The Collapse of International Trade During the 2008-2009 Crisis: In Search of the Smoking Gun

One of the most striking aspects of the recent recession is the collapse in international trade. This paper uses disaggregated quarterly and monthly data on U.S. imports and exports to shed light on the anatomy of this collapse. We find that the recent reduction in trade relative to overall economic activity is far larger than in previous downturns. Information on quantities and prices of both domestic absorption and imports reveals a more than 50% shortfall in imports, relative to what would be predicted by a simple import demand relationship. In a sample of imports and exports disaggregated at the 6-digit NAICS level, we find that sectors used as intermediate inputs experienced significantly higher percentage reductions in both imports and exports. We also find support for compositional effects: sectors with larger reductions in domestic output had larger drops in trade. By contrast, we find no support for the hypothesis that trade credit played a role in the recent trade collapse.2008-2009 Crisis, International Trade

The Role of Financial Factors in the Trade Collapse: A Skeptic's View

This paper explores the role of financial factors in the 2008-9 collapse of U.S. imports and exports. Using highly disaggregated international trade data, we examine whether the cross-sectoral variation in how much imports or exports fell during this episode can be explained by financial variables. To do this, we employ a wide variety of possible indicators, such as standard measures of trade credit and external finance dependence, proxies for shipping lags at the sector level, and shares of intra-firm trade in each sector. Overall, there is very little evidence that financial factors played a role in the collapse of U.S. trade.2008-2009 Crisis, International Trade, Financial Factors

Social Media and Journalism: 10 Years Later, Untangling Key Assumptions

Amid a broader reckoning about the role of social media in public life, this article argues that the same scrutiny can be applied to the journalism studies field and its approaches to examining social media. A decade later, what hath such research wrought? We need a more particular accounting of the assumptions, biases, and blind spots that have crept into this line of research as well as the study of mediated conversations broadly. Our purpose is to provoke reflection and chart a path for future research by critiquing themes of what has come before. In particular, we seek to untangle three faulty assumptions—often implicit but no less influential—that have been overlooked in the rapid take-up of social media as a key phenomenon for journalism studies particularly and digital media studies generally: (1) that social media would be a net positive; (2) that social media reflects reality; and (3) that social media matters over and above other factors

The "Collapse in Quality" Hypothesis

This paper evaluates the hypothesis that during the 2008-2009 collapse in international trade, imports of higher quality goods experienced larger reductions compared to low-quality imports, using data on US imports disaggregated by HS-10 product category and source country. We find little, if any, robust econometric evidence in support of this hypothesis.

The electrolytic refining of copper

Although copper can be separated from its solution by means of the electric current and the amount so separated varies directly as the current, there is a point in each and every solution where on account of the energy given off to the ions, the copper will be carried over in a more or less impure state, depending upon the strength of the current, the strength of the solution,whether it is saturated or only partly saturated, or whether normal basic or acid and also upon the amount of impurities in the solution. It is the purpose of this thesis (1) With a neutral solution of CuSO₄, varying in strength from a one-fourth saturated to a saturated solution, to find the strength of current at which the oxide of copper will be deposited on the cathodes. (2) With solution of same strength but varying the amount of H₂SO₄ from 1 to 10 cc, to find the strength of current necessary to deposit copper oxide. (III) To find the effect of lead, arsenic, antimony, bismuth and tin on the deposited copper --Introduction, page 1

In-Context Policy Iteration

This work presents In-Context Policy Iteration, an algorithm for performing Reinforcement Learning (RL), in-context, using foundation models. While the application of foundation models to RL has received considerable attention, most approaches rely on either (1) the curation of expert demonstrations (either through manual design or task-specific pretraining) or (2) adaptation to the task of interest using gradient methods (either fine-tuning or training of adapter layers). Both of these techniques have drawbacks. Collecting demonstrations is labor-intensive, and algorithms that rely on them do not outperform the experts from which the demonstrations were derived. All gradient techniques are inherently slow, sacrificing the "few-shot" quality that made in-context learning attractive to begin with. In this work, we present an algorithm, ICPI, that learns to perform RL tasks without expert demonstrations or gradients. Instead we present a policy-iteration method in which the prompt content is the entire locus of learning. ICPI iteratively updates the contents of the prompt from which it derives its policy through trial-and-error interaction with an RL environment. In order to eliminate the role of in-weights learning (on which approaches like Decision Transformer rely heavily), we demonstrate our algorithm using Codex, a language model with no prior knowledge of the domains on which we evaluate it.Comment: 10 pages, 4 figures, submitted to ICLR 202

Circular 64

Treatment of Alaska-produced food products by ionizing radiation may benefit the seafood and agricultural industries and the Alaskan consumer. A feasibility study to evaluate the potential social and economic benefits and risks as well as the costs of using the process in Alaska on Alaskan products is being coordinated by the Institute of Northern Engineering. A research and development project to determine effects on the quality o f Alaskan products could be the next phase in the introduction o f a new food-preservation technique to Alaska

Essays on the Macroeconomics of Trade Flows.

Many macroeconomic forces affect international trade. These include nominal uncertainty, exchange rate movements, and each country's business cycle. This dissertation consists of three essays which explore the impact of these macroeconomic forces. In the first chapter, I consider the choice firms face between serving a foreign market through exports or producing abroad as a multinational. They face volatile nominal conditions in the foreign market, and I show how rising volatility shifts firms away from multinational production towards exporting. Exporting firms gain a greater advantage from foreign contractions because their goods become relatively cheaper in foreign currency terms. I use U.S. trade and multinational sales data and show that in countries with greater inflation volatility, we observe a higher proportion of exports. In the second chapter, I examine whether our improved understanding of international price setting helps to explain international trade flows themselves when subject to exchange rate shocks. While menu cost models with strategic complementarities are capable of matching the observed characteristics of international prices, I find that they still perform relatively poorly in explaining trade flows. This class of models, despite having fairly low short-run pass-through to import prices, still implies a large trade value response to exchange rate changes. Furthermore, sectors with more flexible prices or more substitutable goods respond very similarly to those with stickier prices or less substitutable goods, contrary to the implications of the model. Finally, in joint work with Andrei Levchenko and Linda Tesar, the third chapter studies the collapse of international trade during 2008-2009. We show how the composition of trade is important for understanding why it is so much more volatile over the business cycle. The U.S. trades disproportionately in sectors where domestic production or consumption also dropped significantly, like durable consumption and capital goods. On the other hand, we find no evidence for other commonly cited factors, like credit conditions or inventories.Ph.D.EconomicsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/86285/1/ltlewis_1.pd

Measuring sediment transport rates using tracer gravel and RFID technology

Rates of sediment transport were determined using tracer gravel and a RFID antenna array at Oak Creek (Oregon) to compare a new method with an existing transport relation created from data previously collected in the same study reach. Close to 3,000 tracers were deployed throughout the study reach and were composed of particles from four different class sizes, including 11–16 mm, 16–32 mm, 32–64 mm, and 64–101.5 mm. Tracer positions were monitored between 2016–2022 using three antennas, stretching across the stream channel, on the bed of the stream and a handheld antenna was used to locate tracer positions between antennas and downstream of the array. Transport rates were calculated from inter-arrival times of pairs of tracers moving in and out of the readable range of an antenna. Results showed that for any given discharge, transport rates for tracer gravel were lower than what was expected from the other transport relation for the reach. Specifically, the smaller two size classes displayed transport rates lower by an order of magnitude or greater than what was expected, while the larger two sizes classes produced rates inside of an order of magnitude lower. Several problems with the methodology presented themselves over the course of data collection but did not affect the quality of the data gathered. Results from this study build on a plethora of previous work using tracer particles over the last few decades and this methodology has the potential to be used more widely and on larger stream systems