What's so Great about the Great Moderation? A Multi-Country Investigation of Time-Varying Volatilities of Output Growth and Inflation

Changes in volatility of output growth and inflation are examined for eight countries with at least 140 years of uninterrupted data. Time-varying parameter vector autoregressions are used to estimate standard deviations of each variable. Both volatilities rise quickly with World War I and its aftermath, stay relatively high until the end of World War II, and then drop rapidly until the mid- to late 1960s. This Postwar Moderation typically yields the largest decline in output growth volatilities. For all countries, volatilities of both output growth and inflation fall more during this Postwar Moderation than during the Great Moderation, and often the difference is huge. Both volatilities typically reach their lowest levels following the Great Moderation. The Great Moderation often counteracts an increase in volatility that took place in the 1970s, particularly for inflation. In nearly all the countries in our sample, the recent financial crisis has eliminated the stability gains associated with the Great Moderation, and sometimes it has even eroded gains made during the Postwar Moderation. Periods in which a fixed exchange rate system was widespread are associated with relatively low volatilities for both variables. Based on our structural VAR identification, permanent shocks to output account for nearly all of the fluctuations in the volatility of output growth while shocks that have only a temporary effect on output explain most of the fluctuations in inflation volatility. These last two findings suggest that changes in the volatility for each variable are primarily driven by a fundamentally different type of disturbance.The Great Moderation, The Postwar Moderation, stochastic volatility, permanent-transitory shock decompositions, Markov Chain Monte Carlo, structural vector autoregressions.

The Time Varying Effects of Permanent and Transitory Shocks to Real Output

Annual changes in volatility of U.S. real output growth and inflation are documented in data from 1870 to 2009 using a time varying parameter VAR model. Both volatilities rise quickly with World War I and its aftermath, stay relatively high until the end of World War II and drop rapidly until the mid to late-1960s. This Postwar Moderation represents the largest decline in volatilities in our sample, much greater than the Great Moderation that began in the 1980s. Fluctuations in output growth volatility are primarily associated with permanent shocks to output while fluctuations in inflation volatility are primarily accounted for by temporary shocks to output. Conditioning on temporary shocks, inflation and output growth are positively correlated. This finding and the ensuing impulse responses are consistent with an aggregate demand interpretation for the temporary shocks. Our model suggests aggregate demand played a key role in the changes in inflation volatility. Conversely, the two variables are negatively correlated when conditioning on permanent shocks, suggesting that these disturbances are associated primarily with aggregate supply. Our results suggest that aggregate supply played an important role in output volatility fluctuations. Most of the impulse responses support an aggregate supply interpretation of permanent shocks. However, for the pre-World War I period, we find that at longer horizons a permanent increase in output is generally associated with an increase in the price level that is frequently statistically significant. This evidence suggests aggregate demand may have had a long-run positive effect on output during the pre-World War I period.The Great Moderation, stochastic volatility, permanent-transitory decompositions, Markov Chain Monte Carlo, structural vector autoregressions.

Greater Moderations

We decompose a 219 year sample of U.S. real output data into permanent and transitory shocks. We find reductions in volatility of output growth and inflation, starting in the mid 1980s, consistent with the “Great Moderation” noted by many others. More importantly, we find periods of even more substantial reduction in volatilities. Output growth and inflation volatilities fell by 60% and 76%, respectively, from shortly after World War II until the mid 1960s. We label this period the Postwar Moderation. Also, the largest reduction in inflation volatility occurred during the Classical Gold Standard period. Results from our empirical model suggest that aggregate supply shocks account for most of the changes in output growth volatility while aggregate demand shocks account for most of the changes in inflation volatility. The timing of the Postwar Moderation, which began almost immediately after passage of the Employment Act of 1946, suggests that policy played a crucial role in this period’s impressive decline in volatilities.The Great Moderation, stochastic volatility, structural VAR

NEEMIS : text of governors presentation of October 6, 1975

Prepared in association with the Alfred P. Sloan School of ManagementThis is the text of a presentation given to the six New England governors on November 7, 1975. The presentation focused on explaining how the New England Energy Management Information System (NEEMIS) has helped the region, what it is, how it will continue to help the region, what unique technology made it possible, what shall be done in the future, and a demonstration of one application

Novel applications of multipurpose robotic arms spanning design fabrication, utility, and art

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 204-208).This work investigates, defines, and expands on the use of robotic arms in digital fabrication, design, and art through methods including 3D printing, milling, sculpting, functionally graded fabrication, construction-scale additive manufacturing, jammable granular system design, light painting, and volumetric sensing. While most current applications of robotics in manufacturing rely on repetitive automation and assembly tasks, the flexibility, dexterity, and precision of industrial robotic arms provide for design opportunities of multi-functionary roles. Through exploration and demonstration, a multipurpose fabrication platform was developed using a KUKA KR5 sixx R850 robotic arm. The platform is capable of conventional manufacturing techniques spanning the three traditional fabrication categories: additive, subtractive, and formative. Case studies and digital design fabrication protocols were developed as part of the robotic platform to demonstrate these three types of fabrication including 3D printing, multi-axis milling, and clay sculpting, respectively. Compound processes, such as combining 3D printing and milling, were developed that offer product-, and process-based improvements over standalone techniques. The benefits and drawbacks of a multi-fabrication platform are discussed, including cost, physical footprint, resolution, and flexibility. In addition to replicating conventional manufacturing techniques with a single robotic platform, several novel applications were developed which take advantage of the flexibility of an arm system. First, functionally graded 3D printing was explored using concrete through which density gradients were shown to achieve higher structural efficiency. A novel construction-scale additive manufacturing process capable of 3D printing building components was developed. Secondly, direct recycling 3D printing was developed where waste thermoplastic products are transformed into feedstock and printed into new components within a single operation. Work conducted on jammed granular structures, where external pressure controls system stiffness and strength, resulted in several new formative fabrication possibilities. Combined with robotics, waste-free digital casting using jammable materials was enabled along with a variety of design projects including the design of robotic arms themselves. Finally, the use of robotic arms for fabrication of material and environmental properties without mechanical force transfer was explored. Coined immaterial fabrication,t his fabrication category captures methods that do not fall within the definitions of additive, subtractive, or formative processes. Work produced in this area includes a volumetric sensing technique and robotic light paintings that reveal thermal, electromagnetic, and optical fields.by Steven J. Keating.S.M

Factors contributing to disparities in mortality among patients with non–small‐cell lung cancer

Historically, non–small‐cell lung cancer (NSCLC) patients who are non‐white, have low incomes, low educational attainment, and non‐private insurance have worse survival. We assessed whether differences in survival were attributable to sociodemographic factors, clinical characteristics at diagnosis, or treatments received. We surveyed a multiregional cohort of patients diagnosed with NSCLC from 2003 to 2005 and followed through 2012. We used Cox proportional hazard analyses to estimate the risk of death associated with race/ethnicity, annual income, educational attainment, and insurance status, unadjusted and sequentially adjusting for sociodemographic factors, clinical characteristics, and receipt of surgery, chemotherapy, and radiotherapy. Of 3250 patients, 64% were white, 16% black, 7% Hispanic, and 7% Asian; 36% of patients had incomes <$20 000/y; 23$60 000/y, not attending college, and not having private insurance were all associated with an increased risk of mortality. Black‐white differences were not statistically significant after adjustment for sociodemographic factors, although patients with patients without a high school diploma and patients with incomes <$40 000/y continued to have an increased risk of mortality. Differences by educational attainment were not statistically significant after adjustment for clinical characteristics. Differences by income were not statistically significant after adjustment for clinical characteristics and treatments. Clinical characteristics and treatments received primarily contributed to mortality disparities by race/ethnicity and socioeconomic status in patients with NSCLC. Additional efforts are needed to assure timely diagnosis and use of effective treatment to lessen these disparities.Using data from the Cancer Care Outcomes Research and Surveillance (CanCORS) consortium, a large, multi‐regional observational study of newly diagnosed cancer patients, we documented higher unadjusted mortality for NSCLC among patients who were black, have lower income, less well‐educated, and with non‐private insurance. We used a series of Cox proportional hazards model to estimate the increased risk of death associated with sociodemographic factors, clinical characteristics, and treatments received to determine what accounted for the disparities. We found that patients’ clinical characteristics and treatments received primarily contributed to the mortality disparities that we observed in patients with NSCLC.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146607/1/cam41796.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146607/2/cam41796_am.pd

Factors contributing to disparities in mortality among patients with non-small-cell lung cancer

Historically, non-small-cell lung cancer (NSCLC) patients who are non-white, have low incomes, low educational attainment, and non-private insurance have worse survival. We assessed whether differences in survival were attributable to sociodemographic factors, clinical characteristics at diagnosis, or treatments received. We surveyed a multiregional cohort of patients diagnosed with NSCLC from 2003 to 2005 and followed through 2012. We used Cox proportional hazard analyses to estimate the risk of death associated with race/ethnicity, annual income, educational attainment, and insurance status, unadjusted and sequentially adjusting for sociodemographic factors, clinical characteristics, and receipt of surgery, chemotherapy, and radiotherapy. Of 3250 patients, 64% were white, 16% black, 7% Hispanic, and 7% Asian; 36% of patients had income