Peer-reviewed Papers

Woodill, A. J., Kavanaugh, M., Harte, M., & Watson, J. R. (2021). Ocean seascapes predict distant‐water fishing vessel incursions into

      exclusive economic zones. Fish and Fisheries. [link]

Woodill, A. J., Nakamoto, S. T., Kawabata, A. M., & Arita, S., Leung, P. (2021). Optimal spraying strategy to combat the coffee berry borer:

      A dynamic approach. Journal of Food and Agriculture Research. [link]

Woodill, A. J., Nakamoto, S. T., Kawabata, A. M., & Arita, S., Leung, P. (2019). The Impact of CBB on the Economics of Coffee Production in Hawai‘i:

      2007–2012 USDA Census Analysis. (May), 1-12 Insect Pests. [link]

Woodill, A. J., Nakamoto, S. T., Kawabata, A. M., & Leung, P. (2017). To Spray or Not to Spray: A Decision Analysis of Coffee Berry Borer in Hawaii.

      Insects, 8(4), 116. [link]

Woodill, A. J., Hemachandra, D., Nakamoto, S. T., & Leung, P. (2014). The Economics of Coffee Production in Hawai’i, (June),1-9. [link]

Richardson, G. M., Bowers, J., Woodill, A. J., Barr, J. R., Gawron, J. M., & Levine, R. a. (2014). Topic Models: A Tutorial with R. International Journal

      of Semantic Computing, 08(01), 85-98. [link]


Watson, J. R., Woodill, A. J., Kavanaugh, M. “An Operational Forecasting System Based On Anomalous Behaviors In Complex Systems.”

      U.S. Patent Application No. 63/027,651 May 20, 2020.

Working Papers

Anticipating Illegal Maritime Activities from Anomalous Multiscale Fleet Behaviors (Under Review)

James R. Watson and A. John Woodill

Illegal fishing is prevalent throughout the world and heavily impacts the health of our oceans, the sustainability and profitability of fisheries, and even acts to destabilize geopolitical relations. To achieve the United Nations’ Sustainable Development Goal of “Life Below Water”, our ability to detect and predict illegal fishing must improve. Recent advances have been made through the use of vessel location data, however, most analyses to date focus on anomalous spatial behaviors of vessels one at a time. To improve predictions, we develop a method inspired by complex systems theory to monitor the anomalous multi-scale behavior of whole fleets as they respond to nearby illegal activities. Specifically, we analyze changes in the multiscale geospatial organization of fishing fleets operating on the Patagonia Shelf, an important fishing region with chronic exposure to illegal fishing. We show that legally operating (and visible) vessels respond anomalously to nearby illegal activities (by vessels that are difficult to detect). Indeed, precursor behaviors are identified, suggesting a path towards pre-empting illegal activities. This approach offers a promising step towards a global system for detecting, predicting and deterring illegal activities at sea in near real-time. Doing so will be a big step forward to achieving sustainable life underwater.

Adaptation and Nonlinear Temperature Effects: Second-Order Impacts of Climate Change that Cancel (In preparation)

A. John Woodill and Michael J. Roberts

A common theme in the economics of climate change is that farmers will adapt by planting different crops and adjusting other inputs, thereby offsetting negative impacts and further exploiting beneficial changes to climate. Many have suggested that adaptation is central to mitigating these negative impacts of climate change. However, measuring adaptation is difficult due to a variety of factors, such as responses to prices, institutional incentives, and technological progress. It is well-established that nonlinear (second-order) temperature effects are negative, but little is known about the effect size of adaptation. Basic microeconomic theory (the envelope theorem) suggests that adjustments in choices ought to be second-order relative to the direct effect of climate holding choices fixed. Using this framework, we use continuous crop-choice changes at the US county-level to estimate a first-order effect without adaptation and nonlinear effects with and without adaptation. We examine the distributions of crop choices over climate and consider the size of the positive second-order effects that may be gleaned from adaptation in relation to the negative second-order temperature effects from climate change. Our empirical results show that second-order effects with adaptation are similar to first order effects without adaptation, a direct result of the envelope theorem. We then show that aggregating over a continuum of climates produces countervailing positive and negative second-order effects that approximately cancel. Therefore, reasonably accurate climate change impacts can be discerned by aggregating local marginal effects of weather across the current distribution of activities and climates. These results suggest estimating local marginal effects, while holding choices fixed, can provide a more accurate assessment of climate change impacts without the need to estimate adaptation directly.

Adaptation to Climate Change: Disentangling Revenue and Crop Choice Responses (In preparation)

A. John Woodill and Michael J. Roberts

Adaptation by crop-switching has been suggested as a way to mitigate the harmfull effects of climate change on agriculture. Empirically, long run impact studies focus on cross-sectional associ- ations between agricultural outcomes and prevailing climate, implicitly accounting for adaptation; but the adaptive mechanism is not clear and the relationships may be confounded by unobserved factors. In this paper, we use a long history of crop choice and productivity outcomes to estimate effects of both weather and climate for major field crops in the United States. The approach lever- ages historical differences in climate trends across U.S. counties, differences that are large enough to span anticipated climate changes over the next 50 years, even after removing state-level trends. Climates are defined by backward-looking rolling means of the weather measures, with lag length selected via cross-validation. We then estimate the effect of climate change from a base level to uniform increases in temperature from 0-5°C. We find adaptation slightly reduces impacts relative to estimates that consider weather alone.

Preminary Analysis

Quantifying the Impact of Conflict and Cooperation on Fisheries in Puerto Rico

A. John Woodill, Nico Gomez, Ciera Villegas, and James R. Watson

The Value of Oceanographic Seascapes

A. John Woodill, Maria Kavanaugh, Michael Harte, and James R. Watson

Fisheries Alpha-diversity and Climate Change Impacts

A. John Woodill, Maria Kavanaugh, and James R. Watson

The Endless Summer: Harmful Alga Blooms and Climate Change

James R. Watson and A. John Woodill