Computational Issues in the Statistical Design and Analysis of Experimental Games

One goal of experimental economics is to provide data to identify models that best describe the behavior of experimental subjects and, more generally, human economic behavior. We discuss here what we think are the three main steps required to make experimental investigations of economic games as statistically informative as possible: finding the solution of the experimental game under the postulated equilibrium or other economic models, selecting from a potential class of experimental designs the optimal one for discriminating between those models, and choosing an optimal stopping rule that indicates when to stop sampling data and accept one model as the best explanation of the data. Each step can be computationally intensive. We offer an algorithmic presentation of the necessary computations in each of the three steps and illustrate these procedures by examples from our research on learning models in experimental games with incomplete information. These three steps of experimental design and analysis are not limited to experimental games, but the computational burden of implementing these algorithms in other experimental environments - for example, market experiments - requires further considerations with which we have not dealt

The effect of serum angiotensin II and angiotensin II type 1 receptor gene polymorphism on pediatric lupus nephritis

Background: Angiotensin II (Ang II) is found to perpetuate inflammation and visceral damage in systemic lupus erythematosus (SLE). It mediates most of its actions through Ang II receptor type I (AT1) whose gene polymorphism A1166C (CC genotype) seems to have pathogenic effects. Objective: To measure serum Ang II and the frequency of AT1 receptor CC genotype among a group of Egyptian patients with pediatric onset lupus nephritis (pLN). Methods: This is a case-control cross sectional study which included 24 patients with pLN and 24 age and sex-matched healthy subjects as controls. Clinical evaluation and routine laboratory markers for SLE patients were done. SLE disease activity index (SLEDAI) and the British Isles Lupus Assessment Group (BILAG)-2004 renal score were measured. Serum Ang II was measured by enzyme linked immunosorbent assay and detection of ATI receptor CC genotype by polymerase chain reaction were done for both patients and controls. Results: Patients had significantly higher serum Ang II than the controls (p=0.0001). The frequency of AT1 receptor CC genotype was significantly higher among patients as compared to the control group (p=0.008). Both serum Ang II and AT1 receptor CC genotype were comparable between patients with proliferative LN class III and IV and those with LN class II (p>0.05). Serum Ang II did not correlate significantly with SLEDAI or BILAG-renal score (p>0.05). Conclusion: Serum Ang II and AT1 receptor CC genotype seem to have pathogenic role in pLN but with no deleterious effects on the phenotype of LN for further assessment.Keywords: Lupus nephritis; Angiotensin II; Angiotensin II type 1 receptor; Polymorphism; Pediatrics

Seminavis aegyptiaca sp. Nov., a new amphoroid diatom species from estuary epilithon of the river–nile damietta branch, Egypt

During a recent floristic–taxonomic study on the algal flora, including diatoms, from the estuary of the Damietta Branch of the Nile in Egypt, an interesting epilithic diatom species belonging to the genus Seminavis (Naviculaceae) was collected and investigated using both light and scanning electron microscopy. This new diatom species shares morphologically some taxonomic diagnostic features with other related taxa such as S. insignis, S. robusta, and S. ventricosa. However, it still differs by having ventral central striae that are shorter and more or less straight in the middle of the smaller frustules to be clearly radiate in the larger ones and then become geniculate and only radiate near the poles, the central raphe endings are externally more distantly spaced than in the similar species, the elongate central nodule is internally less prominent, and the areola density is much denser. Therefore, we here describe it as Seminavis aegyptiaca sp. nov. Hydrochemical analyses revealed that S. aegyptiaca commonly inhabits typical marine, with a weak tendency towards brackish water, habitats. It was found to be tolerant to meso–eutrophic, nutrient–enriched conditions, based on the data available on seasonal concentrations of N and P compounds. These findings not only contribute to the inventory of Egyptian diatoms, but also increase our understanding of the autecology and distribution of this relatively poorly–known diatom genus

Seminavis aegyptiaca sp. nov., a new amphoroid diatom species from estuary epilithon of the River-Nile Damietta Branch, Egypt

[EN] During a recent floristic–taxonomic study on the algal flora, including diatoms, from the estuary of the Damietta Branch of the Nile in Egypt, an interesting epilithic diatom species belonging to the genus Seminavis (Naviculaceae) was collected and investigated using both light and scanning electron microscopy. This new diatom species shares morphologically some taxonomic diagnostic features with other related taxa such as S. insignis, S. robusta, and S. ventricosa. However, it still differs by having ventral central striae that are shorter and more or less straight in the middle of the smaller frustules to be clearly radiate in the larger ones and then become geniculate and only radiate near the poles, the central raphe endings are externally more distantly spaced than in the similar species, the elongate central nodule is internally less prominent, and the areola density is much denser. Therefore, we here describe it as Seminavis aegyptiaca sp. nov. Hydrochemical analyses revealed that S. aegyptiaca commonly inhabits typical marine, with a weak tendency towards brackish water, habitats. It was found to be tolerant to meso–eutrophic, nutrient–enriched conditions, based on the data available on seasonal concentrations of N and P compounds. These findings not only contribute to the inventory of Egyptian diatoms, but also increase our understanding of the autecology and distribution of this relatively poorly–known diatom genusSIThis work was a part of the PhyBiO project funded by the Italian Ministry of Foreign Affairs and International Cooperation (MAECI) to the MUSE Post–Doc Abdullah A. Saber for the academic year 2018/201

Crystal structure of tert-butyl 2-phenylethylcarbamate, C13H19NO2

Abstract C13H19NO2, monoclinic, P21/n (no. 14), a = 5.2692(3) Å, b = 13.8663(9) Å, c = 17.8020(13) Å, β = 93.323(6)°, V = 1298.50(15), Z = 4, R gt(F) = 0.0590, wR ref(F 2) = 0.1932, T = 293 K.</jats:p

Evaluating neural networks as a method for identifying students in need of assistance

© 2017 ACM. Course instructors need to be able to identify students in need of assistance as early in the course as possible. Recent work has suggested that machine learning approaches applied to snapshots of small programming exercises may be an effective solution to this problem. However, these results have been obtained using data from a single institution, and prior work using features extracted from student code has been highly sensitive to differences in context. This work provides two contributions: first, a partial reproduction of previously published results, but in a different context, and second, an exploration of the efficacy of neural networks in solving this problem. Our findings confirm the importance of two features (the number of steps required to solve a problem and the correctness of key problems), indicate that machine learning techniques are relatively stable across contexts (both across terms in a single course and across courses), and suggest that neural network based approaches are as effective as the best Bayesian and decision tree methods. Furthermore, neural networks can be tuned to be reliably pessimistic, so they may serve a complementary role in solving the problem of identifying students who need assistance

Crystal structure of 4-(benzofuran-2-yl)-2-(3-(4-fluorophenyl)-3,3a,4,5-tetrahydro-2H-benzo[g]indazol-2-yl)thiazole, C28H20FN3OS

Abstract C28H20FN3OS, triclinic, P1̅ (no. 2), a = 9.5719(5) Å, b = 10.7499(6) Å, c = 10.9238(5) Å, α = 95.470(4)°, β = 102.133(4)°, γ = 97.962(4)°, V = 1079.30(10) Å3, R gt(F) = 0.0482, wR ref(F 2) = 0.1143, T = 150(2) K.</jats:p