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Philip Cook

Duke University, Sanford School of Public Policy, Faculty Member

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I've been on the Duke University faculty since 1973 in Public Policy and Economics. I'm a member of NBER and the National Academy of Medicine. My main current interests are gun violence prevention through regulation and improved police practice. My methodological interests are quasi-experimental methods and cost-benefit analysis.

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alessandro acquisti

Carnegie Mellon University

Armando Marques-Guedes

UNL - New University of Lisbon

Universidade Federal do Rio de Janeiro (UFRJ)

Washington Center for Consciousness Studies

Andres Antillano

Universidad Central de Venezuela

Juan Pablo Roldán

Universidad del Norte Santo Tomás de Aquino

Luciana Boiteux

Universidade Federal do Rio de Janeiro (UFRJ)

Bruce Rogers-Vaughn

Vanderbilt University

Robert J Kaminski

University of South Carolina

Bruno Amaral Machado

Centro Universitario de Brasilia - UniCEUB

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Papers by Philip Cook

Public Safety through Private Action: An economic assessment of BIDs, locks, and citizen cooperation

Seunghoon Han and Maeve Gearing provided excellent research assistance. Partial support for this ... more Seunghoon Han and Maeve Gearing provided excellent research assistance. Partial support for this research was provided through a cooperative agreement from the Centers for Disease Control and Prevention (CDC) (1U49CE000773). Thanks to Jens Ludwig,Tracey Meares, and conference attendees for their suggestions on an earlier draft. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research. NBER working papers are circulated for discussion and comment purposes. They have not been peerreviewed or been subject to the review by the NBER Board of Directors that accompanies official NBER publications.

The Social Costs of Gun Ownership

This paper provides new estimates of the effect of household gun prevalence on homicide rates, an... more This paper provides new estimates of the effect of household gun prevalence on homicide rates, and infers the marginal external cost of handgun ownership. The estimates utilize a superior proxy for gun prevalence, the percentage of suicides committed with a gun, which we validate. Using countyand state-level panels for 20 years, we estimate the elasticity of homicide with respect to gun prevalence as between +.1 and +.3. All of the effect of gun prevalence is on gun homicide rates. Under certain reasonable assumptions, the average annual marginal social cost of household gun

Correcting Misinformation on Firearms Injuries

JAMA network open, Dec 13, 2022

Accurate data on the nature of firearm injuries are essential for crafting effective policies for... more Accurate data on the nature of firearm injuries are essential for crafting effective policies for prevention but are currently lacking. It has been established that medical record coders often misclassify assault cases as "unintentional," with the result that publicly available statistics on nonfatal firearms injuries are heavily biased with respect to the distribution of intents. The study by

Why Does Right-to-Carry Cause Violent Crime to Increase?

Reducing Misuse of Handguns by Rural Youth-Focus on the Parents

JAMA network open, 2022

Children drinking private well water have higher blood lead than those with city water

Proceedings of the National Academy of Sciences, 2020

Significance In the United States, 13% of households depend on an unregulated private well for th... more Significance In the United States, 13% of households depend on an unregulated private well for their water. Compared with children in houses served by a regulated water utility, children in these homes have a 25% increased risk of elevated blood lead. Because lead is a neurotoxin, these children are at greater risk of experiencing irreversible cognitive damage, which can decrease their performance in school and increase their risks of behavioral problems. This study assesses associations between children’s blood lead and dependence on an unregulated private well for drinking water. It highlights the need for interventions to control lead corrosion from plumbing and well components (such as drop pipes, pump parts, and valves and fittings) in households depending on private wells.

Response to Comments

Addiction, 2007

This section offers responses to general comments on aspects of the study from one or more review... more This section offers responses to general comments on aspects of the study from one or more reviewers. General Response 1: Recharge and precipitation estimates One reviewer questioned the accuracy of the precipitation data. In the draft report we used data from the Lynden www.wundergound.com site for precipitation data on dates when the weather station at the study site was not working. At the suggestion of the commenter, we used precipitation data estimated from the Abbotsford, B.C. Airport climate station (Environment Canada) 7 miles east and slightly north of the study site. Precipitation data for 1,072 dates when precipitation data are available at both the on-site weather station and Abbotsford Airport were significantly correlated (r 2 = 0.764). The precipitation at the study site according to regression of the two data sets was 70.7% of that at Abbotsford Airport. Therefore, for dates when the on-site weather station was down, precipitation at the study site was estimated as 70.7% of the Abbotsford Airport value for that date. In the final report we used the combined precipitation data (1,262 values from the on-site weather station and 418 values estimated from Abbotsford Airport) to estimate monthly recharge using a water balance method similar to methods used in Kuipers et al. (2012) and Malekani (2012) near Abbotsford, B.C. Another commenter suggested we use the Water Table Fluctuation Method (WTF) for estimating recharge (Healy and Scanlon, 2010), but we found that this method overestimates recharge where the vadose zone is less than 3.5 m (11.5 feet) thick. Because the vadose zone at the study site varied from 0 to 11 feet thick during the study, the WTF Method was not applicable. General Response 2: Estimating nitrogen loading Several comments suggested using "plant-available nitrogen" for loading estimates rather than total N, because not all of the applied total N is immediately available to the crop. In the draft report we used only the total N method. In the final report we present and compare the 3 methods listed below. Mass balance results using the 3 methods varied widely. We selected the Sullivan (2008) method to estimate plantavailable N because it is the most up-to-date and best-documented method for western Washington. 1. Sullivan (2008). 2. Sullivan (2008) does not account for the effect of higher than average soil organic matter concentration at the study site, which can affect soil mineralization. For this reason we used the part of the Sullivan method that estimates the nitrogen contribution for the current year and substituted 150 lb/acre for the amount mineralized from previous years (20 lb/acre for each 1% of organic carbon (OC) based on the average OC of 7.5% measured in the field during the study). 3. The method used in the draft (total nitrogen) except that the contribution from soil organic matter was deleted. This method uses total nitrogen, not all of which is available the year it is applied. However, this method assumes that the amount of nitrogen that is not available in the current year's applications is balanced out by the amount that becomes available from the soil from past years. General Response 3. Soil nitrate was not designed to be an indicator of groundwater effects. A few commenters noted that the post-harvest soil nitrate test (PSNT; Sullivan and Cogger, 2003) was not designed to be an indicator of groundwater nitrate leaching effects. We recognize that the test was not designed as an indicator of groundwater effects. However, the PSNT is one of the tools used to decide how Response to Comments-Page 4 to adjust future nutrient loading to a field. In this way it influences the potential leaching by guiding the amount and timing of future nutrient applications. General Response 4: Show mean shallow groundwater nitrate concentrations (not just results for well AKG725) for comparisons with nitrogen mass balance (N Excess) estimates and soil nitrate. Two reviewers suggested including nitrate concentrations not only for the most affected monitoring well but also the mean of all 6 shallow monitoring wells in comparisons with nitrogen mass balance and soil nitrate results. We shifted the emphasis of groundwater analyses to the mean concentrations in the final report General Response 5: Influence of upgradient groundwater on monitoring well samples Dr. Thomas Harter (UC, Davis) suggested adding an explanation in the Discussion section of the influence of upgradient activities based on the velocity estimates in the draft report and the impact of recharge on vertical velocity. We used this method to calculate the average age of the groundwater sampled and the average distance upgradient that the samples represented as described in the final report. Response to Comments-Page 5 General Comments This section offers general comments on aspects of the study from individual reviewers. General Comment 1: Avoid spring manure applications Dr. Thomas Harter (UC, Davis) offered these suggestions based on the groundwater response to spring manure applications described on p. 59: "From an agronomic perspective, this seems to indicate a strong recommendation for avoiding spring applications altogether, given that * there is substantial soil organic matter anyway * higher temps will mineralize SOM and make some nitrogen plant available * N uptake by the grass is still limited" Wet conditions that postponed the first grass harvest until April 2, 2006 and the first manure application until April 27, (6 to 10 weeks later than in previous years) prompted this comment: "This indicates the need to recommend that annual application of manure must be allowed to vary according to the crop uptake and to consider the coldest/wettest conceivable year as the limiting case for sizing dairies/creating DNMPs. Dairies should be planning to either keep the herd size small enough to allow for complete manure disposal even in a relatively cold/wet year with a relatively short growing season, or have sufficiently large application area for that type of year, or have alternative export mechanisms for those years." In another section, TH recommends that based on the climate and shallow water table, manure only be applied from May through August. Response to General Comment 1: Comments were noted. General Comment 2: Winter soil nitrate as an indicator of leachate concentration Dr. Bernie Zebarth (Agriculture Canada) wrote (p. 19 comment) "there is considerable new evidence that winter nitrogen processes are more important than previously thought." In email correspondence, Zebarth (2013) describes agricultural research studies at 10 sites across Canada (including the Abbotsford, B.C. area) that indicates that winter mineralization can increase in the winter. They have found that the soil nitrifier and denitrifier communities are functioning throughout winter. They also found that bacterial community composition changes during the winter, suggesting adaptation strategies to cope with cold conditions. Zebarth questioned using winter soil nitrate values to estimate leaching to groundwater, because the soil nitrate concentrations used do not include the nitrate mineralized during the late winter/spring that has already leached and so would underestimate the amount leached. "In the winter period, any nitrate formed is leached as quickly as it is produced. Thus, winter soil sampling is of limited benefit as an indicator of leaching during the winter period. We have done winter sampling and so have the evidence of this. "(Comment on p. 67, last paragraph) A related comment from Dr. Zebarth on p. 67, 3 rd paragraph: "In the Pacific Northwest, it is unlikely the post-harvest test will overestimate nitrate leaching. It is much more likely to underestimate because when Response to Comments-Page 6 you measure at any one time, you do not measure all the nitrate that will leach. It (post harvest soil nitrate testing) is primarily a useful tool for identifying fields with excessive N inputs." Response to General Comment 2: We recognize that the winter soil nitrate values used in this section of the report are probably an underestimate of the leaching potential. We removed this analysis, because the BACKCAST model provides a more accurate representation of nitrate movement in the January-March period. General Comment 3: Incorrect locations for monitoring wells Chris Clark, Whatcom Conservation District, noticed that the monitoring well locations in the draft report were not accurate and that this may have affected estimates for the hydraulic gradient and groundwater velocity. Response to General Comment 3: On June 18, 2013, Ecology used a more sensitive GPS instrument (Trimble GeoExplorer 2005) than originally used to record the monitoring well locations. The more accurate measurements were used in the final report to re-draw water table contours, recalculate the horizontal groundwater gradients and recalculate groundwater velocity. The revised well locations do not affect the hydraulic conductivity calculations, because hydraulic conductivity is only a function of the soil properties at the specific location. We used March 2, 2005 for the typical spring water level contours instead of March 28, 2007 in the draft report, because the 2007 elevations were the highest observed during the four years. The water table elevations in March 2005 were more representative of spring conditions observed. Response to Comments-Page 7 Comments from Chris Clark, Whatcom Conservation District p. x, 6 th paragraph. Comment: The number of dairies has declined. The average size has decreased. The intensity has decreased due to: • Requirements of farm plans • Requirements of nutrient balance • Reduced competition • Switch to berry production allows use of ground in longer rotation Response: We removed the reference to changes in dairy intensity and nutrient loading over the SBA per Whatcom CD's comment. A more detailed analysis would be needed...

Sibling Spillovers: Having an Academically Successful Older Sibling May Be More Important for Children in Disadvantaged Families

American Journal of Sociology, Mar 1, 2023

Oxford University Press eBooks, 2014

Introduction 1. America and Its Guns 2. Reasons for Owning a Firearm 3. The Value of Guns for Saf... more Introduction 1. America and Its Guns 2. Reasons for Owning a Firearm 3. The Value of Guns for Safety and Protection 4. The Costs of Gun Violence 5. Causes of Gun Violence 6. Manufacture and Marketing of Guns 7. How America Regulates Firearms 8. Effectiveness of Firearms Policy 9. Guns and Gun Control in History 10. Public Opinion and Political Party Positions on Guns 11. The Gun Rights Movement 12. The Gun Control Movement 13. Gun Policy Going Forward Bibliography Index

Should Sixth Grade Be in Elementary or Middle School? An Analysis of Grade Configuration and Student Behavior

Kidney Donation and the Consent of the Poor

Social Science Research Network, 2020

Manufacture and Marketing of Guns

How Large Is the Gun Industry in America? The gun industry itself is rather small by traditional ... more

The Harm Done by Guns

How Many Americans Are Killed or Injured by Gunfire? Approximately 1 million Americans have died ... more

The Gun Violence Prevention Movement

What Is the Gun Violence Prevention Movement? Like the gun rights movement, the gun violence prev... more What Is the Gun Violence Prevention Movement? Like the gun rights movement, the gun violence prevention movement includes national, state, and local organizations. Some are single-issue organizations, spending all their time on gun violence prevention, while others are multi-issue allies from the women’s, religious,...

State and Local Prevalence of Firearms Ownership: Measurement, Structure, and Trends

Of the readily computed proxies for the prevalence of gun ownership, one, the percentage of suici... more Of the readily computed proxies for the prevalence of gun ownership, one, the percentage of suicides committed with a gun, performs consistently better than the others in cross-section comparisons. It is readily computed for states and counties and has a high degree of validity when tested against surveybased estimates. It also appears valid as a proxy for changes over time in gun prevalence, at least at the regional level. Our analysis of this proxy measure for the period 1979-1997 demonstrates that the geographic structure of gun ownership has been highly stable. That structure is closely linked to rural tradition. There is, however, some tendency toward homogenization over this period, with highprevalence states trending down and low-prevalence states trending up.

Effectiveness of Firearms Policy

With So Many Guns Out There, Is There Any Point to Gun Control? Yes. The evidence suggests that c... more

Sibling Spillovers: Having an Academically Successful Older Sibling May be More Important for Children in Disadvantaged Families

Social Science Research Network, 2020

This paper examines causal sibling spillover effects among socially advantaged (e.g. white, two-p... more This paper examines causal sibling spillover effects among socially advantaged (e.g. white, two-parent, or non-poor school district) and disadvantaged families (e.g. black, single-mother, or poor school district) in elementary and middle school. Exploiting discontinuities in school starting age created by North Carolina school entry laws, we adopt a quasi-experimental approach and compare test scores of public school students whose older siblings were born shortly before and after the school entry cutoff date. We find that individuals whose older siblings were born shortly after the school entry cutoff date have significantly higher scores in middle school, and that this positive spillover effect is particularly large among disadvantaged families. We estimate that these spillover effects account for more than one third of observed statistical associations in test scores between siblings, and the magnitude is much larger for disadvantaged families than advantaged families. Our results suggest that educational spillover effects from older to younger siblings lead to greater divergence in academic outcomes between families.

If We Pay Football Players, Why Not Kidney Donors?

Organs and Inducements

Law and contemporary problems, Jun 22, 2014

The Organs and Inducements symposium originated from two developments: (1) the large and growing ... more The Organs and Inducements symposium originated from two developments: (1) the large and growing gap between kidney supply and need for people with end-stage renal disease and (2) the failure of recent policy and medical innovations to reverse that trend. The gap between kidney need and supply became visible after the United Network for Organ Sharing data system first went online in 1995 and has been growing ever since. (1) Over the next decade through 2006, transplants increased but the number of patients in need of kidneys grew faster than the supply of kidneys available for transplantation. Since 2006 the need for kidneys has continued to increase, albeit slowly, but the number of suitable kidneys available for transplantation has plateaued, resulting in a still-further widening of the gap. (2) Today, over 7500 patients with end-stage renal disease die each year while awaiting a transplant or become too sick to transplant, while many more languish on the kidney waiting list, which passed 100,000 persons for the first time this year. (3) Although recent advances in kidney transplantation, such as kidney paired donation and nonsimultaneous, extended, altruistic donor (NEAD) chains hold great promise, the number of transplants performed using such techniques remains small and has failed to stem the trend of unmet need. (4) Most of those on the waiting list are on dialysis, a costly and time-consuming procedure that is far less satisfactory than transplantation in sustaining either the quality or duration of life for renal patients. (5) From one perspective, this great loss of life is tragic in that it is foreseeable but unnecessary. Recent evidence suggests that if kidney donors were offered a reasonable payment, enough of them could be recruited to close the current gap, thereby saving thousands of lives and reducing the overall public expenditures on renal disease. (6) From another perspective, paying someone to donate a body part is immoral per se, even if the medical consequences to the donor are minimal and the choice to donate is deliberate and carefully administered. This latter view is incorporated in current law in the United States and all but a handful of other nations in the world. (7) We convened an interdisciplinary discussion at Duke University in the spring of 2013 to discuss these issues, with a particular focus on potential next steps in the long-running debate about methods to increase the supply of transplantable organs. We purposely employed the term "inducements" rather than "incentives," believing that the term "incentives" had become too closely tied with organ markets in the traditional sense--compensation for organs with money, vouchers, or some close cousin. In contrast, we viewed the phrase "inducement" as potentially signifying something broader and more inclusive. According to Merriam-Webster, an inducement is simply "a motive or consideration that leads one to action." (8) We thus invited discussion and investigation, not only of proposals to increase organ supply that involved offering donors monetary or similar compensation, but also more subtle means to facilitate and encourage organ donation. From our perspective, then, inducements could range from public-awareness campaigns exhorting people to donate and informing them of the severity of the organ shortage at one end of the spectrum to outright organ-auction markets at the other end of the spectrum. But we largely expected authors to address the many interesting variations on potential inducement schemes in between those two extremes, and that is what our participants did. The Kidney Transplantation Primer by Philip J. Cook and Kimberly D. Krawiec sets the stage for the discussion by quantitatively documenting the growing gap between kidney need and supply. Cook and Krawiec demonstrate that the current system provides only about half as many kidneys as are needed for transplantation. …

Distinguishing Spurious and Real Peer Effects: Evidence from Artificial Societies, Small-Group Experiments, and Real Schoolyards

Public Safety through Private Action: An economic assessment of BIDs, locks, and citizen cooperation

Seunghoon Han and Maeve Gearing provided excellent research assistance. Partial support for this ... more Seunghoon Han and Maeve Gearing provided excellent research assistance. Partial support for this research was provided through a cooperative agreement from the Centers for Disease Control and Prevention (CDC) (1U49CE000773). Thanks to Jens Ludwig,Tracey Meares, and conference attendees for their suggestions on an earlier draft. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research. NBER working papers are circulated for discussion and comment purposes. They have not been peerreviewed or been subject to the review by the NBER Board of Directors that accompanies official NBER publications.

The Social Costs of Gun Ownership

This paper provides new estimates of the effect of household gun prevalence on homicide rates, an... more This paper provides new estimates of the effect of household gun prevalence on homicide rates, and infers the marginal external cost of handgun ownership. The estimates utilize a superior proxy for gun prevalence, the percentage of suicides committed with a gun, which we validate. Using countyand state-level panels for 20 years, we estimate the elasticity of homicide with respect to gun prevalence as between +.1 and +.3. All of the effect of gun prevalence is on gun homicide rates. Under certain reasonable assumptions, the average annual marginal social cost of household gun

Correcting Misinformation on Firearms Injuries

JAMA network open, Dec 13, 2022

Accurate data on the nature of firearm injuries are essential for crafting effective policies for... more Accurate data on the nature of firearm injuries are essential for crafting effective policies for prevention but are currently lacking. It has been established that medical record coders often misclassify assault cases as "unintentional," with the result that publicly available statistics on nonfatal firearms injuries are heavily biased with respect to the distribution of intents. The study by

Why Does Right-to-Carry Cause Violent Crime to Increase?

Reducing Misuse of Handguns by Rural Youth-Focus on the Parents

JAMA network open, 2022

Children drinking private well water have higher blood lead than those with city water

Proceedings of the National Academy of Sciences, 2020

Significance In the United States, 13% of households depend on an unregulated private well for th... more Significance In the United States, 13% of households depend on an unregulated private well for their water. Compared with children in houses served by a regulated water utility, children in these homes have a 25% increased risk of elevated blood lead. Because lead is a neurotoxin, these children are at greater risk of experiencing irreversible cognitive damage, which can decrease their performance in school and increase their risks of behavioral problems. This study assesses associations between children’s blood lead and dependence on an unregulated private well for drinking water. It highlights the need for interventions to control lead corrosion from plumbing and well components (such as drop pipes, pump parts, and valves and fittings) in households depending on private wells.

Response to Comments

Addiction, 2007

This section offers responses to general comments on aspects of the study from one or more review... more This section offers responses to general comments on aspects of the study from one or more reviewers. General Response 1: Recharge and precipitation estimates One reviewer questioned the accuracy of the precipitation data. In the draft report we used data from the Lynden www.wundergound.com site for precipitation data on dates when the weather station at the study site was not working. At the suggestion of the commenter, we used precipitation data estimated from the Abbotsford, B.C. Airport climate station (Environment Canada) 7 miles east and slightly north of the study site. Precipitation data for 1,072 dates when precipitation data are available at both the on-site weather station and Abbotsford Airport were significantly correlated (r 2 = 0.764). The precipitation at the study site according to regression of the two data sets was 70.7% of that at Abbotsford Airport. Therefore, for dates when the on-site weather station was down, precipitation at the study site was estimated as 70.7% of the Abbotsford Airport value for that date. In the final report we used the combined precipitation data (1,262 values from the on-site weather station and 418 values estimated from Abbotsford Airport) to estimate monthly recharge using a water balance method similar to methods used in Kuipers et al. (2012) and Malekani (2012) near Abbotsford, B.C. Another commenter suggested we use the Water Table Fluctuation Method (WTF) for estimating recharge (Healy and Scanlon, 2010), but we found that this method overestimates recharge where the vadose zone is less than 3.5 m (11.5 feet) thick. Because the vadose zone at the study site varied from 0 to 11 feet thick during the study, the WTF Method was not applicable. General Response 2: Estimating nitrogen loading Several comments suggested using "plant-available nitrogen" for loading estimates rather than total N, because not all of the applied total N is immediately available to the crop. In the draft report we used only the total N method. In the final report we present and compare the 3 methods listed below. Mass balance results using the 3 methods varied widely. We selected the Sullivan (2008) method to estimate plantavailable N because it is the most up-to-date and best-documented method for western Washington. 1. Sullivan (2008). 2. Sullivan (2008) does not account for the effect of higher than average soil organic matter concentration at the study site, which can affect soil mineralization. For this reason we used the part of the Sullivan method that estimates the nitrogen contribution for the current year and substituted 150 lb/acre for the amount mineralized from previous years (20 lb/acre for each 1% of organic carbon (OC) based on the average OC of 7.5% measured in the field during the study). 3. The method used in the draft (total nitrogen) except that the contribution from soil organic matter was deleted. This method uses total nitrogen, not all of which is available the year it is applied. However, this method assumes that the amount of nitrogen that is not available in the current year's applications is balanced out by the amount that becomes available from the soil from past years. General Response 3. Soil nitrate was not designed to be an indicator of groundwater effects. A few commenters noted that the post-harvest soil nitrate test (PSNT; Sullivan and Cogger, 2003) was not designed to be an indicator of groundwater nitrate leaching effects. We recognize that the test was not designed as an indicator of groundwater effects. However, the PSNT is one of the tools used to decide how Response to Comments-Page 4 to adjust future nutrient loading to a field. In this way it influences the potential leaching by guiding the amount and timing of future nutrient applications. General Response 4: Show mean shallow groundwater nitrate concentrations (not just results for well AKG725) for comparisons with nitrogen mass balance (N Excess) estimates and soil nitrate. Two reviewers suggested including nitrate concentrations not only for the most affected monitoring well but also the mean of all 6 shallow monitoring wells in comparisons with nitrogen mass balance and soil nitrate results. We shifted the emphasis of groundwater analyses to the mean concentrations in the final report General Response 5: Influence of upgradient groundwater on monitoring well samples Dr. Thomas Harter (UC, Davis) suggested adding an explanation in the Discussion section of the influence of upgradient activities based on the velocity estimates in the draft report and the impact of recharge on vertical velocity. We used this method to calculate the average age of the groundwater sampled and the average distance upgradient that the samples represented as described in the final report. Response to Comments-Page 5 General Comments This section offers general comments on aspects of the study from individual reviewers. General Comment 1: Avoid spring manure applications Dr. Thomas Harter (UC, Davis) offered these suggestions based on the groundwater response to spring manure applications described on p. 59: "From an agronomic perspective, this seems to indicate a strong recommendation for avoiding spring applications altogether, given that * there is substantial soil organic matter anyway * higher temps will mineralize SOM and make some nitrogen plant available * N uptake by the grass is still limited" Wet conditions that postponed the first grass harvest until April 2, 2006 and the first manure application until April 27, (6 to 10 weeks later than in previous years) prompted this comment: "This indicates the need to recommend that annual application of manure must be allowed to vary according to the crop uptake and to consider the coldest/wettest conceivable year as the limiting case for sizing dairies/creating DNMPs. Dairies should be planning to either keep the herd size small enough to allow for complete manure disposal even in a relatively cold/wet year with a relatively short growing season, or have sufficiently large application area for that type of year, or have alternative export mechanisms for those years." In another section, TH recommends that based on the climate and shallow water table, manure only be applied from May through August. Response to General Comment 1: Comments were noted. General Comment 2: Winter soil nitrate as an indicator of leachate concentration Dr. Bernie Zebarth (Agriculture Canada) wrote (p. 19 comment) "there is considerable new evidence that winter nitrogen processes are more important than previously thought." In email correspondence, Zebarth (2013) describes agricultural research studies at 10 sites across Canada (including the Abbotsford, B.C. area) that indicates that winter mineralization can increase in the winter. They have found that the soil nitrifier and denitrifier communities are functioning throughout winter. They also found that bacterial community composition changes during the winter, suggesting adaptation strategies to cope with cold conditions. Zebarth questioned using winter soil nitrate values to estimate leaching to groundwater, because the soil nitrate concentrations used do not include the nitrate mineralized during the late winter/spring that has already leached and so would underestimate the amount leached. "In the winter period, any nitrate formed is leached as quickly as it is produced. Thus, winter soil sampling is of limited benefit as an indicator of leaching during the winter period. We have done winter sampling and so have the evidence of this. "(Comment on p. 67, last paragraph) A related comment from Dr. Zebarth on p. 67, 3 rd paragraph: "In the Pacific Northwest, it is unlikely the post-harvest test will overestimate nitrate leaching. It is much more likely to underestimate because when Response to Comments-Page 6 you measure at any one time, you do not measure all the nitrate that will leach. It (post harvest soil nitrate testing) is primarily a useful tool for identifying fields with excessive N inputs." Response to General Comment 2: We recognize that the winter soil nitrate values used in this section of the report are probably an underestimate of the leaching potential. We removed this analysis, because the BACKCAST model provides a more accurate representation of nitrate movement in the January-March period. General Comment 3: Incorrect locations for monitoring wells Chris Clark, Whatcom Conservation District, noticed that the monitoring well locations in the draft report were not accurate and that this may have affected estimates for the hydraulic gradient and groundwater velocity. Response to General Comment 3: On June 18, 2013, Ecology used a more sensitive GPS instrument (Trimble GeoExplorer 2005) than originally used to record the monitoring well locations. The more accurate measurements were used in the final report to re-draw water table contours, recalculate the horizontal groundwater gradients and recalculate groundwater velocity. The revised well locations do not affect the hydraulic conductivity calculations, because hydraulic conductivity is only a function of the soil properties at the specific location. We used March 2, 2005 for the typical spring water level contours instead of March 28, 2007 in the draft report, because the 2007 elevations were the highest observed during the four years. The water table elevations in March 2005 were more representative of spring conditions observed. Response to Comments-Page 7 Comments from Chris Clark, Whatcom Conservation District p. x, 6 th paragraph. Comment: The number of dairies has declined. The average size has decreased. The intensity has decreased due to: • Requirements of farm plans • Requirements of nutrient balance • Reduced competition • Switch to berry production allows use of ground in longer rotation Response: We removed the reference to changes in dairy intensity and nutrient loading over the SBA per Whatcom CD's comment. A more detailed analysis would be needed...

Sibling Spillovers: Having an Academically Successful Older Sibling May Be More Important for Children in Disadvantaged Families

American Journal of Sociology, Mar 1, 2023

Oxford University Press eBooks, 2014

Introduction 1. America and Its Guns 2. Reasons for Owning a Firearm 3. The Value of Guns for Saf... more Introduction 1. America and Its Guns 2. Reasons for Owning a Firearm 3. The Value of Guns for Safety and Protection 4. The Costs of Gun Violence 5. Causes of Gun Violence 6. Manufacture and Marketing of Guns 7. How America Regulates Firearms 8. Effectiveness of Firearms Policy 9. Guns and Gun Control in History 10. Public Opinion and Political Party Positions on Guns 11. The Gun Rights Movement 12. The Gun Control Movement 13. Gun Policy Going Forward Bibliography Index

Should Sixth Grade Be in Elementary or Middle School? An Analysis of Grade Configuration and Student Behavior

Kidney Donation and the Consent of the Poor

Social Science Research Network, 2020

Manufacture and Marketing of Guns

How Large Is the Gun Industry in America? The gun industry itself is rather small by traditional ... more

The Harm Done by Guns

How Many Americans Are Killed or Injured by Gunfire? Approximately 1 million Americans have died ... more

The Gun Violence Prevention Movement

What Is the Gun Violence Prevention Movement? Like the gun rights movement, the gun violence prev... more What Is the Gun Violence Prevention Movement? Like the gun rights movement, the gun violence prevention movement includes national, state, and local organizations. Some are single-issue organizations, spending all their time on gun violence prevention, while others are multi-issue allies from the women’s, religious,...

State and Local Prevalence of Firearms Ownership: Measurement, Structure, and Trends

Of the readily computed proxies for the prevalence of gun ownership, one, the percentage of suici... more Of the readily computed proxies for the prevalence of gun ownership, one, the percentage of suicides committed with a gun, performs consistently better than the others in cross-section comparisons. It is readily computed for states and counties and has a high degree of validity when tested against surveybased estimates. It also appears valid as a proxy for changes over time in gun prevalence, at least at the regional level. Our analysis of this proxy measure for the period 1979-1997 demonstrates that the geographic structure of gun ownership has been highly stable. That structure is closely linked to rural tradition. There is, however, some tendency toward homogenization over this period, with highprevalence states trending down and low-prevalence states trending up.

Effectiveness of Firearms Policy

With So Many Guns Out There, Is There Any Point to Gun Control? Yes. The evidence suggests that c... more

Sibling Spillovers: Having an Academically Successful Older Sibling May be More Important for Children in Disadvantaged Families

Social Science Research Network, 2020

This paper examines causal sibling spillover effects among socially advantaged (e.g. white, two-p... more This paper examines causal sibling spillover effects among socially advantaged (e.g. white, two-parent, or non-poor school district) and disadvantaged families (e.g. black, single-mother, or poor school district) in elementary and middle school. Exploiting discontinuities in school starting age created by North Carolina school entry laws, we adopt a quasi-experimental approach and compare test scores of public school students whose older siblings were born shortly before and after the school entry cutoff date. We find that individuals whose older siblings were born shortly after the school entry cutoff date have significantly higher scores in middle school, and that this positive spillover effect is particularly large among disadvantaged families. We estimate that these spillover effects account for more than one third of observed statistical associations in test scores between siblings, and the magnitude is much larger for disadvantaged families than advantaged families. Our results suggest that educational spillover effects from older to younger siblings lead to greater divergence in academic outcomes between families.

If We Pay Football Players, Why Not Kidney Donors?

Organs and Inducements

Law and contemporary problems, Jun 22, 2014

The Organs and Inducements symposium originated from two developments: (1) the large and growing ... more The Organs and Inducements symposium originated from two developments: (1) the large and growing gap between kidney supply and need for people with end-stage renal disease and (2) the failure of recent policy and medical innovations to reverse that trend. The gap between kidney need and supply became visible after the United Network for Organ Sharing data system first went online in 1995 and has been growing ever since. (1) Over the next decade through 2006, transplants increased but the number of patients in need of kidneys grew faster than the supply of kidneys available for transplantation. Since 2006 the need for kidneys has continued to increase, albeit slowly, but the number of suitable kidneys available for transplantation has plateaued, resulting in a still-further widening of the gap. (2) Today, over 7500 patients with end-stage renal disease die each year while awaiting a transplant or become too sick to transplant, while many more languish on the kidney waiting list, which passed 100,000 persons for the first time this year. (3) Although recent advances in kidney transplantation, such as kidney paired donation and nonsimultaneous, extended, altruistic donor (NEAD) chains hold great promise, the number of transplants performed using such techniques remains small and has failed to stem the trend of unmet need. (4) Most of those on the waiting list are on dialysis, a costly and time-consuming procedure that is far less satisfactory than transplantation in sustaining either the quality or duration of life for renal patients. (5) From one perspective, this great loss of life is tragic in that it is foreseeable but unnecessary. Recent evidence suggests that if kidney donors were offered a reasonable payment, enough of them could be recruited to close the current gap, thereby saving thousands of lives and reducing the overall public expenditures on renal disease. (6) From another perspective, paying someone to donate a body part is immoral per se, even if the medical consequences to the donor are minimal and the choice to donate is deliberate and carefully administered. This latter view is incorporated in current law in the United States and all but a handful of other nations in the world. (7) We convened an interdisciplinary discussion at Duke University in the spring of 2013 to discuss these issues, with a particular focus on potential next steps in the long-running debate about methods to increase the supply of transplantable organs. We purposely employed the term "inducements" rather than "incentives," believing that the term "incentives" had become too closely tied with organ markets in the traditional sense--compensation for organs with money, vouchers, or some close cousin. In contrast, we viewed the phrase "inducement" as potentially signifying something broader and more inclusive. According to Merriam-Webster, an inducement is simply "a motive or consideration that leads one to action." (8) We thus invited discussion and investigation, not only of proposals to increase organ supply that involved offering donors monetary or similar compensation, but also more subtle means to facilitate and encourage organ donation. From our perspective, then, inducements could range from public-awareness campaigns exhorting people to donate and informing them of the severity of the organ shortage at one end of the spectrum to outright organ-auction markets at the other end of the spectrum. But we largely expected authors to address the many interesting variations on potential inducement schemes in between those two extremes, and that is what our participants did. The Kidney Transplantation Primer by Philip J. Cook and Kimberly D. Krawiec sets the stage for the discussion by quantitatively documenting the growing gap between kidney need and supply. Cook and Krawiec demonstrate that the current system provides only about half as many kidneys as are needed for transplantation. …

Distinguishing Spurious and Real Peer Effects: Evidence from Artificial Societies, Small-Group Experiments, and Real Schoolyards