Quantifying uncertainty in the biospheric carbon flux for England and Wales

Summary.  A crucial issue in the current global warming debate is the effect of vegetation and soils on carbon dioxide (CO₂) concentrations in the atmosphere. Vegetation can extract CO₂ through photosynthesis, but respiration, decay of soil organic matter and disturbance effects such as fire return it to the atmosphere. The balance of these processes is the net carbon flux. To estimate the biospheric carbon flux for England and Wales, we address the statistical problem of inference for the sum of multiple outputs from a complex deterministic computer code whose input parameters are uncertain. The code is a process model which simulates the carbon dynamics of vegetation and soils, including the amount of carbon that is stored as a result of photosynthesis and the amount that is returned to the atmosphere through respiration. The aggregation of outputs corresponding to multiple sites and types of vegetation in a region gives an estimate of the total carbon flux for that region over a period of time. Expert prior opinions are elicited for marginal uncertainty about the relevant input parameters and for correlations of inputs between sites. A Gaussian process model is used to build emulators of the multiple code outputs and Bayesian uncertainty analysis is then used to propagate uncertainty in the input parameters through to uncertainty on the aggregated output. Numerical results are presented for England and Wales in the year 2000. It is estimated that vegetation and soils in England and Wales constituted a net sink of 7.55 Mt C (1 Mt C = 10¹² g of carbon) in 2000, with standard deviation 0.56 Mt C resulting from the sources of uncertainty that are considered.     

TEACHING TOOLS: ON JOURNALISTS' USE OF MACROECONOMIC CONCEPTS

Five macroeconomic concepts are presented which are prominent in the business sections of newspapers, but which are not given equivalent prominence in macroeconomic textbooks. These are the discouraged worker phenomenon, the use of inventories in forecasting, the effect of changes in the money supply on the bond market, and the effects of inflation and nominal interest rates in the foreign exchange market. These concepts are presented via news clips illustrating the way they typically appear in the press. Instructors are urged to place extra emphasis on these concepts.     

Getting the most for your consulting dollars

Major changes in the health care financing and delivery system have usually been accompanied by an increase in demand within the health care field for consulting services. The passage of Medicare/Medicaid in 1965 is one example. The passage of the DRG-based prospective pricing system in 1983 is another. Both spawned a substantial amount of work, and income, for consulting firms. Now the health care field is engaged in nearly total transformation as the forces of health care reform at the national level are met with myriad adjustments at the local and regional levels. Managed care, already a byword, is being strengthened by a multitude of so-called integrated system initiatives. It is not easy to survive, and the call is out to consultants to save the day, or at least stave off disaster. In the following four articles, Marilyn Kennedy, a member of the ACPE faculty and a consultant herself, gives some advice on how to make the consulting arrangement successful; three physician executives provide a glimpse at consults that have worked, and some that did not work.     

Personal trainer, personal coach

The increasing number of fresh faces in the management ranks, many of them with highly polished credentials but little in the way of practical experience in the work-a-day management world, has increased the need for a new consulting professional--the personal coach. There simply aren't enough volunteer mentors to accommodate the growing medical management profession. Whatever the conditions under which this new professional's services are sought, both the individual to be coached and the organization for which the individual works should approach the arrangement with care and planning. The author offers some guidance for making the arrangement pay off.     

Can you communicate cross-generationally?

What is fractured cross-generational communication? When what one person heard was not what the other person said. Regardless of your age, you need to understand some of the differences in communication styles that must be overcome if people are to work well together. This is especially important in health care right now when there are other pressing issues. Interpreters are at a premium because so much misunderstanding clouds the communication process. Two management strategies are presented that will help bridge the gaps between communication styles.     

How could I have gotten it wrong?

Can you avoid ending up in a career-denting job: Are there potential pitfalls to recognize on the search for a rewarding position? Finding oneself in an impossible job, working for a boss who brings out your worst qualities and deepest insecurities, or joining an organization that is doomed are nightmare scenarios. How do these judgment errors happen? We asked physicians who've been there and, unfortunately, done just that. What they learned might help the rest of us skip the experience.     

On characterizing the normal and poisson distributions

Multivariate normal, correlated multivariate Poisson and multiple Poisson distributions are characterized, in the class of exponential-type distributions, by the properties of the linear combinations of the variables, the properties of their cumulants and the recurance relation between the cumulants.     

Dopamine Genes and Pathological Gambling in Discordant Sib-Pairs

Pathological gambling (PG) is an impulse control disorder that has been considered as a behavioral addiction. Recent studies have suggested the involvement of the dopaminergic system in addictions and impulse control disorders and associations of dopamine receptor genes (DRD1, DRD2, and DRD4) and PG have been reported. In the present study, 140 sib-pairs discordant for the diagnosis of PG (70 males and 70 females on each group) were recruited through the Gambling Outpatient Unit at the Institute of Psychiatry, University of Sao Paulo and were assessed by trained psychiatrists. A family-based association design was chosen to prevent population stratification. All subjects were genotyped for dopamine receptor genes (DRD1 -800 T/C, DRD2 TaqIA RFLP, DRD3 Ser9Gly, DRD4 48bp exon III VNTR, DRD5 (CA) repeat) and the dopamine transporter gene (SCL6A3 40 bp VNTR). Our results suggest the association of PG with DRD1 -800 T/C allele T (P = .03).     

The impact of migration on the well-being of transnational families: new data from sending communities in Mexico

We present results from a new study of the effects of migration to the USA on the well-being of transnational families in high emigration communities within Mexico. Our survey measured the well-being of family members in a variety of domains: economic, health, education, and child development for a representative sample drawn from high migration municipalities. Compared to those with no recent emigrants to the USA, Mexican households sending non-caregivers to the USA appear to gain economically without contributing to problems faced by children. However, when family caregivers migrate to the USA, the remaining members in Mexico struggle to meet the family's needs and children are more vulnerable to educational, emotional, and health problems. Children in households where a caregiver migrated were more likely to have frequent illnesses (10% vs. 3%, p<0.0001), chronic illness (7% vs. 3%, p=0.011), emotional problems (10% vs. 4%, p=0.006), and behavioral problems (17% vs. 10%, p=0.018) compared with children in households where the migrant was not a caregiver. Research, policy, and program implications of these findings are discussed.