell nests were detected with palisading of basaloid cells, while there was a lack of other signs of ameloblastic differentiation. All lesions were completely resected, and no additional treatment was performed. Conclusions: Step sectioning of larger DCs may reveal associated odontogenic cell nests in some cases but does not lead to the detection of formerly missed ameloblastic cells. Thus, unicystic ameloblastomas are not misdiagnosed if only two slides are prepared for routine diagnosis of DCs.

Background Overlapping molecular pathways of inflammation have been implicated in periodontitis and rheumatoid arthritis (RA). The presence of shared underlying inflammatory pathogenesis mediating the progression of periodontitis and RA could provide potentially important common therapeutic targets. Objectives The primary purpose of this observational study was to determine the effect of methotrexate (MTX) and anti-TNFα (etanercept) on clinical parameters of periodontitis. Influence of periodontitis on efficacy of medical treatment of RA was a secondary endpoint. Methods Fourteen treatment-naive patients starting with MTX and 12 patients starting with anti-TNFα therapy, fulfilling the ACR/EULAR classification criteria for RA (2010), older than 18 years, and with natural dentition were included. One patient was excluded because of antibiotic use for oral infection P. gingivalis was determined by anaerobic culture. In addition, radiographic intra-oral pathologies (furcation involvement, peri-apical pathology and caries) were assessed on panoramic radiographs. Oral hygiene was measured using full mouth plaque scores. Efficacy of anti-rheumatic treatment was measured by change in RA disease activity (DAS28-ESR). Results Treatment with MTX of anti-TNFα significantly improved DAS scores (both p Conclusions Anti-rheumatic treatment did not have significant impact on clinical periodontal parameters. Within the limitations of this study (PISA scores were rather low) PISA and presence of other intra-oral pathologies were not of associated with efficacy of anti-rheumatic treatment. References Nesse, W., Abbas, F., van der Ploeg, I., Spijkervet, F.K., Dijkstra, P.U. & Vissink, A. (2008) Periodontal inflamed surface area: quantifying inflammatory burden. J.Clin.Periodontol. 35, 668–673. Disclosure of Interest M. de Smit: None declared, M. Posthumus: None declared, A.-M. van Brenk: None declared, L. Oosting: None declared, G. Springer: None declared, E. Brouwer: None declared, M. Bijl Grant/research support from: Pfizer, J. Westra: None declared

Ecsenius caeruliventris is described from the Banggai and Togean islands, closely adjacent to the mid-NE coast of Sulawesi. Ecsenius shirleyae is described from various islands situated between 106 02 E and 05 08 S. Both species are members of the Prooculis species group of Ecsenius, which now comprises eight species and which are differentiated from each other solely on the basis of color patterns. All of the species are distributed allopatrically except for E. bimaculatus, which, in the southern part of its range, occurs sympatrically with E. caeruliventris and, probably, E. shirleyae. New distributional records are provided for several species of Ecsenius.

Diffractive elements may be identified as miniaturised or micro optical components which affect an incoming beam of light by the laws of diffraction. In contrast to other micro optical components like refractive ball lenses and micro calottes or graded index lenses diffractive optics can be attributed as flat and in general aspheric optical elements which can perform multiple optical functions simultaneously.

The radiological diagnosis of distal radial fractures is usually easy, but some fractures without displacement cannot be detected at the first examination. In this retrospective study of 626 wrist injuries diagnosed as “wrist sprain” we found 39 distal radial fractures which were discovered only after repeated examinations. The incidence of distal radial fractures was much higher than other wrist fractures that were diagnosed after repeated examinations. Repeat standard four-view X-ray examination, as well as other imaging methods, are necessary to diagnose these fractures.

The stimulus suffix effect is investigated when it follows an auditory memory list in which rated meaningfulness was manipulated at the final serial position. A verbal suffix disrupts the terminal list item compared with a noise suffix, but rated meaningfulness affects recall performance significantly despite the presence of a verbal suffix. With ordered recall, there is some evidence that a verbal suffix disrupts items rated low in meaningfulness to a greater extent (Expt. I); this interaction does not show when serial order recall is stipulated (Expt. II). The effect of rated meaningfulness with a verbal stimulus suffix eliminates a model in which information about the final item is retrieved exclusively from precategorical acoustic storage. The paper discusses two propositions about the preliminary stages of acoustic analysis and encoding in the absence of focal attention.

The operational behaviour of two flexible manufacturing systems was investigated. A distinction was made between downtimes due to organisational causes and those due to technical causes. Duration of breakdowns, types of breakdowns and actions of the staff while operating the plant were analysed. Furthermore, a method for an uninterrupted description of the manufacturing routine of flexible manufacturing systems is presented, which can be used to improve operational behaviour.

An analytical method with a spatial resolution of less than 1 μm, a quantitative precision of about 1 % and the possibility — by means of scanning — of revealing concentration variations within an area of a few hundred microns, quite naturally arouses the interest of the mineralogist and it is therefore not surprising that the electron-probe microanalyser has become an indispensible research tool in many mineralogical laboratories.