Empirical Evidence on the Role of Non Linear Wholesale Pricing and Vertical Restraints on Cost Pass-Through

How a cost shock is passed through into final consumer prices may relate to nom-inal price stickiness and rigidities, the existence of non adjustable cost components, strategic mark-up adjustments, or other contract terms along the supply distribution chain. This paper presents a simple framework to assess the potential role of non linear pricing contracts and vertical restraints such as resale price maintenance or wholesale price discrimination in the supply chain in explaining the degree of pass-through from upstream cost shocks in the ground coffee category to downstream retail prices. We do so in the German coffee market where both upstream and downstream firms make pricing decisions allowing for non linear pricing and vertical restraints. Using counter-factual simulations of an upstream coffee cost shock, we find that the existence of resale price maintenance between manufacturers and retailers increases pass through rate by more than 10 points relative to the case when this assumption is not allowed with non linear pricing or when double marginalization along the distribution chain is present. The intuition for our findings is that resale price maintenance restrictions make it less possible for retailers to perform strategic mark-up adjustments when faced with a cost shock. We also find that the larger the simulated cost shocks or the less concentrated upstream sector, and also when faced with less elastic demands, the larger the role of vertical restraints in preventing retailers to perform strategic mark-up adjustments, and thus the higher the pass-through increases

Synopsis of biological data on the pink shrimp, Pandalus borealis Kroyer, 1838

This synopsis of the literature was designed to summarize the biological and biochemical studies involving Pandalus borealis as well as to provide a summary of the literature regarding the fisheries data published before early 1984. Included are many unpublished observations, drawn from studies at the State of Maine Department of Marine Resources Laboratory in West Boothbay Harbor, Maine. (PDF file contains 63 pages.

Refining the climate, glacier, and volcanic history of Iceland during the Holocene

Iceland’s position at the confluence of major oceanic and atmospheric fronts results in a highly sensitive climate evident in both instrumental and paleo records. However, open questions still remain regarding the pre-instrumental evolution of climate, glacier, and volcanic activity at this hemispherically relevant location. This dissertation capitalizes on and merges a range of analytical techniques in an effort to refine our understanding of Icelandic climate variability, glacier extent, and tephrochronology during the Holocene epoch, with a focus on Northwest Iceland. In order to provide robust age control in our records, this research required the development of a tephrochronological framework for West Iceland, a region that lacks the otherwise widely-dispersed rhyolitic marker tephras. Glacier proxies (threshold lake sediment records and emerging dead vegetation from receding ice margins) provide firm constraints on the Holocene activity of Drangajökull, an ice cap in northwest Iceland, and high-resolution lake sediment proxy records (TOC, δ13C, C/N and biogenic silica) collected adjacent to the glacier elucidate the concomitant climate. Furthermore, we explore two lipid biomarker paleothermometers (alkenones and branched glycerol dialkyl glycerol tetraether, GDGTs) in one of these lakes and its catchment soils for the first time in Iceland to quantify the evolution of Holocene summer temperature. Similar to other Icelandic ice cap histories, our records collectively illustrate that a warm early Holocene (2 to 5 oC above modern) likely resulted in the complete demise of Drangajökull shortly after 9 ka. Subsequent to peak early Holocene summer warmth, lake sediment climate proxies indicate punctuated declines in algal productivity and increases in soil erosion alongside steadily decreasing northern hemisphere (NH) summer insolation. As summers continued to cool, Drangajökull re-nucleated by ~2.3 ka and episodically expanded to its maximum dimension during the Little Ice Age (0.7-0.1 ka), when summer temperatures are estimated to be ~1 oC below modern. Triggers for cold anomalies are linked to variable combinations of freshwater pulses from waning Pleistocene ice sheets, low total solar irradiance, explosive and effusive volcanism, and internal modes of climate variability, with cooling likely sustained by ocean/sea-ice feedbacks. In addition to the lake record, GDGTs were also applied in two other settings: a Holocene soil archive in central Iceland and in the marine realm along the North Iceland Shelf. For the latter, we also developed an Icelandic GDGT-temperature calibration based on marine surface sediment that highlights the reduced uncertainty (± 0.4 oC) achievable for local rather than global calibrations (e.g., ± 4.0 oC). Local calibrations are particularly important for areas where the temperature relationship of GDGTs deviates from the overall linear correlation observed in global calibrations (i.e., cold and warm regions), such as Iceland. Although clearly reflected in the maximum dimensions of Drangajökull, the Little Ice Age cooling is obscured in all lake, soil and marine organic geochemical records investigated in this dissertation. For the former two, the erosion of older soils, nutrients and relic GDGTs likely compromise the records and imply warmth. On the other hand, the development of thick sea ice inferred from highly branched isoprenoid biomarkers on the North Iceland Shelf insulated the subsurface waters during the peak Little Ice Age, likely preventing the ventilation of heat from below the surface layer to the atmosphere. This dissertation provides critical and nuanced observations necessary for evaluating modeling simulations aiming to forecast the poorly constrained climate of the coming century.Næmni Íslands fyrir veðurfarsbreytingum kemur fram í samfelldum veðurathugunum og veðurvísum og skýrist að einhverju leyti af stöðu landsins á skilum kaldra og tempraðra sjávar- og loftmassa, sem færast í takt við umhverfisbreytingar á Norður Atlantshafi. Samspil og þróun loftslags, jökla og eldvirkni fyrir tíma samfelldra mælinga er margslungið og margt er enn á huldu um hvernig orsakasamhengi er háttað. Mikilvægt er að rýna betur í þessa ferla til að unnt verði að bæta spár um komandi umhverfis- og veðurfarsbreytingar. Þessi ritgerð greinir frá rannsóknum þar sem fjölþættum greiningaraðferðum er beitt í því skyni að betrumbæta skilning okkar á loftslagsbreytingum, útbreiðslu jökla og myndun gjóskulaga á Íslandi á Nútíma, með áherslu á Vestfirði og Drangajökul. Nákvæm greining á gjóskulögum, sem er að finna í seti vatna sem liggja að Drangajökli, var gerð til að ná fram áreiðanlegum aldursgreiningum á vatnasetinu og veðurvísum sem í því finnast, en þetta svæði hefur skort nákvæmt gjóskutímatal hingað til. Vitnisburður jökulframrása (stöðuvatnaset og aldursgreiningar á gróðri sem hefur komið í ljós undan hörfandi jökli) hafa að geyma nákvæm gögn um virkni Drangajökuls á Nútíma, studdur af veðurvísum (TOC, δ13C, C/N og lífrænn kísill) sem finnast í seti stöðuvatnanna. Að auki var með þessu verkefni í fyrsta skipti á Íslandi beitt rannsóknum á tveimur hitastigs- og rakanæmum lífmerkjum (alkenones and branched glycerol dialkyl glycerol tetraether, GDGTs) í seti eins stöðuvatnsins og í jarðvegssniði sem er að finna á upptakasvæði þess, í þeim tilgangi að ná fram þróun magnbundins sumarhita á Nútíma. Svipað og rannsóknir á sögu og þróun annarra íslenskra jökla gefa til kynna, benda niðurstöður okkar til þess að hlýindi árla á Nútíma (á bilinu 2° til 5 °C yfir meðaltali síðustu áratuga) hafi leitt til hörfunar á forvera Drangajökuls. Fljótlega eftir að hámarki hlýnunar var náð, snemma á Nútíma, sýna veðurvísar í stöðuvatnaseti stigvaxandi hnignun í framleiðni vatnaþörunga og aukningu í jarðvegsrofi, sem svörun við hægfara lækkun sumarinngeislunar á norðurhveli jarðar. Drangajökull myndaðist á ný fyrir um 2300 árum, samhliða því að sumur tóku að kólna, og náði jökullinn hámarksútbreiðslu á litlu ísöldinni (fyrir 0,7-0,1 þúsund árum) þegar hitastig sumars er talið hafa verið ~1 °C undir meðalhita síðustu áratuga. Ástæður kaldra frávika á þessu tímabili eru tengdar minni sólarvirkni, aukinni eldvirkni (bæði sprengigosa og hraungosa) og innri breytileika veðurkerfa þar sem kólnun var viðhaldið af svörun hafs og hafíss. Hitastigs- og rakanæma lífmerkið GDGT var að auki rannsakað í tveimur öðrum umhverfum; í jarðvegssniði frá Nútíma á hálendi Íslands, og í sjávarsetkjarna sem tekinn var af landgrunninu fyrir norðan Ísland. Fyrir sjávarsetskjarnann var að auki þróaður íslenskur GDGT-hitastigskvarði, sem byggir á yfirborðssýnum teknum af sjávarbotninum og sýna niðurstöður möguleika á að ná fram minni óvissu (±0,4 °C) með slíkri staðbundinni kvörðun samanborið við hnattræna kvörðun (±4,0 °C). Staðbundin kvörðun er sérstaklega mikilvæg fyrir svæði eins og Ísland, þar sem hitastigstengsl GDGT víkur frá heildar línulegri fylgni hnattrænna kvarða (þ.e. köld og heit svæði). Þó kólnun á litlu ísöldinni endurspeglist greinilega í hámarksstærð Drangajökuls og eðlisrænum veðurvísum, kemur kólnun Litlu ísaldarinnar ekki skýrt fram í hitastigsnæma lífmerkinu (GDGT) í þeim þremur umhverfum sem hér eru til umfjöllunar (vatnaseti, jarðvegi og sjávarseti). Í fyrstu tveim tilfellunum, (þ.e. vatnaseti og jarðvegssniði), er líklegasta ástæðan rof á eldri jarðvegi frá hlýrri tíma (þ.e eldri jarðvegur hefur fokið yfir yngri jarðveg og í stöðuvatnið á hámarki litlu ísaldar), næringarefni og GDGT hafa blandast yngra efni að einhverju leyti og gefa því til kynna hlýrra hitastig en var í raun á litlu ísöldinni. Í sjávarsetinu benda lífmerkin til þess að þykkur og samfelldur hafís hafi myndast á hámarki litlu ísaldarinnar og náð að einangra sjó undir yfirborðinu og þannig komið í veg fyrir hitastreymi frá undirlögum sjávar til andrúmsloftsins. Þessi ritgerð bætir við nýjum og ítarlegum niðurstöðum sem eru mikilvægar fyrir gerð líkana sem miða að því að spá fyrir um þróun loftslags og hugsanlegar breytingar á næstu öldum.RANNIS, University of Iceland, University of Colorado Boulder, Lamont-Doherty Earth Observator

Morpho-tectonic analysis of the East African Rift System

Tectonic uplift of mountain ranges and plateaus have a significant impact on the geological record by influencing drainage systems and sediment supply, and on climate and on biogeography. Recent geomorphological, geochronological and geophysical studies have provided some understanding of time constraints and uplift rate distribution patterns, especially in convergent plate margins. Nevertheless, fewer studies took a comprehensive view over the topographic patterns, rates and changes in rates of tectonic uplift in continental rift systems. We do not know the how ground’s vertical motion is localized along the axis of rift and the relative roles of upwelling of magma and rift extensional processes play in tectonic uplift history. The East African Rift System (EARS) has long served as the ideal example of a continental rift to explore the distribution patterns, rates, and timing of tectonic uplift in the evolution of geomorphology. This work addresses fundamental questions of tectonic uplift and its footprint on the topography associated with rift systems. Specifically, three distinct segments along the EARS, the Rwenzori Mountains in the Western Branch, the southeastern Ethiopian Plateau in the Northern Branch and the Kenyan Rift in the Eastern Branch are investigated. The first chapter evaluated geomorphic proxies, including those obtained from bedrock streams (areal proxies including asymmetry factor (AF), mountain front sinuosity (Smf), hypsometric integral (HI), geophysical relief, and shape factor (Shp), and linear proxies including normalized steepness index (ksn), length-gradient index (SLk) and Chi gradient (Mχ)) in the Rwenzori Mountains, which represents an anomalously uplifted Precambrian horst within the western branch of the East African Rift system (EARS). This study aims to: (1) evaluate the usefulness of geomorphic proxies as recorders of drainage basin’s maturity and rock uplift rate; (2) evaluate the sensitivity of each geomorphic proxy to the drainage basin size and geometry, stream order, glaciers extent, and local structures; and (3) contribute to the understanding of morphotectonic evolution of the Rwenzori Mountains. For this, we computed the stream’s ‘Good of Fitness’ (R2, an indicator of the drainage basin’s maturity) and geomorphic proxies for the drainage basins and their streams in the Rwenzori Mountains from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) digital elevation model (DEM). Subsequently, we correlated the areal geomorphic proxies with each other and with R2. Also, we correlated the linear geomorphic proxies with each other and with published erosion rates obtained from cosmogenic 10Be analysis. Our results show that the areal geomorphic proxies (AF, Smf, HI, relief, and Shp), considering the drainage basin size and geometry, stream order, glacier extent, and local structures, can be applied to locally evaluate the maturity of the drainage basin. We also found that the linear geomorphic proxies (ksn, SLk, and Mχ) have strong positive correlation with the erosion rates, they are effective in detecting fault activities, and some of them (ksn and Mχ) are highly correlated with each other. Additionally, our geomorphic proxy results suggest that the north and south sectors of the Rwenzori Mountains are in relative tectonic quiescence but that the central sector is experiencing higher levels of erosion and rock uplift. The second chapter used morphotectonic analysis to study the tectonic uplift history of the southeastern Ethiopian Plateau (SEEP). Based on studies conducted on the Northwestern Ethiopian Plateau, steady-state and pulsed tectonic uplift models were proposed to explain the growth of the plateau since ~30 Ma. We test these two models for the largely unknown SEEP. We present the first quantitative morphotectonic study of the SEEP. First, in order to infer the spatial distribution of the tectonic uplift rates, we extract geomorphic proxies including normalized steepness index ksn, hypsometric integral HI, and chi integral χ from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) digital elevation model (DEM). Second, we compare these rates with the thickness of flood basalt that we estimated from geological maps. Third, to constrain the timing of regional tectonic uplift, we develop a knickpoint celerity model. Fourth, we compare our results to those from the Northwestern Ethiopian Plateau to suggest a possible mechanism to explain regional tectonic uplift of the entire Ethiopian Plateau. We find an increase in tectonic uplift rates from the southeastern escarpments of the Afar Depression in the northeast to that of the Main Ethiopian Rift to the southwest. We identify three regional tectonic uplift events at ~11.7, ~6.5, and ~4.5 Ma recorded by the development of regionally distributed knickpoints. This is in good agreement with ages of tectonic uplift events reported from the Northwestern Ethiopian Plateau. The third chapter examined the tectonic uplift history of the Kenya Rift (divided into a northern, a central, and a southern segment; henceforth NKR, CKR, and SKR) within the East African Rift System (EARS) by: (1) estimating the long-term (since Miocene - ~15 Ma) drainage incision pattern within the Kenya Rift by first obtaining the difference between modern topography and paleo-datum and then dividing the resulting regional incision by published ages of volcanic rocks; (2) characterizing the short-term (since Pliocene - ~4.5 Ma) drainage incision pattern and drainage basin divide migration using the chi integral geomorphic proxy; and (3) correlating the spatial and temporal drainage incision pattern with known magmatic, tectonic, and climatic events in the Kenya Rift. The long-term incision analysis shows that the incision rate is higher in the CKR averaging ~300 mm/ky since 4.5 Ma. Such Pliocene increase is also observed in other parts of the EARS. The short term incision analysis shows that the NKR is approaching steady state, while the CKR and SKR are still in transit state with active drainage basin divides migration. This work found that the spatial and temporal pattern of the tectonic uplift inferred from the drainage incision is well-correlated with known phases of magmatic activities. Also, this work found that the rapid increase in drainage incision since ~4.5 Ma correlated well with a major change in vegetation from grassland to woodland. This suggests that the tectonic uplift coupled with Pliocene magmatic activities have caused a major shift in the ecosystem in the region

Reinforcement Learning and Bandits for Speech and Language Processing: Tutorial, Review and Outlook

In recent years, reinforcement learning and bandits have transformed a wide range of real-world applications including healthcare, finance, recommendation systems, robotics, and last but not least, the speech and natural language processing. While most speech and language applications of reinforcement learning algorithms are centered around improving the training of deep neural networks with its flexible optimization properties, there are still many grounds to explore to utilize the benefits of reinforcement learning, such as its reward-driven adaptability, state representations, temporal structures and generalizability. In this survey, we present an overview of recent advancements of reinforcement learning and bandits, and discuss how they can be effectively employed to solve speech and natural language processing problems with models that are adaptive, interactive and scalable.Comment: To appear in Expert Systems with Applications. Accompanying INTERSPEECH 2022 Tutorial on the same topic. Including latest advancements in large language models (LLMs

Defying distance? The provision of services in the digital age

Digital platforms are transforming services by making the physical distance between provider and user less relevant. I quantify the potential gains this flexibility offers in the context of digital primary care in Sweden, harnessing nationwide conditional random assignment between 200,000 patients and 150 doctors. I evaluate causal effects of matching patients of varying risks to doctors with different skills and assess counterfactual policies compared to random assignment. Matching patients at high risk of avoidable hospitalizations to doctors skilled at triaging reduces avoidable hospitalizations by 20% on aggregate - without affecting other adverse outcomes, such as counter-guideline antibiotics prescriptions. Conversely, matching the best triaging doctors to the richest patients leads to more avoidable hospitalizations, since the most vulnerable patients are often the poorest. Hence, remote matching can sever the link between local area income and service quality in favor of a needs-based assignment, improving the effectiveness and equity of service provision

Security and Privacy for Modern Wireless Communication Systems

The aim of this reprint focuses on the latest protocol research, software/hardware development and implementation, and system architecture design in addressing emerging security and privacy issues for modern wireless communication networks. Relevant topics include, but are not limited to, the following: deep-learning-based security and privacy design; covert communications; information-theoretical foundations for advanced security and privacy techniques; lightweight cryptography for power constrained networks; physical layer key generation; prototypes and testbeds for security and privacy solutions; encryption and decryption algorithm for low-latency constrained networks; security protocols for modern wireless communication networks; network intrusion detection; physical layer design with security consideration; anonymity in data transmission; vulnerabilities in security and privacy in modern wireless communication networks; challenges of security and privacy in node–edge–cloud computation; security and privacy design for low-power wide-area IoT networks; security and privacy design for vehicle networks; security and privacy design for underwater communications networks

Development of advanced methods for the simulation of the reacting mixture formation in internal combustion engines with the use of machine learning algorithms

Besides increasing the share of electric and hybrid vehicles, in order to comply with more stringent environmental protection limitations, in the mid-term the auto industry must improve the efficiency of the internal combustion engine and the well to wheel efficiency of the employed fuel. To achieve this target, a deeper knowledge of the phenomena that influence the mixture formation and the chemical reactions involving new synthetic fuel components is mandatory, but complex and time intensive to perform purely by experimentation. Therefore, numerical simulations play an important role in this development process, but their use can be effective only if they can be considered accurate enough to capture these variations. The most relevant models necessary for the simulation of the reacting mixture formation and successive chemical reactions have been investigated in the present work, with a critical approach, in order to provide instruments to define the most suitable approaches also in the industrial context, which is limited by time constraints and budget evaluations. To overcome these limitations, new methodologies have been developed to conjugate detailed and simplified modelling techniques for the phenomena involving chemical reactions and mixture formation in non-traditional conditions (e.g. water injection, biofuels etc.). Thanks to the large use of machine learning and deep learning algorithms, several applications have been revised or implemented, with the target of reducing the computing time of some traditional tasks by orders of magnitude. Finally, a complete workflow leveraging these new models has been defined and used for evaluating the effects of different surrogate formulations of the same experimental fuel on a proof-of-concept GDI engine model.Besides increasing the share of electric and hybrid vehicles, in order to comply with more stringent environmental protection limitations, in the mid-term the auto industry must improve the efficiency of the internal combustion engine and the well to wheel efficiency of the employed fuel. To achieve this target, a deeper knowledge of the phenomena that influence the mixture formation and the chemical reactions involving new synthetic fuel components is mandatory, but complex and time intensive to perform purely by experimentation. Therefore, numerical simulations play an important role in this development process, but their use can be effective only if they can be considered accurate enough to capture these variations. The most relevant models necessary for the simulation of the reacting mixture formation and successive chemical reactions have been investigated in the present work, with a critical approach, in order to provide instruments to define the most suitable approaches also in the industrial context, which is limited by time constraints and budget evaluations. To overcome these limitations, new methodologies have been developed to conjugate detailed and simplified modelling techniques for the phenomena involving chemical reactions and mixture formation in non-traditional conditions (e.g. water injection, biofuels etc.). Thanks to the large use of machine learning and deep learning algorithms, several applications have been revised or implemented, with the target of reducing the computing time of some traditional tasks by orders of magnitude. Finally, a complete workflow leveraging these new models has been defined and used for evaluating the effects of different surrogate formulations of the same experimental fuel on a proof-of-concept GDI engine model

Alfven: magnetosphere-ionosphere connection explorers

The aurorae are dynamic, luminous displays that grace the night skies of Earth’s high latitude regions. The solar wind emanating from the Sun is their ultimate energy source, but the chain of plasma physical processes leading to auroral displays is complex. The special conditions at the interface between the solar wind-driven magnetosphere and the ionospheric environment at the top of Earth’s atmosphere play a central role. In this Auroral Acceleration Region (AAR) persistent electric fields directed along the magnetic field accelerate magnetospheric electrons to the high energies needed to excite luminosity when they hit the atmosphere. The “ideal magnetohydrodynamics” description of space plasmas which is useful in much of the magnetosphere cannot be used to understand the AAR. The AAR has been studied by a small number of single spacecraft missions which revealed an environment rich in wave-particle interactions, plasma turbulence, and nonlinear acceleration processes, acting on a variety of spatio-temporal scales. The pioneering 4-spacecraft Cluster magnetospheric research mission is now fortuitously visiting the AAR, but its particle instruments are too slow to allow resolve many of the key plasma physics phenomena. The Alfvén concept is designed specifically to take the next step in studying the aurora, by making the crucial high-time resolution, multi-scale measurements in the AAR, needed to address the key science questions of auroral plasma physics. The new knowledge that the mission will produce will find application in studies of the Sun, the processes that accelerate the solar wind and that produce aurora on other planet