In this paper we describe work which characterises the effect of spatial factors on the segregation of concurrent sound sources. The results inform the operational requirements of virtual auditory displays required to render multiple, concurrent sound sources in terms of (i) minimum spacing between sources and (ii) identification of the principal acoustic directional cues exploited by the audit...

A visually reinforced operant procedure was employed to determine the behavioral thresholds of 6- to 7-month-old infants and adults for stimuli of various bandwidths and durations. Experiment 1 compared absolute thresholds for broadband and 1/3-octave filtered clicks and 300-msec noise bursts. For adult subjects, the difference in threshold for clicks and noise bursts was quite comparable in th...

Many sounds in the environment, including speech, are temporally dynamic. The auditory brainstem is exquisitely sensitive to temporal features of the incoming acoustic stream, and by varying the speed of presentation of these auditory signals it is possible to investigate the precision with which temporal cues are represented at a subcortical level. Therefore, to determine the effects of stimul...

Click fraud is a critical problem in pay-per-click advertising. While both service providers (SPs) and advertisers employ technologies to identify fraudulent clicks, prior work shows that they cannot be induced to make further improvements to their respective technologies. We consider the use of third-party investigation to address this problem and examine whether the responsibility of investig...

We describe a new type of threat to the Internet infrastructure, in the shape of a highly efficient but very well camouflaged click-fraud attack on the advertising infrastructure. The attack, which we refer to as a “badvertisement”, is described and experimentally verified on several prominent advertisement schemes. This stealthy attack can be thought of as a threatening mutation of spam and ph...

The feasibility of recording bone-conducted auditory brainstem responses (ABRs) to 500-Hz and 2000-Hz tone bursts and clicks was investigated in normal-hearing adults. For all 3 stimuli, responses were detectable in all subjects at 30 dB nHL. At 20 dB nHL, the tone burst responses were detectable in 80-87% of the subjects, demonstrating that even the responses to 500-Hz tone bursts were relativ...

An acoustic stimulus presented at the ear of an anesthetized cat evokes an electrical response from the auditory nerve of that animal. Our primary stimuli to date have been clicks produced by feeding rectangular pulses of duration 0. 1 msec into a PDR-10 earphone. These short stimuli evoke spike-like responses, which are detected by a fine wire electrode placed within the bullar cavity. Suitabl...

Human listeners can segregate sound sources based on differences in frequency content and timing. In addition, spatial separation has been shown to improve this ability. The work presented here is an attempt to characterise the effect of spatial factors on segregation when other distinguishing factors are either unavailable or unreliable. This is relevant to understanding how the auditory syste...

As an advertising tool, banners have been widely adopted by online marketers. However, because of low click-through rates, banners’ effectiveness has been questioned. A phenomenon called “banner blindness” suggests that salient stimuli, such as banners, are often missed by Internet users. This contradicts the distinctiveness view which argues that salient stimuli are more likely to attract user...

This study focused on the problem of estimating hearing sensitivity in newborns from auditory brainstem responses (ABRs) evoked by clicks and 500 Hz and 4000 Hz tonebursts presented by a bone-conduction (BC) oscillator. The effects of acoustic energy transmitted to the ear canal, gender, and ear differences were also investigated. ABR thresholds for BC stimuli were 56, 52, and 53 dB (re 1 micro...