James J. Divoky and Mary Anne Rothermel
The purpose of this paper is to explore and analyze the effectiveness of long period supplementary zone rules that can simultaneously increase chart sensitivity to small process…
Abstract
Purpose
The purpose of this paper is to explore and analyze the effectiveness of long period supplementary zone rules that can simultaneously increase chart sensitivity to small process drift and not significantly increase the false alarm rate.
Design/methodology/approach
A stable, on‐target process was simulated and drift induced into the process. The rates of drift varied from 0.03σ to .0003σ per subgroup measurement. A total of 613 different supplementary zone rules were implemented in conjunction with the three‐sigma limiting rule. For each combination, 100,000 observations were simulated and the effect on the false alarm rate and increase in chart sensitivity estimated. An effectiveness measure was developed to relate false alarm rate to chart sensitivity.
Findings
A total of 87 rules were uncovered which effectively detected a wide range of process drifts. When the increase in chart sensitivity is discounted by the false alarm rate, 13 rules increased chart sensitivity by over 10 percent. These rules were based on longer rather than shorter rule length.
Research limitations/implications
The effective rules discovered form a nonlinear pattern in the space the examined rules define. This indicates a direction for future research outside the scope of this study. These rules are also easy to implement in existing Shewhart chart applications where the process drifts at an unknown rate.
Originality/value
While supplementary trend rules have been studied in the past, the extension to zone rules has not been made. This study begins to fill that void and indicates the direction for future efforts in the area.
Details
Keywords
James J. Divoky and Richard W. Taylor
Examines trend rules in conjunction with other well‐knownsupplementary runs rules to assess their impact when used in controlcharting. Focuses on a set of 613 trend rules deemed…
Abstract
Examines trend rules in conjunction with other well‐known supplementary runs rules to assess their impact when used in control charting. Focuses on a set of 613 trend rules deemed as potential candidates to increase the sensitivity of the control chart. The examined rules are viewed in the light of a stable environment, which determines the false alarm rate, and then in an environment in which the process mean is subjected to drift. Results indicate that there are subsets of trend rules that aid in the detection of out‐of‐control conditions depending on the severity of the drift and the number of zonal‐based supplementary runs rules used.
Details
Keywords
The term “medical” will be interpreted broadly to include both basic and clinical sciences, related health fields, and some “medical” elements of biology and chemistry. A…
Abstract
The term “medical” will be interpreted broadly to include both basic and clinical sciences, related health fields, and some “medical” elements of biology and chemistry. A reference book is here defined as any book that is likely to be consulted for factual information more frequently than it will be picked up and read through in sequential order. Medical reference books have a place in public, school, college, and other non‐medical libraries as well as in the wide variety of medical libraries. All of these libraries will be considered in this column. A basic starting collection of medical material for a public library is outlined and described in an article by William and Virginia Beatty that appeared in the May, 1974, issue of American Libraries.
Anne E. Zald and Cathy Seitz Whitaker
Despite the title of this bibliography, there was not a truly underground press in the United States during the 1960s and 1970s. The phrase is amisnomer, reputedly coined on the…
Abstract
Despite the title of this bibliography, there was not a truly underground press in the United States during the 1960s and 1970s. The phrase is amisnomer, reputedly coined on the spur of the moment in 1966 by Thomas Forcade when asked to describe the newly established news service, Underground Press Syndicate, of which he was an active member. The papers mentioned in this bibliography, except for the publications of the Weather Underground, were not published by secretive, covert organizations. Freedom of the press and of expression is protected by the First Amendment to the Constitution, although often only symbolically as the experience of the undergrounds will show, and most of the publications that fall into the “underground” described herein maintained public offices, contracted with commercial printers, and often used the U.S. Postal Service to distribute their publications.
Jacob Hibel, Daphne M. Penn and R. C. Morris
Social psychological perspectives on educational stratification offer explanations that bridge the macro and micro social worlds. However, while ethnoracial disparities in…
Abstract
Purpose
Social psychological perspectives on educational stratification offer explanations that bridge the macro and micro social worlds. However, while ethnoracial disparities in academic achievement are evident during the earliest grade levels, most social psychological research in this area has examined high school or college student samples and has used a black–white binary to operationalize race.
Design/methodology/approach
We use longitudinal structural equation models to examine links between academic self-efficacy beliefs and school performance among a national sample of diverse third- through eighth-grade students in the United States.
Findings
Contrary to hypotheses derived from the student identity literature, we find no evidence that elementary and middle school students from different ethnoracial backgrounds vary in the degree to which they selectively discount evaluative feedback in their academic self-efficacy construction, nor in the extent to which they demonstrate disrupted links between academic self-efficacy and subsequent academic performance.
Originality/value
The study examines the extent to which race-linked social psychological processes may be driving academic achievement inequalities during the primary schooling years.
Details
Keywords
Communications regarding this column should be addressed to Mrs. Cheney, Peabody Library School, Nashville, Tenn. 37203. Mrs. Cheney does not sell the books listed here. They are…
Abstract
Communications regarding this column should be addressed to Mrs. Cheney, Peabody Library School, Nashville, Tenn. 37203. Mrs. Cheney does not sell the books listed here. They are available through normal trade sources. Mrs. Cheney, being a member of the editorial board of Pierian Press, will not review Pierian Press reference books in this column. Descriptions of Pierian Press reference books will be included elsewhere in this publication.