Commentary on ‘Science,Measurement, and Validity: Is Completion of Samuel Messick's Synthesis Possible?’ by Keith A. Markus

Social Indicators Research -     

Private Bag: More on the Myths That Population and Immigration Are No Longer Problems

Population and Environment -     

Open Tertiary Education in Australia

The draft report of the Committee on Open University, Open Tertiary Education, is criticized on the grounds that it is overly conservative and makes little contribution to the opening up of tertiary education in Australia. The problems inherent in government committees, particularly in the field of education, are considered. Using the data provided in the report, the current closed system of tertiary education is criticized and a number of proposals, alternative to those made in the report, are presented for consideration.     

An Evaluation of Stimulus Preference Assessment Methodology in Organizational Behavior Management

The organizational behavior management literature has yielded few stimulus preference assessment methodologies for use with employees. The current investigation compared three preference assessments (ranking, survey, and multiple stimulus without replacement procedures) found in the organizational behavior management literature for their ability to predict reinforcers for direct care staff members’ behavior. In the first experiment all assessments were effective for predicting reinforcers, but the results were limited by a lack of control items in the assessment. In the second experiment the survey and ranking assessments both proved to be effective for identifying reinforcers and neutral or ineffective stimuli. Implications of these results and directions for future research are discussed.     

An International Pooled Analysis for Obtaining a Benchmark Dose for Environmental Lead Exposure in Children

Lead is a recognized neurotoxicant, but estimating effects at the lowest measurable levels is difficult. An international pooled analysis of data from seven cohort studies reported an inverse and supra‐linear relationship between blood lead concentrations and IQ scores in children. The lack of a clear threshold presents a challenge to the identification of an acceptable level of exposure. The benchmark dose (BMD) is defined as the dose that leads to a specific known loss. As an alternative to elusive thresholds, the BMD is being used increasingly by regulatory authorities. Using the pooled data, this article presents BMD results and applies different statistical techniques in the analysis of multistudy data. The calculations showed only a limited variation between studies in the steepness of the dose‐response functions. BMD results were quite robust to modeling assumptions with the best fitting models yielding lower confidence limits (BMDLs) of about 0.1–1.0 μ g/dL for the dose leading to a loss of one IQ point. We conclude that current allowable blood lead concentrations need to be lowered and further prevention efforts are needed to protect children from lead toxicity.     

Systematic analysis of multiple voting rules

For a class of voting rules, which includes Approval and Cumulative Voting, it is shown how to find and analyze all possible outcomes that arise with a specified profile, and, conversely, how to start with a potential region and determine whether there exist supporting profiles. The geometry of these regions is determined by the “Reversal symmetry” portion of a profile; i.e., components of the A\succ B\succ C, C\succ B\succ A{A\succ B\succ C, C\succ B\succ A} type.     

String decomposition of full-period tausworthe sequences

Because of their nice properties relative to the frequency of occurrence of n-tuples, Tausworthe sequences have been used frequently in recent years as the basis for random number generators. This paper describes a similar result relative to the frequency of occurrence of maximal-length strings of like bits. In particular, for any full-period Tausworthe sequence, the distribution of string lengths is precisely equal to the expected distribution of string lengths for a truly random bit sequence of comparable size.