Towards Quality of Data Standards: Empirical Findings from XBRL

Certain data standards can help improve the quality of the data created according to the standards. But data standards do not always improve data quality. We introduce the notion of “quality of data standards” and argue that quality of data is affected by the quality of the standards used. We develop metrics for assessing quality of data standards. The metrics are evaluated empirically using company financial reports created using the eXtensible Business Reporting Language (XBRL) data standards. Our findings show the use frequency of standard data elements roughly follows a power law distribution. Tradeoffs exist between relevancy and completeness dimensions and between a single user perspective and user community perspective

A Two-Level Linear Dependent Type Theory

We present a type theory combining both linearity and dependency by stratifying typing rules into a level for logics and a level for programs. The distinction between logics and programs decouples their semantics, allowing the type system to assume tight resource bounds. A natural notion of irrelevancy is established where all proofs and types occurring inside programs are fully erasable without compromising their operational behavior. Through a heap-based operational semantics, we show that extracted programs always make computational progress and run memory clean. Additionally, programs can be freely reflected into the logical level for conducting deep proofs in the style of standard dependent type theories. This enables one to write resource safe programs and verify their correctness using a unified language

Microwave millisecond spike emission and its associated phenomena during the impulsive phase of large flares

A tentative model is proposed to account for some features of the microwave millisecond spike emission and its links with the physical processes of associated phenomena during the impulsive phase of large flares by comparing the optical, radio, and X-ray observations on May 16, 1981 to those on October 12, 1981