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This dissertation studies the impact of data revisions on macroeconomic expectations. In the first chapter I show theoretically how revised data bias estimates of information frictions taken from surveys of expectations. The bias is due to the dynamic property of revised data which introduces additional past dependency into forecasts, breaking the informational symmetry between forecast errors and forecast updates. I propose a new estimation specification which corrects the bias and apply my method to data from the Survey of Professional Forecasters. I find the degree of information frictions is 33% different from existing estimates on average. Using my new estimates, I find equilibrium models of incomplete information more closely match the data. In the second chapter, I study socially optimal data provision when the economy resembles a beauty-contest. The budget-constrained statistical office (S.O.) faces a trade-off: provide imprecise yet timely data about the present, or wait to provide more precise yet delayed data about the past. I find the S.O.’s welfare-maximizing choice of current versus revised signal precisions depends on the accuracy of private information and strength of strategic incentives. In some cases the S.O. offers a mixture of both signals, while in others it provides only one or neither signal in order to reduce the crowding-out of private information caused by the coordination incentive. The S.O. treats the revised signal as an inferior good, reducing its precision in favor of the current signal when the budget limit rises. In the third chapter, I evaluate the interaction between revised data and higher-order dynamics when estimating information frictions. I prove analytically that the existing estimation method is valid when the fundamental possesses additional past dependency relative to the case in chapter one. I find additional bias terms in estimates of information frictions in the presence of revised data and higher-order dynamics. I propose a correction which eliminates the bias and does not depend on the specific time series properties of the data. I use simulation to study the nature of this new bias, finding it to be quantitatively small relative to the bias caused solely by revised data.

Topics associated with the biological sciences form a significant fraction of the curriculum in science at primary school level in the U.K. In this methodology paper we demonstrate how a wide range...

We show that the `optimal' use of the parallel composition theorem corresponds to finding the size of the largest subset of queries that `overlap' on the data domain, a quantity we call the \emph{maximum overlap} of the queries. It has previously been shown that a certain instance of this problem, formulated in terms of determining the sensitivity of the queries, is NP-hard, but also that it is possible to use graph-theoretic algorithms, such as finding the maximum clique, to approximate query sensitivity. In this paper, we consider a significant generalization of the aforementioned instance which encompasses both a wider range of differentially private mechanisms and a broader class of queries. We show that for a particular class of predicate queries, determining if they are disjoint can be done in time polynomial in the number of attributes. For this class, we show that the maximum overlap problem remains NP-hard as a function of the number of queries. However, we show that efficient approximate solutions exist by relating maximum overlap to the clique and chromatic numbers of a certain graph determined by the queries. The link to chromatic number allows us to use more efficient approximate algorithms, which cannot be done for the clique number as it may underestimate the privacy budget. Our approach is defined in the general setting of $f$-differential privacy, which subsumes standard pure differential privacy and Gaussian differential privacy. We prove the parallel composition theorem for $f$-differential privacy. We evaluate our approach on synthetic and real-world data sets of queries. We show that the approach can scale to large domain sizes (up to $10^{20000}$), and that its application can reduce the noise added to query answers by up to 60\%., This is the full version of the paper with the same title to appear in the proceedings on the 22nd Privacy Enhancing Technologies Symposium (PETS 2022)

Recently, the development of autonomous vehicles and intelligent driver assistance systems has drawn a significant amount of attention from the general public. One of the most critical issues in the development of autonomous vehicles and driver assistance systems is their poor performance under adverse weather conditions, such as rain, snow, fog, and hail. However, no current study provides a systematic and unified review of the effect that weather has on the various types of sensors used in autonomous vehicles. In this article, we first present a literature review about the impact of adverse weather conditions on state-ofthe-art sensors, such as lidar, GPS, camera, and radar. Then, we characterize the effect of rainfall on millimeter-wave (mmwave) radar, which considers both the rain attenuation and the backscatter effects. Our simulation results show that the detection range of mm-wave radar can be reduced by up to 45% under severe rainfall conditions. Moreover, the rain backscatter effect is significantly different for targets with different radar cross-section (RCS) areas.

The greater than 109 km3 volume of the deep-sea water column and greater than 300 × 106 km2 area of the deep-sea floor represent a major natural capital asset. Global society has been utilising space in the deep ocean as a reservoir for solid, liquid, and hazardous waste produced by terrestrial-based societies, as a buffer that absorbs nonsolid, nonliquid industrial waste streams, specifically CO2 from fossil fuel and biomass burning, heat from a warming atmosphere, and as freely available and convenient space. High-value uses such as the deployment of transoceanic telecommunications cables provide substantial, near-term economic and societal returns with minimal environmental impact. Low-value uses of this natural capital as empty space to absorb waste have arguably enabled industrialisation to continue further along an unsustainable trajectory than would have occurred had there been no such waste buffer available.

The first indication, other than mythological, that animals occurred in the deep sea was the serendipitous recovery of the euryalid brittlestar Astrophyton linki on a sounding line cast to 1800 m in the Baffin Sea in 1818.1 The early 19th century saw an increasing interest in marine organisms in sha...

Man has lived in the presence of electric fields for many centuries most of which predate the invention of the electrical generator. Current theory, as well as history, tells us that early man recognized that he had no control over lighting and that magnetic mineral ore, lodestone, did not appear to have any biological effect. However, contact with the fish, Torpedo which inhabits the Mediterranean, could produce shocking results when in contact with the body. The biological effects of the Torpedo fish were described by Plato, Aristotle and many others in ancient Greek and Roman texts. The first medical use of electric fish is found in a report by S. Largus in the first century.22 Prior to the Renaissance, electric fish were used by Arab physicians to treat sleeping disorders,37 migraine, melancholy and epilepsy.50 This use of electric fish represents an ancient precursor of electroshock therapy for severe depression. The ancient physicians did not recognize that these fish were producing an electrical current, rather the cure was thought to result from some excretion of a semi-material nature. It was recognized, however, that the electric fish had to be alive to produce any beneficial effects. Thus, therapy was limited to sites near the seashore where fish could be caught and maintained fresh and alive until used for treatment.

Nothing has been accomplished as yet in the preparation of tests for the field of social sciences as a whole. So far as one is able to learn, progress has been made in only one part of the field, namely, history. One is able to find 22 tests or scales for history in secondary schools, prepared by 16 different agencies. Of these 22 tests, 2 are for use in the field of ancient history, 15 for American history, and 5 for the testing of general ability in history. At the time of writing, 13 are known to be available for use in prepared forms. The most general criticism that can be passed upon the group as a whole is the fact that 15 tests, or more than half, aim to test only one ability, that is, are only informational in character. These tests have, therefore, not kept pace with the newer methods of teaching in the field of history. Teachers in increasing num bers are coming to recognize that historical information per se is but a means and not an end. It is only too well known, as results have shown, that pupils do not retain much historical information. Bell and McCollum have shown experimentally that "simple questions on fundamental aspects" of United States history are answered 33 percent correctly by high-school pupils.1 There are other abilities to be tested in history, which, in the minds of progressives, are of greater value. History, in so far as the measurement of results is concerned, is "unlike the more objective studies. It has been difficult to de termine a test satisfactory to any great number. Even in the field of information alone agreement is difficult, for the field is unlimited in extent. Content vital to one course of study may not be thought so for another. The recent shift of emphasis, evident in texts, has interrupted any progress that may have been

The sublittoral benthic community structure in Oxwich Bay (South Wales, Gower coast) is more closely related to the hydrodynamic regime of the bay than to the nature of the sediment-types which form the seabed. The sediments are both glacial and post-glacial in origin, and are undergoing redistribution and sorting according to the magnitude and direction of near-bed current-velocities and wave-orbital velocities to which they are exposed. Many seabed sediments are therefore not in equilibrium with the present hydrodynamic regime. However, the distribution of meroplanktonic larvae and newly metamorphosed adults is directly influenced by the hydrodynamic environment: there is an anticlockwise tidal gyre, during both flood and ebb, and the area of its centre is protected from the prevailing southwesterly, long-wavelength swell by refraction around Oxwich Point. Centripetal motion transports larvae to the centre of the gyre, where relatively low current velocities and low eddy viscosity values permit settlement. After settlement, the adult distribution pattern depends on the degree of migratory activity. Burrowing species (e.g. Syndosmya ( Abra ) alba , Cultellus pellucidus ) have a distribution closely related to the hydrodynamic environment, but this relationship becomes obscured in errant species (e.g. Ophiura albida ) by migration after settlement has occurred. Errant species within a community aid its development by feeding on the larvae of possible predators of the dominant species of that community.

During the European Commission's Framework Six Programme, HERMES, we investigated three main areas along the European margin, each characterized by the presence of seep-related structures exhibiting different intensity of activity and biological diversity. These areas are: (1) the Nordic margin with the Hakon Mosby mud volcano and many pockmarks, (2) the Gulf of Cadiz, and (3) the eastern Mediterranean with its hundreds of mud volcanoes and brine pool structures. One of the main goals of the HERMES project was to unravel the biodiversity associated with these seep-associated ecosystems, and to understand their driving forces and functions, using an integrated approach. Several multidisciplinary research cruises to these three areas provided evidence of high variability in ecosystem processes and associated biodiversity at different spatial scales, illustrating the "hotspot" nature of these deep water systems. HERMES (EC) - GOCE-CT-2005-511234