The relationship of word error rate to document ranking

This paper describes two experiments that examine the relationship of Word Error Rate (WER) of retrieved spoken documents returned by a spoken document retrieval system. Previous work has demonstrated that recognition errors do not significantly affect retrieval effectiveness but whether they will adversely affect relevance judgement remains unclear. A user-based experiment measuring ability to judge relevance from the recognised text presented in a retrieved result list was conducted. The results indicated that users were capable of judging relevance accurately despite transcription errors. This lead an examination of the relationship of WER in retrieved audio documents to their rank position when retrieved for a particular query. Here it was shown that WER was somewhat lower for top ranked documents than it was for documents retrieved further down the ranking, thereby indicating a possible explanation for the success of the user experiment

Properties of Pumice Lightweight Aggregate

The use of Lightweight concretes has gained acceptance and popularity world wide in the recent years in the construction and development of both the infrastructure and residential buildings. The properties of volcanic pumice lightweight aggregates obtained from Longonot in Mai Mahiu area in Kenya was experimentally investigated and this study presents the experimental results of the investigation. Three samples of the lightweight aggregates were investigated and their properties compared with those of the conventional normal aggregate. In this experimental investigation the physical and mechanical properties of the aggregates were investigated. Properties such as bulk density, water absorption, grading and aggregate impact crushing value were determined. Keywords: Pumice; Lightweight Aggregate, Bulk Density, Gradin

Fine structure of alpha decay in odd nuclei

Using an alpha decay level scheme, an explanation for the fine structure in odd nuclei is evidenced by taking into account the radial and rotational couplings between the unpaired nucleon and the core of the decaying system. It is stated that the experimental behavior of the alpha decay fine structure phenomenon is directed by the dynamical characteristics of the system.Comment: 8 pages, 3 figures, REVTex, submitted to Physical Review