Donald R. Williams

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Using the " belongs to " relation (∈) and quasi-coincidence with relation (q) between fuzzy points and fuzzy sets, the new concept of interval-valued (α, β)-fuzzy subgroup is introduced, where α and β are any of {∈, q, ∈ ∨q, ∈ ∧q} with α =∈ ∧q, and related properties are investigated. We provide characterizations of an interval-valued (∈, ∈ ∨q)-fuzzy(More)
Many self-employed workers return to the wage and salaried sector of the labor market after some time. It is possible that the self-employment spell will lead to lower earnings or earnings growth upon return, due to depreciation of firm or sector-specific human capital. Using longitudinal data from the NLS, this paper examines the effects of spells of(More)
Schizophrenia is a heterogeneous disorder in which psychiatric symptoms are classified into two general subgroups-positive and negative symptoms. Current antipsychotic drugs are effective for treating positive symptoms, whereas negative symptoms are less responsive. Since the neuropeptide oxytocin (OT) has been shown to mediate social behavior in animals(More)
In continuation of [13] we provide characterizations of an interval-valued (∈, ∈ ∨q)-fuzzy subgroup. We show that a proper interval-valued (∈, ∈)-fuzzy subgroupˆµF of group G such that # {Im(ˆ µF)} ≥ 3 can be expressed as the union of two proper non-equivalent interval-valued (∈, ∈)-fuzzy subgroup of group G. Finally, we also prove that ifˆµF is a proper(More)
Bureau of Labor Statistics, for providing the gross change data and to Thomas Nardone for helpful comments and additional data. Working papers of the Federal Reserve Bank of Cleveland are preliminary materials circulated to stimulate discussion and critical comment. The views stated herein are those of the author and not necessarily those of the Federal(More)
One of the most significant challenges currently facing the system engineering profession is devising procedures for improving the system software requirements development process. While many practitioners promote a variety of automated tools and mechanistic templates as the means to improved productivity, experience suggests the highest leverage lies in(More)
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