Is there contextuality in behavioural and social systems?

Most behavioural and social experiments aimed at revealing contextuality are confined to cyclic systems with binary outcomes. In quantum physics, this broad class of systems includes as special cases Klyachko-Can-Binicioglu-Shumovsky-type, Einstein-Podolsky-Rosen-Bell-type and Suppes-Zanotti-Leggett-Garg-type systems. The theory of contextuality known as contextuality-by-default allows one to define and measure contextuality in all such systems, even if there are context-dependent errors in measurements, or if something in the contexts directly interacts with the measurements. This makes the theory especially suitable for behavioural and social systems, where direct interactions of 'everything with everything' are ubiquitous. For cyclic systems with binary outcomes, the theory provides necessary and sufficient conditions for non-contextuality, and these conditions are known to be breached in certain quantum systems. We review several behavioural and social datasets (from polls of public opinion to visual illusions to conjoint choices to word combinations to psychophysical matching), and none of these data provides any evidence for contextuality. Our working hypothesis is that this may be a broadly applicable rule: behavioural and social systems are non-contextual, i.e. all 'contextual effects' in them result from the ubiquitous dependence of response distributions on the elements of contexts other than the ones to which the response is presumably or normatively directed.

[The choice of surgical treatment for inguinal hernia].

Basing on the 30-year experience of prof. Yu.A. Nesterenko differential method of surgical treatment for inguinal hernias was worked out. The choice of surgical technique was based on the results of intra-operative revision of inguinal canal. Single-layer plasty of posterior wall was applied in case of insignificant destruction of tendinous structures; Shouldice plasty--in case of moderate changes; Moran plasty--in case of marked destruction, Lichtenstein plasty--in case of complete inguinal canal destruction. Analysis of long-term results showed low frequency of hernia relapses (1.4%) that can be compared with indices in specialized herniologic centers.

[The nearest and long-term results of surgical treatment of patients with scarry strictures of the esophagus after chemical burn].

Results of esophagoplasty (small intestine--5, stomach--35, colon--40) were studied in 80 patients with scarry stricture of the esophagus. The development of cancer in the burned esophagus was established in 3 out of 5 patients in 35-45 years after operation. Good and satisfactory results were obtained in 97.8% of the patients within the period from 5 to 17 years after gastro- and coloesophagoplasty. Unsatisfactory results were found in 3.2%. Total lethality after esophagoplasty was 12.5%.

[Characteristics of natural radionuclide distribution in different organs of plants growing on territory with increased radiation background].

We investigated wild-growing grassy plants such as Alhagi pseudalhagi, Zygophyllum, Juncus acutus and Argusia sibirica with the purpose of studying the mechanism of carry of radionuclides from ground in plants and an establishment most the common laws of distribution of radionuclides between different organs of plants. The results of the research show that the researched plants are mainly accumulated 40K. On a degree of accumulation, 226Ra occupies the second place, but 232Th doesn't participate almost in processes of carry from ground in plants. It is established that root systems of plants possesses unequal ability to absorb same radionuclides from the same ground. For example, the root system of Argusia sibirica is characterized by smaller ability to absorb 226Ra, but 40K is more accessible. It is shown that biological availability radionuclides in the given ground depends both on a kind of plants and on radionuclides. For example, Argusia sibirica, Zygophyllum show higher accumulating ability to 40K and in relation to 226Ra, Alhagi pseudalhagi and Juncus acutus are more sensitive. It is established that accumulating ability of stalks of different plants in relation to 40K are appreciably different. Distribution of radionuclides in seeds of plants has other character. Thus Alhagi pseudalhagi in the seeds had also certain amount of 232Th, and leaves Argusia sibirica in comparison with Zygophyllum have a high degree of accumulation as for 40K, so for 226Ra.

[Surgical treatment of cicatricial stricture of the esophagus and stomach after chemical burn].

The experience with treatment of 104 patients with burn cicatricial strictures of the esophagus and stomach is analyzed. Postoperative complications were seen in 28 (26.9%) patients. Hospital lethality was 12.5%. It is concluded that method of esophagoplasty in these patients should be selected individually.

Selective Influence and Response Time Cumulative Distribution Functions in Serial-Parallel Task Networks.

We analyze sets of mental processes, some of which are concurrent and some of which are sequential, under the assumption that the processes are partially ordered, that is, arranged in a directed acyclic network. Information about the process arrangement can be discovered by examining the effects on response time of selectively influencing process durations. Previous work has mainly focused on analyses of mean response times. Here we consider analyses based on cumulative distribution functions, for one of the major classes of directed acyclic networks, serial-parallel networks. When two processes are selectively influenced, patterns in the cumulative distribution functions can be used to test whether the processes are sequential or concurrent and whether the task network has AND gates or OR gates. Cumulative distribution functions are potentially more informative than means, and some previous results for means are shown to follow from our results for cumulative distribution functions. Copyright 2000 Academic Press.

Fechnerian metrics in unidimensional and multidimensional stimulus spaces.

A new theory is proposed for subjective (Fechnerian) distances among stimuli in a continuous stimulus space of arbitrary dimensionality. Each stimulus in such a space is associated with a psychometric function that determines probabilities with which it is discriminated from other stimuli, and a certain measure of its discriminability from its infinitesimally close neighboring stimuli is computed from the shape of this psychometric function in the vicinity of its minimum. This measure of discriminability can be integrated along any path connecting any two points in the stimulus space, yielding the psychometric length of this path. The Fechnerian distance between two stimuli is defined as the infimum of the psychometric lengths of all paths connecting the two stimuli. For a broad class of models defining the dichotomy of response bias versus discriminability, the Fechnerian distances are invariant under response bias changes. In the case in which physically multidimensional stimuli are discriminated along some unidimensional subjective attribute, a systematic construction of the Fechnerian metric leads to a resolution of the long-standing controversy related to the numbers of just-noticeable differences between isosensitivity curves. It is argued that for unidimensional stimulus continua, the proposed theory is close to the intended meaning of Fechner's original theory.

Detection of changes in speed and direction of motion: reaction time analysis.

Observers reacted to the change in the movement of a random-dot field whose initial velocity, V0, was constant for a random period and then switched abruptly to another value, V1. The two movements, both horizontally oriented, were either in the same direction (speed increments or decrements), or in the opposite direction but equal in speed (direction reversals). One of the two velocities, V0 or V1, could be zero (motion onset and offset, respectively). In the range of speeds used, 0-16 deg/sec (dps), the mean reaction time (MRT) for a given value of V0 depended on magnitude of V1-V0 only: MRT approximately r+c(V0)/magnitude of V1-V0 beta, where beta = 2/3, r is a velocity-independent component of MRT, and c(V0) is a parameter whose value is constant for low values of V0 (0-4 dps), and increases beginning with some value of V0 between 4 and 8 dps. These and other data reviewed in the paper are accounted for by a model in which the time-position function of a moving target is encoded by mass activation of a network of Reichardt-type encoders. Motion-onset detection (V0 = 0) is achieved by weighted temporal summation of the outputs of this network, the weights assigned to activated encoders being proportional to their squared spatial spans. By means of a "subtractive normalization," the visual system effectively reduces the detection of velocity changes (a change from V0 to V1) to the detection of motion onset (a change from 0 to V1-V0). Subtractive normalization operates by readjustment of weights: the weights of all encoders are amplified or attenuated depending on their spatial spans, temporal spans, and the initial velocity V0. Assignment of weights and weighted temporal summation are thought of as special-purpose computations performed on the dynamic array of activations in the motion-encoding network, without affecting the activations themselves.

[Study of the structure of human serum albumin, liberated from fatty acids, by a tritium marker method]. / Issledovanie struktury syvorotochnogo al'bumina cheloveka, svobodnogo ot zhirnykh kislot, metodom tritievoi metki.

To elucidate the natural fatty acids effect on the human serum albumin (HSA) structure a new method of tritium labelling was used. The main peculiarity of the method consists in the possibility to get information on the qualitative and quantitative amino acid composition of the surface layer of the protein globule at different conformational states of the globule. Defatted HSA was shown to be characterized a higher accessibility of Asx, Glx, Thr, Ser, Gly, Pro, Ile, Tyr residues while the other residues remain unchanged. Asx residues are characterized by the largest changes (about 8 folds). Full accessible protein surface during defatting increases from 39,000 to 48,000 A2. Fatty acids connected with albumin in the relation 1-3 moles/mol of protein are noted to be the factor increasing the globule compactness and stipulating for the conformational protein stability to warmth, urine and guanidine salts effect.

[Conformational transitions of human serum albumin depending on pH. Study using tritium markers]. / Zavisiashchie ot pH konformatsionnye perekhody syvorotochnogo al'bumina cheloveka. Issledovanie metodom tritievoi metki.

Accessible surfaces of the HSA molecule in N-, F- and B-forms were studied in the present work by tritium labelling method which allowed to obtain detailed information on N-F- and N-B-transitions. In was shown that the F-form in comparison top the N-form is characterized by more high accessibility of Ser, Ala, Ile, Tyr, Phe, His, Arg, Pro, Val and Phe residues and in the B-form Tyr, Ser, Arg, Gly, Ile, Phe and Pro residues turn to be highly accessible. Full accessible surfaces of protein molecule at N-F- and N-B-transitions increase respectively from 39,000 to 70,400 A2 and from 39,000 to 47,000 A2. Basing on the prevailing increase of hydrophobic residues accessibility it is supposed that the molecule expansion testifies the separation of the subunits forming the molecule.

Pitch motion with random chord sequences.

Perception of global pitch motion was studied through psychoacoustic experiments with random chord sequences. Chords contained either six or eight (fixed) tone elements, being sinusoidal, sawtooth-like, or Shepard tones, which were either on or off according to a probability controlled by the experimenter. Sequences of 2, 4, 5, or 8 chords were used. Identification by subjects of the perceived direction of overall pitch motion (up or down) was found to be well accounted for by a model in which the ultimate pitch motion percept is given by a sum of contributions from selected element transitions--that is, transitions between adjoining tone elements in successive time frames only. In its simplest form, this dipole contribution model has only one free parameter, the perceptual noise for an element transition, which was estimated for various acoustic tone representations and chord arrangements. Results of two experiments, which were carried out independently in two different laboratories, are reported.

[Determination of the accessible surface of lysozyme and human serum albumin molecules by the total tritium labeling method]. / Opredelenie dostupnoi poverkhnosti molekul lizotsima i syvorotochnogo al'bumina cheloveka metodom total'noi tritievoi metki.

Amino acids composing an accessible surface of lysozyme and human serum albumin (HSA) globules were determined by the total tritium labelling method. A good correlation between our data on the distribution of the tritium label for the lysozyme molecule and X-ray data on the tertiary structure for this macromolecule was received. Lysozyme was used as a standard for determining the accessible surface of the globule albumin. It was shown that the accessible surface of the albumin globule is substantially more hydrophobic (average accessible surface area of hydrophobic amino acids is 130 A2 in HSA and 20 A2 in lysozyme) than in lysozyme. The HSA molecule is characterized by high values of: the accessible surface area, the ratio of extended area to the folded one, and the surface roughness index. These data indicate that the HSA molecule is less compactly packed than lysozyme.

Motion direction identification in random cinematograms: a general model.

The cinematograms of 12 two-state elements arranged in the clock positions in space and in a sequence of adjacent 100-ms frames in time were used as stimuli. Some positions in each frame (or all 12 of them) could be labeled as "domain" ones, and every element that was T frames and S positions (clockwise or counterclockwise) apart from a domain element could repeat the latter's state with probability P. The probability of the rotation direction identification was obtained as a function of T, S, P, number of frames, and the domain positions selection scheme. A generalized version of the reversed phi phenomenon was obtained: if P less than .5, then the psychometric value lies below .5 level. All the data can be accounted for by a simple model according to which the choice of direction is based on the counts of the different types of dipoles, each type being characterized by the probability and the weight of its count: In most situations all dipoles but the shortest ones (connecting the neighboring elements of successive frames) can be ignored.

Reaction time to motion onset: local dispersion model analysis.

Data on the simple reaction time to motion onset presented in Ball and Sekuler [Psychol. Rev. 87, 435-469 (1980)] and Tynan and Sekuler [Vision Res. 20, 709-715 (1982)] are re-analysed on the basis of local dispersion model of motion detectability. According to this model the detectability at the moment t is determined by the mean value of the local dispersion function LD (t) within the interval (t-T, t), LD(t) being some measure of scattering (namely, running variance) of spatial positions passed through during the period (t-tau, t). Reaction time is assumed to be equal to the time that takes the detectability to reach some critical level plus constant execution time. Theoretical predictions fit the experimental data perfectly when two main parameters of the model, T/tau and tau are the same as were found appropriate in other, independent experiments on motion detection.