Stochastic Forecasts of the Social Security Trust Fund

We present stochastic forecasts of the Social Security trust fund by modeling key demographic and economic variables as historical time series, and using the fitted models to generate computer simulations of future fund performance. We evaluate several plans for achieving long-term solvency by raising the normal retirement age (NRA), increasing taxes, or investing some portion of the fund in the stock market. Stochastic population trajectories by age and sex are generated using the Lee-Carter and Lee- Tuljapurkar mortality and fertility models. Interest rates, wage growth and equities returns are modeled as vector autoregressive processes. With the exception of mortality, central tendencies are constrained to the Intermediate assumptions of the 2002 Trustees Report. Combining population forecasts with forecasted per-capita tax and benefit profiles by age and sex, we obtain inflows to and outflows from the fund over time, resulting in stochastic fund trajectories and distributions. Under current legislation, we estimate the chance of insolvency by 2038 to be 50%, although the expected fund balance stays positive until 2041. An immediate 2% increase in the payroll tax rate from 12.4% to 14.4% sustains a positive expected fund balance until 2078, with a 50% chance of solvency through 2064. Investing 60% of the fund in the S&P 500 by 2015 keeps the expected fund balance positive until 2060, with a 50% chance of solvency through 2042. An increase in the NRA to age 69 by 2024 keeps the expected fund balance positive until 2047, with a 50% chance of solvency through 2041. A combination of raising the payroll tax to 13.4%, increasing the NRA to 69 by 2024, and investing 25% of the fund in equities by 2015 keeps the expected fund balance positive past 2101 with a 50% chance of solvency through 2077.

Insights from Industry Leaders: A Maturity Model for Strengthening Communication Measurement and Evaluation

Much scholarship has been devoted to identifying barriers that prevent the advancement of communication measurement and evaluation. This research focuses on the characteristics, objectives, and practices of chief communication officers (CCOs) with successful measurement and evaluation programs. Three key dimensions of practice emerged from in-depth interviews: communication executives’ measurement practices and evaluation programs were used to adjust communication strategies; were aligned with other business units; and were integrated with business priority plans. Interviewees also focused on the ability of communication measurement practices and evaluation programs to provide insights for executives, to align communication with the work of other business units, and to connect the organization with the outside environment and stakeholders. This study extends strategic communication scholarship by discussing how overcoming barriers and advancing measurement and evaluation work relates to roles adopted by organizational leaders. This article also offers a preliminary, scalable maturity model that aids in the development, formalization, and optimization of strategic communication measurement and evaluation. This study demonstrates the capacity for communication evaluation to overcome perceived barriers, realize appropriate stature with organizations, and grow communication functions accordingly

Climatic Influences of Deglacial Drainage Changes in Southern Canada at 10 to 8 ka Suggested by Pollen Evidence

Enhanced meltwater discharge from proglacial lakes Agassiz and Barlow-Ojibway at about 9.6 to 8.3 ka BP. created cold localized climates over downstream water bodies, specifically Lake Minong and Mattawa phase lakes in the Great Lakes and Goldthwait Sea in the Gulf of St. Lawrence. The cooling effect of the meltwater drainage suppressed summer warming of the surface lake waters, reduced the growing season and thus altered the vegetation composition in the surrounding land areas. The vegetation responded in different ways as evidenced by five variants from the normal pollen succession.The pollen anomalies are most pronounced where the effect of increased meltwater discharge had a strong influence, such as within or along the margins of Lake Agassiz, Mattawa phase lakes, and the Goldthwait Sea, or in their lee areas, especially where these water bodies intersected ecotonal boundaries. Climatic effects were minimal or non-existent where the water surface areas were restricted such as the channelized drainage routes of the Ottawa and St. Lawrence rivers. Diversion of Lakes Agassiz and Barlow-Ojibway drainage to Hudson Bay after about 8.4 ka BP reinstated summer warming of the surface water in the Great Lakes-St. Lawrence system bringing the 9.6-8.3 ka cool period to a close.L'augmentation du débit de l'eau de fonte provenant des lacs glaciaires Agassiz et Barlow-Ojibway de 9,6 à 8 ka BP a engendré des micro-climats froids au-dessus des nappes d'eau en aval : le Lac Minong, les lacs de la phase de Mattawa, dans les Grands Lacs, et la Mer de Goidtwaith, dans le golfe du Saint-Laurent. L'effet refroidissant du drainage de l'eau de fonte a entravé le réchauffement estival de la surface des eaux lacustres, écourté la saison végétative et ainsi modifié la composition de la végétation des terres environnantes. La réponse de la végétation a été variable comme l'indiquent les cinq types de déviation (anomalies polliniques) par rapport à la succession pollinique normale. Les anomalies sont plus importantes là où l'effet de l'augmentation du débit de l'eau de fonte a été plus prononcé, notamment près des limites des nappes d'eau touchés ou de leurs zones, surtout près des écotones. L'influence climatique a été très limitée ou nulle là où les surfaces aquifères étaient réduites, comme celles des cours de l'Outaouais et du Saint-Laurent. Le détournement de l'écoulement des lacs Agassiz et Barlow-Ojibway vers la mer d'Hudson après 8,4 ka BP a rétabli le réchauffement estival des eaux de surface du réseau des Grands Lacs et du Saint-Laurent, mettant ainsi fin à la période froide qui a prévalu de 9,6 à 8 ka.Der EinfluQ des Wechsels der Schmelzwassermenge aufdas Klima im sûdlichen Kanada um 10 bis 8 ka anhand von Pollenbelegen. Verstàrktes Schmelz-wasserabflieBen von den proglazialen Seen Agassiz und Barlow-Ojibway um etwa 9.6 bis 8.3 ka v.u.Z. bewirkte ôrtlich beschrànktes kaltes Klima ùber den Wasser-flàchen stromabwàrts, und zwar Minong-See und Seen der Mattawa-Phase in den GroRen Seen, und das Goldtwaith-Meer im Golf des Sankt Lorenz. Die kùhlende Wirkung des abflieBenden Schmelzwassers verhinderte die sommerliche Erwàrmung des Oberflàchenwassers der Seen, reduzierte die Wachstumsperiode und verànderte so die Zusammensetzung der Vegetation in den umliegenden Landgebieten. Die Vegetation reagierte auf verschiedene Weisen, wie aus fùnf Varianten der normalen Pollenabfolge ersichtlich wird. Die Pollen-Abweichungen sind am deutlichsten, wo die Wirkung des verstàrkten Schmelzwasserabflusses am stârksten war, wie innerhalb oder entlang der Rander des Agassiz-Sees, der Seen der Mattawa-Phase und des Goldtwaith-Meeres, oder in ihren windgeschùtzten Gebieten, besonders wo dièse Wasserflàchen Ubergangszonengrenzen durchschneiden. Die Einwirkungen auf das Klima waren minimal oder inexistent, wo die Wasserflàchengebiete begrenzt waren, wie die kanalisierte Drânage-Route des Ottawa- und Sankt Lorenz-Stroms. Die Ableitung des Abflusses des Agassiz- und Barlow-Ojibway-Sees zur Hudson-Bay hin nach etwa 8.4 ka v.u.Z., stellte die sommerliche Erwàrmung der Ober-flàchenwasser im System der Grofîen Seen und des Sankt Lorenz wieder her und been-dete die von 9.6 bis 8.3 ka dauernde kalte Période

EXIT OF MEAT SLAUGHTER PLANTS DURING IMPLEMENTATION OF THE PR/HACCP REGULATIONS

Implementation of the Pathogen Reduction and Hazard Analysis and Critical Control Points (PR/HACCP) regulations has occurred across all U.S. meat and poultry plants. A probit model is estimated to determine which factors have affected the probability of red meat slaughter plant exit during implementation of the regulations. While controlling for plant-level, company-level, regional-level, and supply conditions that may affect the probability of plant exit, smaller plants are found to exhibit a much greater probability of exit than larger plants. Other factors affecting plant exit include plant age, market share relative to the degree of market concentration, regional entry rates, and state-level wage rates.Agribusiness,

The Impacts of GM Seed Technology on Cotton: Cost of Production in Mississippi, 1996 - 2005

Genetically modified (GM) cotton varieties have changed many aspects of cotton production in the United States. The rapid adoption of GM cotton varieties in Mississippi has allowed producers to alter certain production practices because of added benefits gained from GM varieties. This study analyses some of the effects of certain changes in some of the most relevant components of cotton production on yield that stem from the adoption of GM varieties in Mississippi by comparing production functions from 1996 and 2005.Mississippi cotton production, Genetically Modified cotton varieties, structural change, production function., Crop Production/Industries,

PLANT ENTRY AND EXIT FROM THE MEATPACKING INDUSTRY DURING PATHOGEN REDUCTION AND HACCP IMPLEMENTATION

Implementation of the Pathogen Reduction and Hazard Analysis and Critical Control Points (PR/HACCP) regulations has now occurred across all U.S. meat and poultry plants. Using databases of plants under federal inspection, we estimate a probit model to determine which factors have affected the probability of exit of meat slaughtering plants during implementation of the regulations.Industrial Organization, Livestock Production/Industries,

Key Equations in the Tuljapurkar-Lee Model of the Social Security System

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