Benefits of amplification for speech recognition in background noise

The purpose of the present study was to examine the benefits of providing audible speech to listeners with sensorineural hearing loss when the speech is presented in a background noise. Previous studies have shown that when listeners have a severe hearing loss in the higher frequencies, providing audible speech (in a quiet background) to these higher frequencies usually results in no improvement in speech recognition. In the present experiments, speech was presented in a background of multitalker babble to listeners with various severities of hearing loss. The signal was low-pass filtered at numerous cutoff frequencies and speech recognition was measured as additional high-frequency speech information was provided to the hearing-impaired listeners. It was found in all cases, regardless of hearing loss or frequency range, that providing audible speech resulted in an increase in recognition score. The change in recognition as the cutoff frequency was increased, along with the amount of audible speech information in each condition (articulation index), was used to calculate the "efficiency" of providing audible speech. Efficiencies were positive for all degrees of hearing loss. However, the gains in recognition were small, and the maximum score obtained by an listener was low, due to the noise background. An analysis of error patterns showed that due to the limited speech audibility in a noise background, even severely impaired listeners used additional speech audibility in the high frequencies to improve their perception of the "easier" features of speech including voicing

Associations between rural background and where South Australian general practitioners work

Objective: To determine the association between rural background on practice location of general practitioners (GPs) (rural or urban). Design: Comparison of data from two postal surveys. Subjects: 268 rural and 236 urban GPs practising in South Australia. Main outcome measures: Association between practice location (rural or urban) and demographic characteristics, training, qualifications, and rural background. Results: Rural GPs were younger than urban GPs (mean age 47 versus 50 years, P<0,01) and more likely to be male (81% versus 67%, P=0.001), to be Australian-born (72% Versus 61%, P=0,01), to have a partner (95% versus 85%, P= 0.001), and to have children (94% Versus 85%, P=0.001). Similar proportions of rural and urban GPs were trained in Australia and were Fellows of the Royal Australian College of General Practitioners, but more rural GPs were vocationally registered (94% versus 84%, P=0,001). Rural GPs were more likely to have grown up in the country (37% versus 27%, P= 0,02), to have received primary (33% versus 19%, P=0,001) and secondary (25% versus 13%, P=0,001) education there, and to have a partner who grew up in the country (49% Versus 24%, P=0.001). In multivariate analysis, only primary education in the country (odds ratio [OR], 2.43; 95% CI, 1.09-5.56) and partner of rural background (OR, 3.14; 95% CI, 1.96-5.10) were independently associated with rural practice. Conclusion: Our findings support the policy of promoting entry to medical school of students with a rural background and provide an argument for policies that address the needs of partners and maintain quality primary and secondary education in the country.

Content and context of monocular regions determine perceived depth in random dot, unpaired background and phantom stereograms

Perceived depth was measured for three-types of stereograms with the colour/texture of half-occluded (monocular) regions either similar to or dissimilar to that of binocular regions or background. In a two-panel random dot stereogram the monocular region was filled with texture either similar or different to the far panel or left blank. In unpaired background stereograms the monocular region either matched the background or was different in colour or texture and in phantom stereograms the monocular region matched the partially occluded object or was a different colour or texture. In all three cases depth was considerably impaired when the monocular texture did not match either the background or the more distant surface. The content and context of monocular regions as well as their position are important in determining their role as occlusion cues and thus in three-dimensional layout. We compare coincidence and accidental view accounts of these effects. (C) 2002 Elsevier Science Ltd. All rights reserved.

Background risk in generalized expected utility theory

In this paper, it is shown that, for a wide range of risk-averse generalized expected utility preferences, independent risks are complementary, contrary to the results for expected utility preferences satisfying conditions such as proper and standard risk aversion.

Perceptions of kanji learning strategies: Do they differ among Chinese character and alphabetic background learners

This study investigates three important issues in kanji learning strategies; namely, strategy use, effectiveness of strategy and orthographic background. A questionnaire on kanji learning strategy use and perceived effectiveness was administered to 116 beginner level, undergraduate students of Japanese from alphabetic and character backgrounds in Australia. Both descriptive and statistical analyses of the questionnaire responses revealed that the strategies used most often are the most helpful. Repeated writing was reported as the most used strategy type although alphabetic background learners reported using repeated writing strategies significantly more often than character background learners. The importance of strategy training and explicit instruction of fundamental differences between character and alphabetic background learners of Japanese is discussed in relation to teaching strategies. [Author abstract]