William J. Hill

The Impact of Six Sigma Improvement—A Glimpse into the Future of Statistics

Abstract Six Sigma improvements—a highly disciplined and statistically based approach for removing defects from products, processes, and transactions, involving everybody in the corporation—has been adopted as a major initiative by some of our leading companies. This is fundamentally changing the paradigm of how statistics is applied in business and industry, and has had a career-changing impact on those statisticians who have been involved. We describe the Six Sigma initiative and its evolution, the enthusiastic and visionary support by the CEOs at some major corporations that have embraced it, its successes to date, and the impact on statistics and statisticians. We then turn to a major theme—what statisticians must do to be maximally effective in this exciting new environment. These changes will not be limited to the companies that have adopted Six Sigma, or, for that matter, industry, but are all-pervasive. We discuss the dramatic longer term implications on our profession.

A Steely of the Relationship between Blood Lead Levels and Occupational Air Lead Levels

Abstract This study reports on the relationships between air lead levels and blood lead levels for workers at a group of battery plants. A cross-sectional analysis derived the dose-response relationships for 233 workers at six plants in 1978. A longitudinal analysis followed the blood lead versus air lead relationship over the period January 1976-August 1981 at four of these plants. The two analyses gave similar results. Blood lead levels were found to depend on air lead levels, but plant differences, respirator usage, and individual variation had strong effects on blood lead levels.

Establishing an Office of Scientific and Public Affairs

At its December 1987 meeting, the Board of Directors of the American Statistical Association (ASA) unanimously voted to establish a new Office of Scientific and Public Affairs within ASA. This development marked the culmination of several years of interest by the association in addressing needs to educate policymakers and the general public about the importance of statistics, the use of statistical capability, and the interpretation of statistics. In March 1987 as ASA president I appointed a Committee on Developing an ASA Office of Scientific and Public Affairs, which was charged with presenting a plan for such an office to the board in December 1987. Principal portions of the committees report to the board are published in this article. With the boards approval of funding and position descriptions for the Office of Scientific and Public Affairs (OSPA), the search for the offices first director is proceeding. Implementation of the full core plan proposed by the committee will begin when the director is on board at ASA. From conversations with colleagues in kindred societies, we are conifident that several other associations are pleased with ASAs decision to take a leadership role in this area, and we fully expect that several of these organizations will participate in and lend their support to the many activities that will benefit the statistics profession. I am especially delighted by this new initiative in our association, and look forward to hearing from ASA members about ways in which the OSPA can best serve their needs. We are indebted to the committee for its work, which has assisted ASA in formulating a plan for action in this important area.

Quality improvement approaches for chemical processes

Quality improvement of chemical processes through the use of design of experiments (DOE), variance component analysis, and process noise simulation models is the focus of this report. A case history of a Nylon process serves as the backdrop as to how ef..