Gregory Cermak - Academia.edu (original) (raw)
Papers by Gregory Cermak
Psychonomic Science, 1970
Psychonomic Science, 1970
Psychonomic Science, 1971
Cognitive Psychology, 1973
Perception & Psychophysics, 1977
In a sequential same-different comparison task, physically similar visual stimuli with the same i... more In a sequential same-different comparison task, physically similar visual stimuli with the same interpretation were more poorly discriminated than equally similar stimuli with different interpretations. Physical similarity of stimulus pairs was held constant by using parametrically controlled computer-generated visual forms and by using each pair of figures as both a sameinterpretation pair and as a different-interpretation pair. The interpretation variable used the ambiguous-figure properties of the forms. The two forms in each pair could be seen as representing the same object given one way of interpreting them; a second interpretation applied to only one member of the pair. The discrimination results held for interstimulus intervals of 300 msec and 13 sec. Similarities between the present studies and “categorical perception” studies are noted.
Subjective evaluations of IP telephony were collected while network performance was varied using ... more Subjective evaluations of IP telephony were collected while network performance was varied using an IP network emulator. Packet loss was set at 0%, 1%, or 8%. Mean one-way delay was set at 8 ms, 46 ms, or 156 ms (in addition to system delay of 90 ms). Delay variation (standard deviation) was set to 1 ms, 8 ms, or 17
Two studies examined the effect of B-frames on subjective quality of MPEG-2 video. One study used... more Two studies examined the effect of B-frames on subjective quality of MPEG-2 video. One study used consumer judgments in a variant of the standard CCIR Recommendation 500-5 procedure for collecting subjective evaluations. The other study used the judgments of a single expert in adjusting the bit rate necessary for MPEG-2 without B-frames to be subjectively equal to MPEG-2 with B-frames
We report a test of MPEG1 compressed video. Each of twelve short standard test scenes was process... more We report a test of MPEG1 compressed video. Each of twelve short standard test scenes was processed through seven versions of MPEG1 and through four comparison systems, yielding a total of 132 processed scenes. The MPEG1 versions were at bit rates of 0.9, 1.2, and 1.8 Mb/s. The comparison systems included VHS VCR and simulated cable TV. Consumers judged the
Consumers judged the quality of video images that had been compressed by an MPEG2 codec at the bi... more Consumers judged the quality of video images that had been compressed by an MPEG2 codec at the bit rates 3.0, 3.9, 5.3, and 8.3 Mb/s. The judgments were made in a standard testing laboratory. VHS and simulated cable analog systems also processed the same scenes for comparison. This study asked: (1) At what bit rate does MPEG2 video equal or
The study reported here maps three metrics of network performance into judged quality of videocon... more The study reported here maps three metrics of network performance into judged quality of videoconferencing: bandwidth, latency, and packet loss. A lab setup with a videoconferencing system and network emulator was used to manipulate the network parameters in a fractional factorial design. Pairs of non-expert judges held five-minute videoconferences and rated the quality of system performance for each combination of
Journal of The Acoustical Society of America, 1979
Two experiments examined the acoustical correlates of traffic sound aversiveness. In experimnet I... more Two experiments examined the acoustical correlates of traffic sound aversiveness. In experimnet I all pairs of 13 45-s traffic sound recordings were presented; subjects chose the sound of each pair to which they would rather be exposed and judged the relative similarity of the sounds. The energy equivalent sound level, Leq, accounted for choice and similarity judgments better than any other noise index, and there was no substantial improvement in ability to account for subjective judgments when other indices were used in conjunction with Leq. In experiment II subjects judged the same sounds which had been made equal in Leq level. Responses were nonrandom, showing that Leq is not the only subjectively important information in traffic sounds, but no acoustical measure employed in the study captured that information. Instead, two subjective measures of information content accounted best for the data of experiment II. Response data for the equal Leq sounds were less structured than for the sounds differing in Leq. The data of the two experiments were statistically related; it is argued that the data sets were related via the measure of information content. Experiment I replicated a previously reported study, while experiment II failed to replicate the results of a second study.
Broadcasting Ieee Transactions on, Mar 1, 2010
... Gregory W. Cermak and Kenneth A. Bollen General Motors Research Laboratories Warren, Michigan... more ... Gregory W. Cermak and Kenneth A. Bollen General Motors Research Laboratories Warren, Michigan ... 3. J. Mumpower, P. Middleton, RL Dennis, TR Stewart, V. Veirs, "Visual Air Quality Assessment: Denver Case Study," Presented at the Svm~osium on Plumes and Visibilitv. ...
Artifacts in digital video may occur intermittently due to transient events or states in a networ... more Artifacts in digital video may occur intermittently due to transient events or states in a network. Studying the subjective effect of intermittent artifacts in the lab can be difficult, especially when the intervals between artifacts are large. We assembled a consumer vocabulary of artifact types, then surveyed 200 digital cable users nationwide. The questionnaire was designed as a full factorial
Psychonomic Science, 1970
Psychonomic Science, 1970
Psychonomic Science, 1971
Cognitive Psychology, 1973
Perception & Psychophysics, 1977
In a sequential same-different comparison task, physically similar visual stimuli with the same i... more In a sequential same-different comparison task, physically similar visual stimuli with the same interpretation were more poorly discriminated than equally similar stimuli with different interpretations. Physical similarity of stimulus pairs was held constant by using parametrically controlled computer-generated visual forms and by using each pair of figures as both a sameinterpretation pair and as a different-interpretation pair. The interpretation variable used the ambiguous-figure properties of the forms. The two forms in each pair could be seen as representing the same object given one way of interpreting them; a second interpretation applied to only one member of the pair. The discrimination results held for interstimulus intervals of 300 msec and 13 sec. Similarities between the present studies and “categorical perception” studies are noted.
Subjective evaluations of IP telephony were collected while network performance was varied using ... more Subjective evaluations of IP telephony were collected while network performance was varied using an IP network emulator. Packet loss was set at 0%, 1%, or 8%. Mean one-way delay was set at 8 ms, 46 ms, or 156 ms (in addition to system delay of 90 ms). Delay variation (standard deviation) was set to 1 ms, 8 ms, or 17
Two studies examined the effect of B-frames on subjective quality of MPEG-2 video. One study used... more Two studies examined the effect of B-frames on subjective quality of MPEG-2 video. One study used consumer judgments in a variant of the standard CCIR Recommendation 500-5 procedure for collecting subjective evaluations. The other study used the judgments of a single expert in adjusting the bit rate necessary for MPEG-2 without B-frames to be subjectively equal to MPEG-2 with B-frames
We report a test of MPEG1 compressed video. Each of twelve short standard test scenes was process... more We report a test of MPEG1 compressed video. Each of twelve short standard test scenes was processed through seven versions of MPEG1 and through four comparison systems, yielding a total of 132 processed scenes. The MPEG1 versions were at bit rates of 0.9, 1.2, and 1.8 Mb/s. The comparison systems included VHS VCR and simulated cable TV. Consumers judged the
Consumers judged the quality of video images that had been compressed by an MPEG2 codec at the bi... more Consumers judged the quality of video images that had been compressed by an MPEG2 codec at the bit rates 3.0, 3.9, 5.3, and 8.3 Mb/s. The judgments were made in a standard testing laboratory. VHS and simulated cable analog systems also processed the same scenes for comparison. This study asked: (1) At what bit rate does MPEG2 video equal or
The study reported here maps three metrics of network performance into judged quality of videocon... more The study reported here maps three metrics of network performance into judged quality of videoconferencing: bandwidth, latency, and packet loss. A lab setup with a videoconferencing system and network emulator was used to manipulate the network parameters in a fractional factorial design. Pairs of non-expert judges held five-minute videoconferences and rated the quality of system performance for each combination of
Journal of The Acoustical Society of America, 1979
Two experiments examined the acoustical correlates of traffic sound aversiveness. In experimnet I... more Two experiments examined the acoustical correlates of traffic sound aversiveness. In experimnet I all pairs of 13 45-s traffic sound recordings were presented; subjects chose the sound of each pair to which they would rather be exposed and judged the relative similarity of the sounds. The energy equivalent sound level, Leq, accounted for choice and similarity judgments better than any other noise index, and there was no substantial improvement in ability to account for subjective judgments when other indices were used in conjunction with Leq. In experiment II subjects judged the same sounds which had been made equal in Leq level. Responses were nonrandom, showing that Leq is not the only subjectively important information in traffic sounds, but no acoustical measure employed in the study captured that information. Instead, two subjective measures of information content accounted best for the data of experiment II. Response data for the equal Leq sounds were less structured than for the sounds differing in Leq. The data of the two experiments were statistically related; it is argued that the data sets were related via the measure of information content. Experiment I replicated a previously reported study, while experiment II failed to replicate the results of a second study.
Broadcasting Ieee Transactions on, Mar 1, 2010
... Gregory W. Cermak and Kenneth A. Bollen General Motors Research Laboratories Warren, Michigan... more ... Gregory W. Cermak and Kenneth A. Bollen General Motors Research Laboratories Warren, Michigan ... 3. J. Mumpower, P. Middleton, RL Dennis, TR Stewart, V. Veirs, "Visual Air Quality Assessment: Denver Case Study," Presented at the Svm~osium on Plumes and Visibilitv. ...
Artifacts in digital video may occur intermittently due to transient events or states in a networ... more Artifacts in digital video may occur intermittently due to transient events or states in a network. Studying the subjective effect of intermittent artifacts in the lab can be difficult, especially when the intervals between artifacts are large. We assembled a consumer vocabulary of artifact types, then surveyed 200 digital cable users nationwide. The questionnaire was designed as a full factorial