Miracle-dz/UniFAR-FTUs huggingface dataset:
Cities, Productivity, and Trade

We document a novel stylized fact: Using data for several countries, we show that export activity is disproportionately concentrated in larger cities – even more so than overall economic activity. We account for this fact by marrying elements of international trade and economic geography. We build a model with agglomeration economies where firms with heterogeneous productivity sort across city sizes and select into exporting. The model allows us to study the geographic implications of trade policy, as well as the international trade effects of urban policies. We show that (i) lifting restrictions on housing supply raises not only the aggregate productivity of the economy but also its aggregate export intensity, by allowing more firms to locate in larger cities and profit from agglomeration effects; (ii) conversely, while opening up to trade has complex overall economic geography implications, within sectors it tends to shift employment towards larger cities. We structurally estimate the model using data for the universe of Chinese manufacturing firms and study the general equilibrium effects of trade liberalization and of urban policies. We find that the effects of these policies are quantitatively different from those predicted by trade models that ignore economic geography, and by economic geography models that omit international trade (both of which are nested in our framework).
Some Recent Advances in Avian Physiology

With primary attention to feral species, some important, recent trends in avian physiology have been selected and briefly described. Included are investigations of the exchanges of gases between embryo and external environment during incubation; structure and function of the lung-airsac system; avian energetics; control and energetic cost of molt; osmoregulation, ionoregulation and nitrogen excretion, including roles of kidney, lower gut, salt glands, and renin-angiotensin system; endocrinology; and orientation and navigation. Among these trends there has been an increase in the spectrum of species investigated, greater effort to make measurements under natural conditions and successes with experiments on feral species in the field. Physiological investigations have been facilitated by the great fund of information on the natural history and zoogeography of birds.
Interactive comment on “Long-term variation of sea ice and its response to thermodynamic factors in the Northwest Passage of the Canadian Arctic

Long-term variation of sea ice and its response to thermodynamic factors in the Northwest Passage of the Canadian Arctic Archipelago author by Shen et al. The manuscript (MS) is interesting and fits with the scope of the journal but unfortunately, the data and the interpretation are not well presented. As the authors have highlighted in the MS title “response to thermodynamic factors”, but fail to justify the factors. The authors have discussed only the relation with SST and SAT. To understand thermodynamics, we should know the mixed layer depth (MLD), then only we could know the ocean heat transport. In my opinion, the article cannot be published in that form needs a lot of substantial improvements and modifications: I, therefore, suggest the article cannot be accepted in the present form.
Dynamic Information Acquisition and Asset Prices

This paper studies the dynamics of information acquisition and uncertainty in a noisy rational expectations model. Investors choose to acquire most information at times when uncertainty and risk premia are high; this choice feeds back and endogenously reduces subsequent uncertainty. Within the model, uncertainty can be measured directly from risk-neutral variance—analogous to the VIX index—so this translates into the concrete prediction that risk-neutral variance mean-reverts rapidly following spikes in volatility, as is observed empirically. The cyclicality of information acquisition depends on the skewness of the underlying asset: if the market is negatively skewed, market-level information acquisition is countercyclical. Conversely, information acquisition and risk premia are high following good news for positively skewed assets such as individual stocks, which gives rise to momentum in the stock market.
The Effect of Chinese Competition on the Product Variety of Indian Firms

A few recent studies in the international trade literature indicates how import penetration or competition impacts labor market conditions, innovation and product variety of the importing country. However, almost the entire literature concentrates on the effect of rise in imports from the low-wage countries on the developed economies. We make one of the very first attempts to understand what happens when one of the two most technologically similar countries face competition from another. In particular, what is the impact of import penetration from China on the product variety of the Indian manufacturing firms? Using detailed firm-product-year data across manufacturing sectors in India spanning over one and half decades, and exploiting the exogenous nature of China's entry into the WTO in 2001, we investigate the potential link between the two. We find no effect of Chinese competition on the product variety of the Indian manufacturing firms at the aggregate. However, on dividing the firms by size, we find very robust and significant effect of creative destruction or product drop for the big firms. The big firms drop their peripheral products and concentrates on the core ones. This observation is acute for: (i) both exporters and non-exporters; (ii) domestic-private firms; (iii) both final and intermediate goods; and (iv) both high and low-exposure industries. We also find some evidence of product innovation for small firms. Our results are consistent to a battery of robustness checks. JEL classifications: F1, F14, F61
Borders and Distance in Knowledge Spillovers: Dying over Time or Dying with Age? – Evidence from Patent Citations

This paper uses a gravity framework to investigate the effects of distance as well as subnational and national borders in knowledge spillovers. Drawing on the NBER Patent Citations Database, we examine patent citations data at metropolitan level within the U.S. and the 38 largest patent-cited countries outside the U.S. We present 3 key findings: First, we find strong subnational localization effects at the Metropolitan Statistical Area (MSA) and state levels: more than 90% of intranational border effects stem from the metropolitan level rather than the state level, which is consistent with the artifact of geographic aggregation at the state level for trade flows as in Hillberry and Hummels (2008). Second, border and distance effects decrease with the age of cited patent, which implies that new knowledge faces the largest barriers to diffusion. However, over time, border and distance effects are interestingly increasing. Finally, we find that (assignee) self-citations and aggregation bias are two sources of overestimated aggregate border effects of knowledge spillovers. While self-citations are only 11% of total citations, they account for approximately 50% of MSA and national border effects.
Firm-Level Distortions and Aggregate Productivity: The Trade Channel

At the macro level, developing countries present low TFP and trade less than their size and geography would predict. At the micro level, they are characterized by small firm size and persistent within-industry misallocation. I develop a tractable multi-country general equilibrium model of production and international trade in which heterogeneous producers face both domestic distortions to firm size and costly entry into export markets. Since larger firms engage more intensely in international trade, misallocation induced by size distortions impacts aggregate productivity by also affecting the economy’s trade volumes and gains from trade. I explore the quantitative properties of the model calibrated to firm-level and aggregate data from the manufacturing sector of 77 major economies. I find that the trade channel greatly multiplies the effect of size distortions on aggregate TFP. Firm selection and factor reallocation amongst surviving firms totally account for this amplification, whereas the contribution from changes in firm entry is actually dampened by trade. Moreover, I find that cross-country differences in size distortions can account for a substantial share of the international dispersion in output per worker, but only when countries are integrated through trade. JEL classification: F12, F63, L25, O11, O47
Spatial Feedback Learning to Improve Semantic Segmentation in Hot Weather

High-temperature weather conditions induce geometrical distortions in images which can adversely affect the performance of a computer vision model performing downstream tasks such as semantic segmentation. The performance of such models has been shown to improve by adding a restoration network before a semantic segmentation network. The restoration network removes the geometrical distortions from the images and shows improved segmentation results. However, this approach suffers from a major architectural drawback that is the restoration network does not learn directly from the errors of the segmentation network. In other words, the restoration network is not task aware. In this work, we propose a semantic feedback learning approach, which improves the task of semantic segmentation giving a feedback response into the restoration network. This response works as an attend and ﬁx mechanism by focusing on those areas of an image where restoration needs improvement. Also, we proposed loss functions: Iterative Focal Loss (iFL) and Class-Balanced Iterative Focal Loss (CB-iFL), which are speciﬁcally designed to improve the performance of the feedback network. These losses focus more on those samples that are continuously miss-classiﬁed over successive iterations. Our approach gives a gain of 17.41 mIoU over the standard segmentation model, including the additional gain of 1.9 mIoU with CB-iFL on the Cityscapes dataset.
Prediction of moisture-density characteristics of compacted fill using mixture theory

This study presents a discussion of three prominent mixture models and assesses their predictive capabilities for several fly ash-modified soil mixtures. This study specifically focuses on the ability of the mixture models to predict moisture-density characteristics of compacted fill containing varying percentages of fly ash. The results of this study show that the behaviour of the mixture is a function of the fly ash component and the fractions of each component contained in the total mixture. This particular focus is in response to greater emphasis being placed on incorporating sustainability into geotechnical engineering. Specifically, it is hoped that the results of this study will be used to facilitate greater utilization of fly ash in earthwork construction. RESUMEN Este estudio presenta una discusión sobre tres importantes modelos de mezclas y se establecen sus capacidades predictivas para varias mezclas de suelo modificado con cenizas de carbón. Específicamente, este estudio se centra en la capacidad de los modelos de mezclas para predecir características de humedad-densidad de rellenos compactados con diferentes porcentajes de cenizas. Los resultados de este estudio muestran que el comportamiento de las mezclas es una función del contenido de cenizas y de la fracción de cada componente en el total de la mezcla. Este enfoque es una respuesta del gran énfasis puesto en incorporar la sostenibilidad en la ingeniería geotécnica. Específicamente, se espera que los resultados de este estudio sean usados para facilitar un mayor uso de las cenizas en construcción de obras geotécnicas.
Factors that influence job satisfaction among employees in public sector in Libya

Important factors that influence job satisfaction in the government organization are work environment, promotion and fairness. The association between these factors and job satisfaction have been established by previous studies in western countries. However, there is a lack of related studies in Libya that could extend the understanding of the relationship between these factors and job satisfaction. This study is conducted to address this gap. Specifically, the purpose of this study is to explore the factors that influence job satisfaction in Libyan public sector organizations. The data for this study has been collected from only one source which is the employees of public sector organization in Libya through a survey. The finding in this study shows that work environment, promotion and fairness have a significant role as predictors of job satisfaction in Libya. The finding clarify that management in public sector organizations in Libya need assure that the employees are well satisfied and they have the ability and encouragement to be satisfy and skills, in order to maximize job satisfaction the recently acquired satisfied and skills. This study extended the discussion and the understanding on the employee’s factors that influence job satisfaction in public sector organizations in Africa continent, specifically Libya, a developing country in North Africa.
The Death of Gamers: How Do We Address The Gamer Stereotype?

The clash of identities expressed in the Gamergate incident of 2014 was arguably intensified by the discourse of the “Gamers Are Dead” articles, which declared an end to gamers, meaning the prevalence of the gamer stereotype. This paper seeks to illuminate a novel angle of the Gamergate conflict by investigating how the gamer identity has been addressed through imagery in eight of the “Gamers Are Dead” articles of 2014. To do so, it discusses how the discourse of gamer identity, which is part of a larger ecology in game culture, may contribute to continued strife. To learn from the Gamergate crisis as a scholarly community, we unquestionably need to look at how discourse has been used to harm minorities, academics, and critics voicing their concerns about game culture. However, we also need to reflect on how critics affect the discourse of the gamer identity.
Increasing the resistance of common bean to white mold through recurrent selection

White mold, caused by Sclerotinea sclerotiorum (Lib.) de Bary is one of the most important diseases of the common bean (Phaseolus vulgaris L.) worldwide. Physiological resistance and traits related to disease avoidance such as architecture contribute to field resistance. The aim of this study was to verify the efficiency of recurrent selection in physiological resistance to white mold, “Carioca” grain type and upright habit in common bean. Thirteen common bean lines with partial resistance to white mold were intercrossed by means of a circulant diallel table, and seven recurrent selection cycles were obtained. Of these cycles, progenies of the S0:1, S0:2 and S0:3 generations of cycles III, IV, V and VI were evaluated. The best (8 to 10) progenies of the seven cycles were also evaluated, in two experiments, one in the greenhouse and one in the field. Lattice and/or randomized block experimental designs were used. The traits evaluated were: resistance to white mold by the straw test method, growth habit and grain type. The most resistant progenies were selected based on the average score of resistance to white mold. Subsequently, they were evaluated with regard to grain type and growth habit. Recurrent selection allowed for genetic progress of about 11 % per year for white mold resistance and about 15 % per year for the plant architecture. There was no gain among cycles for grain type. Progeny selection and recurrent selection were efficient for obtaining progenies with a high level of resistance to white mold with “Carioca” grain type and upright habit.
Effect of Inventory and Cash Conversion Cycles on Financial Performance of Listed Commercial and Service Firms in Nairobi Securities Exchange Kenya

DOI: 10.21276/sjebm.2018. 5.11. 2 Abstract: The main aim of the study was to analyze effect of inventory and cash conversion cycles on financial performance in Kenya; A Case Study of Listed Firms in the Commercial and Services Segment of Nairobi Securities Exchange. The study adopted the following theories; Operating Cycle Theory and Cash Conversion Cycle Theory. The study adopted descriptive research design which tested variables the way they occur in natural environment without interfering with them. The target population of the study was the 12 firms in the Commercial and Services Segment of Nairobi Securities Exchange. The study collected secondary data from audited accounts reports covering 2007 to 2017. The study purposively took census of all the firms in the commercial and service segment of which did not require sampling procedure. The researcher had a challenge in the companies which did not disclose some components of working capital on their financial statements but had to visit their company’s premises to access the data. Data was analyzed using panel data regression models and correlation analysis with the help of Stata Statistical Software to establish the combined influence of the four components of working capital management on financial performance. The study found out that that Inventory Conversion Period had no correlation with financial performance, r=. 509, p=. 050 indicating that Inventory Conversion Period affected financial performance of firms’ in the commercial segment of the NSE, Cash Conversion Cycle had no significant relationship with financial performance, r=. 001, p=. 073>. 05 indicating that Cash Conversion Cycle (CCC) did not affect financial performance of firms’ in the commercial segment of the NSE. The study recommends that firms’ in commercial and service segment in the NSE should enhance credit management to avoid over investment in accounts receivables. Collection policies should be reviewed in order to make the cash conversion cycle shorter for efficient working capital while keeping in view the intensity of competition. The study also recommends proper inventory management to avoid overstocking which could negatively affect financial performance. While coming up with inventory related policies. The study recommends that the firms should come up or enhance computerizing inventory management systems to track all inventory for actions that are less costly as far as holding inventory is concern.
Supplementary materials for Implicit competitive regularization in GANs

In Figure 1 we provide a larger reproduction of Figure 2 from the main paper. We see that also on the larger resolution, the third pair of images is visually indistinguishable, despite having the largest Euclidean distance of all pairs. The textures of this image are very rough, with a rapid alternation of bright and dark pixels. Therefore, a slight warping of the image will lead to dark pixels taking the place of bright ones and vice versa, leading to a large Euclidean distance. A similar effect could be achieved by the wind slightly moving the foliage between, for instance, successive frames of a video. Thus, this phenomenon could be observed in real images.
Mid-level Fusion for End-to-End Temporal Activity Detection in Untrimmed Video

In this paper, we address the problem of human activity detection in temporally untrimmed long video sequences, where the goal is to classify and temporally localize each activity instance in the input video. Inspired by the recent success of the single-stage object detection methods, we propose an end-to-end trainable framework capable of learning task-speciﬁc spatio-temporal features of a video sequence for direct classi-ﬁcation and localization of the activities. We, further, systematically investigate how and where to fuse multi-stream feature representations of a video and propose a new fusion strategy for temporal activity detection. Together with the proposed fusion strategy, the novel architecture sets new state-of-the-art on the highly challenging THUMOS’14 benchmark – up from 44.2% to 53.9% mAP (an absolute 9.7% improvement) .
When Tari¤s Disrupt Global Supply Chains

We study unanticipated tari¤s in a setting with rm-to- rm supply relationships. Firms that produce di¤erentiated products conduct costly searches for potential input suppliers and negotiate bilateral prices with those that pass a reservation level of match productivity. Global supply chains are formed in anticipation of free trade. Once they are in place, the home government surprises with an input tari¤. This can lead to renegotiation with initial suppliers or search for replacements. Calibrating the models parameters to the estimated price and quantity responses to the Trump tari¤s on imports from China, we nd a loss of welfare of just under 0.5% of GDP, an improvement of 2% in the U.S. terms of trade with China, and a deterioration of about 0.4% in the overall U.S. terms of trade. Keywords: global supply chains, global value chains, input tari¤s, imported intermediate goods JEL Classi cation: F13, F12 We are grateful to Pol Antràs, Harald Fadinger, Chaim Fershtman, Jerry Green, Faruk Gul, Gregor Jarosch, Edi Karni, Robin Lee, Mihai Manea, Emanuel Ornelas, Gianmarco Ottaviano, Richard Rogerson, Dan Treer, the editor, and four referees for helpful comments and suggestions and to Chad Bown for kindly sharing his tari¤ data. Benjamin Niswonger, Nan Xiang, and Xiang Zhang provided superb research assistance.
Contrasting evolutionary flexibility in sister groups: disparity and diversity in Mesozoic atelostomate echinoids

Abstract Temporal asymmetries in clade histories have often been studied in lower Paleozoic radiations. Post-Paleozoic patterns, however, are less well understood. In this paper, disparity and diversity changes in Mesozoic heart urchins were analyzed at the ordinal level, with contrasts among the sister groups Holasteroida and Spatangoida, their paraphyletic stem group Disasteroida, and the more inclusive clade, the superorder Atelostomata. A 38-dimensional landmark-based morphospace representing test architecture was used to describe morphological evolution in terms of total variance and total range. Discordances between disparity and diversity were evident and were expressed both as deceleration in morphological diversification in all groups and as disproportionately higher disparity early in the histories of the Atelostomata, Holasteroida, and Spatangoida. The finding that the early atelostomate disparity peak coincides with the origin of the orders Holasteroida and Spatangoida lends support to the perception of orders as semi-independent entities in the biological hierarchy and as meaningful proxies for morphological distinctness. A comparison of holasteroid and spatangoid responses to the end-Cretaceous mass extinction revealed morphological selectivity. Paleocene spatangoid survivors showed no change in disparity relative to the Campanian-Maastrichtian sample, suggesting nonselectivity. Holasteroids suffered a pronounced loss in disparity (despite a rather high Late Cretaceous level of disparity), indicating morphological selectivity of extinction. Partitioning of disparity into plastral and nonplastral components, reflecting different degrees of developmental entrenchment and functionality, suggests that the origin of holasteroids and spatangoids is more consistent with an exploration of the developmental flexibility of nonplastral constructions than with uniform ecospace occupation. Within groups, several patterns were also most consistent with intrinsic controls. For plastral landmarks, there is an apparent increase in developmental modularity and decrease in developmental constraint from disasteroids to holasteroids and spatangoids. For nonplastral landmarks, no substantial change in disparity was observed from disasteroids to holasteroids and spatangoids, suggesting the maintenance of a developmental constraint despite the passage of time and ecological differentiation. More generally, this study suggests that certain topologies of disparity and evolutionary mechanisms potentially characteristic of the lower Paleozoic radiations of higher taxa (e.g., developmental flexibility) need not be confined to any given time period or hierarchical level.