A simple model describes large individual differences in simultaneous colour contrast

The ability of observers to perceive distances and spatial relationships in outdoor environments was investigated in two experiments. In experiment 1, the observers adjusted triangular configurations to appear equilateral, while in experiment 2, they adjusted the depth of triangles to match their base width. The results of both experiments revealed that there are large individual differences in how observers perceive distances in outdoor settings. The observers' judgments were greatly affected by the particular task they were asked to perform. The observers who had shown no evidence of perceptual distortions in experiment 1 (with binocular vision) demonstrated large perceptual distortions in experiment 2 when the task was changed to match distances in depth to frontal distances perpendicular to the observers' line of sight. Considered as a whole, the results indicate that there is no single relationship between physical and perceived space that is consistent with observers' judgments of distances in ordinary outdoor contexts.

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Controlled Exertion of Force by Developmentally Delayed Young Men and Women

Perceptual and Motor Skills ◽

10.2466/pms.101.2.487-497 ◽

2005 ◽

Vol 101 (2) ◽

pp. 487-497

Author(s):

Yoshinori Nagasawa ◽

Shinichi Demura

Keyword(s):

Sex Differences ◽

Individual Differences ◽

Young People ◽

Voluntary Movement ◽

Large Individual ◽

Developmentally Delayed ◽

Men And Women ◽

Function Test ◽

Delayed Group ◽

Movement Function

Present purposes were to examine the characteristics of controlled force exertion in 28 developmentally delayed young people (14 men, 14 women), and sex differences compared to 28 normal young students (14 men, 14 women). The subjects matched their submaximal grip strength to changing demand values displayed in a bar chart on the display of a personal computer. The total sum of the differences between the demand value and grip exertion value for 25 sec. was used as an evaluation parameter for the test. The controlled force exertion was significantly poorer for the developmentally delayed group than for controls, and there were large individual differences. The developmentally delayed men scored poorer than women in coordination. Like the controls, the means between trials did not decrease significantly. For these developmentally delayed subjects, performance did not improve after only a few trials. The controlled force-exertion test is useful as a voluntary movement-function test for developmentally delayed subjects.

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Kinaesthesis: Its Measurement, Training and Relationship to Motor Control

The Quarterly Journal of Experimental Psychology Section A ◽

10.1080/14640748308402142 ◽

1983 ◽

Vol 35 (2) ◽

pp. 411-421 ◽

Cited By ~ 56

Author(s):

J. I. Laszlo ◽

P. J. Bairstow

Keyword(s):

Motor Control ◽

Individual Differences ◽

Motor Skills ◽

Age Groups ◽

Large Individual ◽

Motor Behaviour ◽

Perceptual Training ◽

Developmental Trends ◽

And Performance ◽

Improved Accuracy

This paper reviews studies which demonstrate the importance of kinaesthesis in the acquisition and performance of motor skills. A method of measuring kinaesthetic sensitivity in children and adults (recently developed) is briefly described. Developmental trends in kinaesthetic perception are discussed and large individual differences found within age groups. It was shown that kinaesthetically undeveloped children can be trained to perceive and memorize kinaesthetic information with greatly improved accuracy. Furthermore perceptual training facilitates the performance of a drawing skill. On the basis of these results an argument is made for the importance of kinaesthesis in skilled motor behaviour.

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Operators' Monitoring Patterns and Fault Recovery in the Supervisory Control of a Semi-Automatic Process

Proceedings of the Human Factors Society Annual Meeting ◽

10.1518/107118192786749775 ◽

1992 ◽

Vol 36 (15) ◽

pp. 1143-1147

Author(s):

John D. Lee ◽

Neville Moray

Keyword(s):

Individual Differences ◽

Supervisory Control ◽

Critical Role ◽

Normal Operation ◽

Large Individual ◽

Automatic Process ◽

Successful Implementation ◽

Control Actions ◽

Integrate Control ◽

And Control

Although technological innovations have changed the role of operators from active participants to supervisors of semiautomatic processes, an understanding of the cognitive demands of supervisory control has not kept pace. In particular, little is known about when, and how well, operators might intervene and switch control from automatic to manual. This research addresses this issue by monitoring the information use and control actions of operators of a simulated semiautomatic pasteurization plant. The results of this experiment shows that individual differences in operators” monitoring patterns during the normal operation of the plant correspond to differences in their ability to mitigate the effects of faults. Specifically, an operator who controls the plant well during both normal and fault conditions tends to observe the plant frequently, integrating control actions with other control actions, and does not fixate on narrow sub-systems of the plant. On the other hand, an operator who performs poorly when exposed to faults tends to observe the plant less often, fails to integrate control actions, and fixates attention on a narrow subset of plant variables. Although all operators interacted with the plant using the same interface and automation, large individual differences in the operators” monitoring patterns, and the associated differences in performance suggest that individuals” attitudes, motivation, and training may play a critical role in the successful implementation of automation.

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Perception of Slope and Distance in Photographs and in the Real World

Perception ◽

10.1068/v96l1012 ◽

1996 ◽

Vol 25 (1_suppl) ◽

pp. 33-33 ◽

Cited By ~ 4

Author(s):

I Davies ◽

J Howes ◽

J Huber ◽

J Nicholls

Keyword(s):

Individual Differences ◽

Power Function ◽

Real World ◽

Natural World ◽

Observation Point ◽

Scale Factor ◽

Large Individual ◽

The Real ◽

Series Of Experiments ◽

Natural Slopes

We report a series of experiments in which spatial judgments of the real world were compared with equivalent judgments of photographs of the real-world scenes. In experiment 1, subjects judged the angle from the horizontal of natural slopes. Judgments of slope correlated with true slope (r=0.88) but judgments were in general overestimates. Equivalent judgments of slope in photographs again correlated with true slope (r=0.91) but judgments tended to be overestimates for small angles (6°) and underestimates for larger angles (up to 25°). In experiment 2 slope judgments were made under laboratory conditions rather than in the natural world. The slopes, which were viewed monocularly, varied from 5° – 45°, and were either plain, or textured, or included perspective information (a rectangle drawn on the surface) or had both texture and perspective. Judgments were overestimates, but the correlation with true slope was high (r=0.97). Slopes with either texture or perspective were judged more accurately than plain slopes, but combining texture and perspective information conferred no further benefit. Judgment of the angle of the same slopes in photographs produced similar results, but the degree of overestimation (closer to the vertical) was greater than for the real slopes. In experiment 3, subjects either judged the distance of landmarks ranging from 200 m to 5000 m from the observation point, or judged distance to the landmarks in photographs. In both cases subjects' judgments were well described by a power function with exponents close to one. Although there are large individual differences, subjects' judgments of slope and distance are accurate to a scale factor, and photographs yield similar judgments to real scenes.

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Incubation of eggs of three species of Chelid tortoises, and notes on their embryological development

Australian Journal of Zoology ◽

10.1071/zo9680749 ◽

1968 ◽

Vol 16 (5) ◽

pp. 749 ◽

Cited By ~ 20

Author(s):

J Goode ◽

J Russell

Keyword(s):

Individual Differences ◽

The Other ◽

Large Individual ◽

Embryological Development ◽

Natural Conditions ◽

Early Embryos ◽

Incubation Periods ◽

The Mean ◽

Main Factors ◽

Chelodina Longicollis

Incubation periods and nest contents of three species of chelid tortoises in northern Victoria were recorded. Mean incubation period for eggs of Emydura macquari (Cuvier) was 75 days and average number of eggs per nest was 15.7; for Chelodina longicollis (Shaw), 138 days and 10.7 eggs per nest; for Chelodina expansa Gray, normally exceeding 324 days and 15.4 eggs per nest. In abnormal seasons C. expansa hatchlings may emerge from the nest in less than 193 days or more than 522 days after eggs were deposited. Eggs artificially incubated at 30�C consistently develop more quickly than those at lower temperatures under natural conditions. In the field nest temperatures closely approximate the mean daily air temperature. Embryos of C. expansa are tolerant to nest temperatures ranging from 4.9�C minimum to 29.6�C maximum. The other species are subject to variations of about 15 degC with up to 8.5 degC variation being recorded in 1 day. Development of early embryos approximated that recorded for cryptodire tortoises. However, there are large individual differences in the period of incubation needed for specific stages to be reached, especially between embryos of the short-necked and long-necked species of these pleurodire tortoises. It is suggested that differences in the anatomy of their eggs are the main factors in the different incubation periods between short-necked and long-necked species.

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Distal similarity, shape referents, subjective world, and redundancy

Behavioral and Brain Sciences ◽

10.1017/s0140525x98251259 ◽

1998 ◽

Vol 21 (4) ◽

pp. 470-470

Author(s):

Hannes Eisler

Keyword(s):

Individual Differences ◽

Crucial Role ◽

Large Individual ◽

Subjective Space

The concept of distal similarity that plays a crucial role in Edelman's theory of representation is called into question in this commentary on theoretical as well as empirical grounds. A possible confusion between shape and (knowledge of) its referent, the problem of the subjective world, redundancy, and large individual differences in subjective space encountered in contrived universes are discussed.

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MINERAL-DEFICIENT DIETS AND THE PIG'S ATTRACTION TO BLOOD: IMPLICATIONS FOR TAIL-BITING

Canadian Journal of Animal Science ◽

10.4141/cjas87-096 ◽

1987 ◽

Vol 67 (4) ◽

pp. 909-918 ◽

Cited By ~ 48

Author(s):

DAVID FRASER

Keyword(s):

Individual Differences ◽

Control Diet ◽

Growing Pigs ◽

Iodized Salt ◽

Abnormal Behavior ◽

Large Individual ◽

Mineral Deficiency ◽

Pronounced Increase ◽

Mineral Supplements ◽

Tail Biting

In two experiments, individually penned growing pigs were exposed daily to two "tail models" (lengths of cotton cord about the size of a pig's tail), one of which had been impregnated with pigs' blood. When fed a balanced "control" diet, the pigs chewed significantly more on the blood-covered model than on the plain one, but with large individual differences between animals. Four weeks of receiving a diet lacking all mineral supplements (iodized salt, dicalcium phosphate, limestone, iron, zinc, manganese, copper, and selenium) caused a pronounced increase in chewing the blood-covered model, and 4 wk of recovery on the control diet reduced, but did not completely eliminate, the enhanced attraction to blood. In a second experiment, a similar heightened response to blood was produced by omitting only iodized salt from the diet, whereas omission of all other mineral supplements led to a much smaller and statistically non-significant change. Although the causes of tail-biting are undoubtedly complex, the results suggest that heightened appetite for salt could make pigs particularly attracted to pen-mates with injured tails. Key words: Pigs, tail-biting, abnormal behavior, salt, sodium, mineral deficiency

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The Importance of Nongenetic Influences on Romantic Love Styles: A Twin-Family Study

Psychological Science ◽

10.1111/j.1467-9280.1994.tb00624.x ◽

1994 ◽

Vol 5 (5) ◽

pp. 268-274 ◽

Cited By ~ 31

Author(s):

Niels G. Waller ◽

Phillip R. Shaver

Keyword(s):

Individual Differences ◽

Family Environment ◽

Family Study ◽

Personality Development ◽

Model Fitting ◽

Romantic Love ◽

Shared Environment ◽

Large Individual ◽

Love Styles ◽

The Common

Research in several disciplines reveals large individual differences in orientations to romantic love, yet the origins of the differences have been unclear In this first behavior genetic study of romantic love, biometric model fitting reveals that in contrast to other personality and attitude domains, where genetic factors account for approximately 50% of the reliable variance and shared environment has little effect, individual differences in romantic love are due almost exclusively to environment Moreover, the common family environment plays a sizable role in determining love styles, a finding compatible with theories stressing the importance of family inter-actions in personality development

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The Golden Section and the Aesthetics of Form and Composition: A Cognitive Model

Empirical Studies of the Arts ◽

10.2190/wwcr-vwhv-2y2w-91ee ◽

1997 ◽

Vol 15 (2) ◽

pp. 209-232 ◽

Cited By ~ 31

Author(s):

I. C. McManus ◽

P. Weatherby

Keyword(s):

Individual Differences ◽

Fuzzy Set ◽

Golden Section ◽

Cognitive Model ◽

Population Level ◽

Individual Variability ◽

Large Individual ◽

Powerful Method ◽

Preference Functions ◽

Geometric Objects

Previous work on the aesthetics of simple figures such as rectangles and triangles, as well as on the aesthetics of color, suggests that although there are clear population level preferences, there are also large individual differences which are temporally stable, and which any adequate theoretical analysis must take into account. Data presented here show similar phenomena in a related problem in composition—where to place an object within the frame of a picture to produce the optimal aesthetic effect. A novel and powerful “method of randomized paired comparisons” first showed that there are overall population level preferences, with objects being placed preferentially at the two golden sections horizontally, and between the two golden sections vertically. As in the studies of simple figures and colors, there are large individual differences. A cognitive model of “sensory aesthetics” is proposed in which continua of any type (space, geometric objects, colors, or whatever), are described categorically, usually in terms of words such as “square,” “rectangle,” “line,” etc., each of which is a fuzzy set. Preference functions are then derived from the union and intersection of the fuzzy set functions, which differ between individuals as their categories differ or as they prefer objects which are prototypical, or are at the boundaries between prototypes. There is therefore wide inter-individual variability.

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