bluuebunny/crossref_metadata_2025 huggingface dataset:
Femtosecond ultrasonic spectroscopy using a piezoelectric nanolayer: Hypersound attenuation in vitreous silica films
Authors: Wen Yu-Chieh , Guol Shi-Hao , Chen Hung-Pin , Sheu Jinn-Kong , Sun Chi-Kuang
Published: August 2011

We report ultra-broadband ultrasonic spectroscopy with an impedance-matched piezoelectric nanolayer, which enables optical generation and detection of a 730-fs acoustic pulse (the width of ten lattice constants). The bandwidth improvement facilitates THz laser ultrasonics to bridge the spectral gap between inelastic light and x-ray scatterings (0.1-1 THz) in the studies of lattice dynamics. As a demonstration, this method is applied to measure sound attenuation α in a vitreous SiO2 thin film. Our results extend the existing low-frequency data obtained by ultrasonic-based and light scattering methods and also show a α∝ f2 behavior for frequencies f up to 650 GHz.
Dangerous dining: surface foraging of North Atlantic right whales increases risk of vessel collisions
Authors: Parks Susan E. , Warren Joseph D. , Stamieszkin Karen , Mayo Charles A. , Wiley David
Published: August 2011

North Atlantic right whales are critically endangered and, despite international protection from whaling, significant numbers die from collisions with ships. Large groups of right whales migrate to the coastal waters of New England during the late winter and early spring to feed in an area with large numbers of vessels. North Atlantic right whales have the largestper capitarecord of vessel strikes of any large whale population in the world. Right whale feeding behaviour in Cape Cod Bay (CCB) probably contributes to risk of collisions with ships. In this study, feeding right whales tagged with archival suction cup tags spent the majority of their time just below the water's surface where they cannot be seen but are shallow enough to be vulnerable to ship strike. Habitat surveys show that large patches of right whale prey are common in the upper 5 m of the water column in CCB during spring. These results indicate that the typical spring-time foraging ecology of right whales may contribute to their high level of mortality from vessel collisions. The results of this study suggest that remote acoustic detection of prey aggregations may be a useful supplement to the management and conservation of right whales.
Identification of Epstein–Barr virus-infected CD27+ memory B-cells in liver or stem cell transplant patients
Authors: Ito Yoshinori , Kawabe Shinji , Kojima Seiji , Nakamura Fumihiko , Nishiyama Yukihiro , Kaneko Kenichiro , Kiuchi Tetsuya , Ando Hisami , Kimura Hiroshi
Published: August 2011

To analyse the phenotype of Epstein–Barr virus (EBV)-infected lymphocytes in EBV-associated infections, cells from eight haematopoietic stem cell/liver transplantation recipients with elevated EBV viral loads were examined by a novel quantitative assay designed to identify EBV-infected cells by using a flow cytometric detection of fluorescent in situ hybridization (FISH) assay. By this assay, 0.05–0.78 % of peripheral blood lymphocytes tested positive for EBV, and the EBV-infected cells were CD20+ B-cells in all eight patients. Of the CD20+ EBV-infected lymphocytes, 48–83 % of cells tested IgD positive and 49–100 % of cells tested CD27 positive. Additionally, the number of EBV-infected cells assayed by using FISH was significantly correlated with the EBV-DNA load, as determined by real-time PCR (r
2 = 0.88, P<0.0001). The FISH assay enabled us to characterize EBV-infected cells and perform a quantitative analysis in patients with EBV infection after stem cell/liver transplantation.
Interactions of temperature and nutrient changes: effects on phytoplankton in the Piburger See (Tyrol, Austria)
Authors: THIES H. , TOLOTTI M. , NICKUS U. , LAMI A. , MUSAZZI S. , GUILIZZONI P. , ROSE N. L. , YANG H.
Published: August 2011

1. Contemporary limnological and palaeolimnological data from Piburger See (Eastern Alps, Austria) allowed the reconstruction of its trophic state since the late 19th century and the assessment of changes in phytoplankton biomass and species composition in relation to selected environmental parameters.

2. A radiometrically dated sediment core from Piburger See was analysed for geochemical parameters, spheroidal carbonaceous particles (SCPs), bacterial and algal pigments, and diatoms. The low SCP sediment inventory assigns Piburger See to the ‘cleaner’ sites in Europe with respect to fossil‐fuel related air pollution. The sedimentary pigment and diatom record reveals moderate eutrophication during the 20th century, followed by a slow re‐oligotrophication since the mid‐1980s because of lake restoration starting in 1970.

3. Epilimnetic temperature for Piburger See was reconstructed using air temperature records. A pronounced temperature increase has been recorded during the mid‐1940s and since the late‐20th century, both promoting algal growth and changes in species composition (e.g. increase in centric diatoms and recent bloom of Asterionella formosa).

4. Climate scenarios project additional substantial warming for this mountain lake by the end of the 21st century which will be most pronounced during the growing season. The predicted change in lake water temperature and thermal dynamics represents a key driver for the trophic and ecological status of Piburger See in the future.
Possible Involvement of IL‐21 and IL‐10 on Salivary IgA Levels in Chronic Periodontitis Subjects
Authors: Napimoga M. H. , Nunes L. H. A. C. , Maciel A. A. B. , Demasi A. P. D. , Benatti B. B. , Santos V. R. , Bastos M. F. , de Miranda T. S. , Duarte P. M.
Published: August 2011

Specific cytokines and the costimulatory protein CD40 play role in inducing immunoglobulin (Ig)A production by B cells in the humoral immune response. However, to date, the role of these mediators was not investigated in chronic periodontitis. Therefore, the aim of this study was to assess the local levels of interleukin (IL)‐21, IL‐21 receptor (IL‐21R), IL‐4, IL‐10 and CD40 ligand (CD40L) on chronic periodontitis subjects and their relationship with the salivary levels of IgA. Gingival biopsies and un‐stimulated saliva were collected from chronic periodontitis (n = 15) and periodontally healthy (n = 15) subjects. The mRNA levels of IL‐4, IL‐10, IL‐21, IL‐21R, CD40L in the gingival biopsies were evaluated by quantitative real‐time polymerase chain reaction. The salivary levels of IgA and the levels of IL‐4 and IL‐10 in the gingival biopsies were analyzed by ELISA. The mean levels of IgA were significantly higher in the chronic periodontitis compared to periodontally healthy group (P < 0.05). The mRNA levels for IL‐21 was higher (P < 0.05) in the chronic periodontitis when compared to the healthy group. However, the expression of IL‐21R and CD40L did not differ between groups. The IL‐10 was significantly elevated at mRNA and protein levels in chronic periodontitis when compared to periodontally healthy group (P < 0.05). Conversely, the mRNA levels as well as the protein amount of IL‐4 were significantly lower (P < 0.05) in chronic periodontitis than healthy ones. In conclusion, the upregulation of IL‐21 and IL‐10 and downregulation of IL‐4 in periodontitis tissues may be collectively involved in the increased levels of salivary IgA in chronic periodontitis subjects.
PRINCIPLES FOR THE IMPLEMENTATION OF A PEDESTRIAN PLAN IN MEDIUM SIZE CITIES
Authors: Alves Fernando Manuel Brandão , Ramalho António Manuel Leite
Published: August 2011

In order to contribute to the effective humanization of the contemporary city and in line with the sustainability of urban areas, this paper focuses on primary pedestrian areas aiming to investigate and demonstrate the benefits of organization and the essential conditions of implementing “pedestrian networks”.

The realization of its qualifying character in the urban environment should specify:

The challenge of reinterpreting the idea of the city, due to the transformation of associated “urban forms” and “lifestyles”;

The need to structure the territory, in order to promote the understanding and ownership of the different places that compose a city;

The ability to generate synergies, as a means of affirming the “local” in the context of the “global” opportunities and threats.

It is, therefore, disciplinary useful to test a methodological urban planning “process” with the aim to design and manage “pedestrian networks”, applicable in a range of cities considered of medium size, according to the European classification mainly based on population criteria.
ILLOCUTION, SILENCING AND THE ACT OF REFUSAL
Authors: MIKKOLA MARI
Published: August 2011

Rae Langton and Jennifer Hornsby argue that there may be a free‐speech argument against pornography, if pornographic speech has the power to illocutionarily silence women: women's locution ‘No!’ that aims to refuse unwanted sex may misfire because pornography creates communicative conditions where the locution does not count as a refusal. Central to this is the view that women's speech lacks uptake, which is necessary for illocutionary acts like that of refusal. Alexander Bird has critiqued this view by arguing that uptake is not necessary for the illocutionary act of refusal. The Hornsby‐Langton view, then, is philosophically indefensible. Here I defend the philosophical cogency of the Hornsby‐Langton approach.
Auditory Brainstem Response (ABR) Abnormalities Across the Life Span of Rats Prenatally Exposed to Alcohol
Authors: Church Michael W. , Hotra John W. , Holmes Pamela A. , Anumba Jennifer I. , Jackson Desmond A. , Adams Brittany R.
Published: August 2011

Background:  Fetal alcohol syndrome (FAS) is a leading cause of neurodevelopmental impairments (NDIs) in developed countries. Sensory deficits can play a major role in NDI, yet few studies have investigated the effects of prenatal alcohol exposure on sensory function. In addition, there is a paucity of information on the lifelong effects of prenatal alcohol exposure. Thus, we sought to investigate the effects of prenatal alcohol exposure on auditory function across the life span in an animal model. Based on prior findings with prenatal alcohol exposure and other forms of adverse prenatal environments, we hypothesized that animals prenatally exposed to alcohol would show an age‐dependent pattern of (i) hearing and neurological abnormalities as postweanling pups, (ii) a substantial dissipation of such abnormalities in young adulthood, and (iii) a resurgence of such abnormalities in middle‐aged adulthood.

Methods:  Pregnant rats were randomly assigned to an untreated control (CON), a pair‐fed control (PFC), or an alcohol‐treated (ALC) group. The ALC dams were gavaged with 6 mg/kg alcohol daily from gestation day (GD) 6 to 21. The PFC dams were gavaged daily from GD6 to GD21 with an isocaloric and isovolumetric water‐based solution of maltose‐dextrins and pair‐fed to the ALC dams. The CON dams were the untreated group to which the ALC and CON groups were compared. Hearing and neurological functions in the offspring were assessed with the auditory brainstem response (ABR) at the postnatal ages of 22, 220, and 520 days.

Results:  In accord with our hypothesis, ABR abnormalities were first observed in the postweanling pups, largely dissipated in young adulthood, and then resurged in middle‐aged adulthood. This age‐related pattern suggests that the ALC pups had a developmental delay that dissipated in young adulthood and an enhanced age‐related deterioration that occurred in middle‐aged adulthood. Such a pattern is consistent with the fetal programming hypothesis of adult‐onset diseases (the Barker hypothesis).

Conclusions:  Our findings have important clinical implications for the assessment and management of (i) childhood hearing disorders and their comorbidities (i.e., speech‐and‐language, learning, and attention deficit disorders) and (ii) enhanced age‐related hearing and neurological degeneration in middle‐aged adulthood that can result from prenatal alcohol exposure. We recommend hearing evaluation be a part of any long‐term follow‐up for FAS patients and patients exposed to any adverse prenatal environment.
Evaluation of the Effects of Urotensin II and Soluble Epoxide Hydrolase Inhibitor on Skin Microvessel Tone in Healthy Controls and Heart Failure Patients
Authors: Tran Lavinia , Kompa Andrew R. , Wang Bing H. , Krum Henry
Published: August 2011

Introduction: Urotensin II (UII) is a potent vasoactive peptide that exerts differential effects on heart failure (HF) patients compared to health controls. However, the mechanism of action remains unclear. The role of soluble epoxide hydrolase (sEH) as a mediator of UII in the vasculature has not been explored. Aims: The aim of this study was to examine the effect of UII in the presence and absence of sEH inhibitor AUDA on skin microvessel tone in HF patients and healthy controls using iontophoresis and laser Doppler velocimetry. UII (10−7 M) and AUDA (10−10, 10−7, and 10−5 M) were administered to the forearm of participants by iontophoresis for 30 seconds. Laser Doppler velocimetry was performed for 5 minutes to measure flux through the subcutaneous blood vessels. Response (flux) was measured for 5 minutes per concentration with 25 continuous scans. Results: UII increased flux in healthy controls by 39% (P < 0.05) and increased flux in HF patients by 6% (ns). AUDA (10−10 and 10−7 M) administration further decreased flux by 115% (P < 0.05) and 255% (P < 0.0001), respectively in healthy controls. In HF patients, AUDA (10−10, 10−7, and 10−5 M) further increased flux by 77% (P < 0.05), 67% (P < 0.01), and 100% (P < 0.05), respectively. AUDA alone at 10−7 M increased flux in both groups by 31% (healthy controls, P < 0.05) and 36% (HF, P < 0.01). Conclusion: Taken together, the presence of HF appeared to abrogate the vasodilator responsiveness of sEH inhibitor. These results suggest an important role for both UII and sEH in vascular regulation and that sEH may be involved in mediating UII effects. Furthermore, the study highlights the therapeutic potential of sEH inhibitors for the treatment of HF.
A PSYCHOLOGICAL STUDY OF TYPOGRAPHY
Authors: BURT CYRIL , COOPER W. F. , MARTIN J. L.
Published: August 2011

Abstract. A wide variety of type‐faces have now become available for books and journals. It therefore seemed desirable to investigate (A) the legibility and (B) the aesthetic merits of those in more frequent use.

Using tests of speed and comprehension, we have studied the influence of type‐face, boldness, size, interlinear spacing, length of line, and width of margin on legibility both with children and with adults. The results have furnished provisional norms for children's reading books and for scientific journals such as the present.

Factorial methods, supplemented by an analysis of introspections, appear to yield a classification of both readers and type faces based on aesthetic preference; and the data incidentally obtained throw considerable light on the reasons for such preferences.
THE COMPARISON OF FREQUENCIES IN MATCHED SAMPLES
Authors: Stuart Alan
Published: August 2011

For purposes of statistical comparison, matched samples are in general more accurate than unmatched. In testing the statistical significance of the results, it is essential to take into account the gain in accuracy, due to the matching. The following paper indicates how this can be done in the case of attributes.
THE RESCALING OF TEACHERS' ESTIMATES
Authors: Pilliner A. E. G.
Published: August 2011

Four methods of rescaling are described, and their advantages and disadvantages for different types of problem are discussed in detail. Each method has been applied to data obtained from a complete age‐group of over 900 children. So far as they go, the results clearly show that for general purposes the method based on the ‘orthogonal mean square regression line’ (i.e. on the principal axis) of the distribution, which is in fact the method in general use, is the most efficient.
TAYLOR ON ‘LAW’ AND ‘THEORY’ IN PSYCHOLOGY
Authors: Pilkington G. W.
Published: August 2011

This paper criticizes the ideal of ‘law’ and ‘theory’ in psychology put forward by Taylor. It is suggested that his first two requirements for ‘genuine’ scientific laws are so stringent as to be unrealistic, and that the second two, though sound in principle, are too vague for it to be clear what particular psychological laws they are intended to exclude. Finally, reasons are adduced for rejecting what Peters has called ‘dogmatic methodism’, of which Taylor's proposals are typical examples.
THE EFFECT OF ONE STIMULUS ON THE THRESHOLD FOR ANOTHER: AN APPLICATION OF SIGNAL DETECTABILITY THEORY1
Authors: Treisman Michel
Published: August 2011

If an accessory stimulus regularly precedes a critical stimulus at a fixed inter‐stimulus interval then the shorter the interval the lower the threshold for the critical stimulus. Three hypotheses which might explain this are discussed, and two experiments described. Experiment 1 shows that varying the intensity of an accessory stimulus does not affect the extent of the threshold fall it produces. Experiment 2 confirmed a prediction that randomizing inter‐stimulus intervals over a small range would allow the threshold to fall as the mean inter‐stimulus interval decreased at long mean intervals but not at short ones. Taken with earlier results, these experiments indicate that the subject lowers his threshold during a range of time about the end of the inter‐stimulus interval in which he expects that the stimulus may occur. It is also shown that the extent of the fall in threshold is inversely proportional to the length of this range of expectation, and that the latter appears to be directly proportional to the duration of the inter‐stimulus interval.

This variation in threshold level is considered in terms of the model of the threshold provided by signal detectability theory. It is shown that the threshold falls are due to changes in the criterion computed by the subject, rather than in the sensory noise. This model is also successfully used to predict the extent of the shifts in detection rate that occur as the inter‐stimulus interval alters, on the assumption that subjects attempt to keep their false positive rates constant. Finally it is suggested that in computing the appropriate criterion for each inter‐stimulus interval the subject uses a simple approximate method rather than the more complex exact method.
A LEARNING MODEL FOR FORCED‐CHOICE DETECTION EXPERIMENTS1
Authors: Atkinson R. C. , Kanchla R. A.
Published: August 2011

Several signal detection experiments employing a forced‐choice procedure are analysed in terms of a model that incorporates two distinct processes: a sensory process and a decision process. The sensory process specifies the relation between external signal events and hypothesized sensory states of the subject. The decision process specifies the relation between the sensory states and the observable responses of the subject. The sensory process is assumed to be fixed throughout an experiment, whereas the decision process is viewed as varying from trial to trial as a function of the particular sequence of preceding events. The changes in the decision process are assumed to be governed by a simple stochastic learning model. There are several ways of formulating the learning model and the experiments reported here were designed to select among these alternative approaches. The empirical results favour a linear‐operator process with trial‐to‐trial changes in response probabilities that are a function not only of the signal and information events, but also of the particular sequence of sensory states activated.
FLOW GRAPH REPRESENTATION OF MOTIVATIONAL SYSTEMS1
Authors: McFarland D. J.
Published: August 2011

The flow graph method of representing systems is described and a guide to flow graph construction is given. A system which might be involved in the control of drinking is used as an example of the ‘black box’ approach to flow graph construction, and this example is elaborated in sections dealing with procedures leading to simplification and quantification. The particular advantages of a flow graph representation of motivational systems are discussed and are seen to lie in those properties of the approach which afford precise description and measurement of the important variables in a biological system.
THE EFFECT OF CRITERION SCORE GROUPING UPON ITEM PARAMETER ESTIMATION
Authors: Baker Frank B.
Published: August 2011

The differential effect of three grouping procedures upon the first two moments of the sampling distributions of the parameters X50 and β of the item characteristic curve were investigated empirically. The results of the study indicated that differences in the variances of β and X50 as well as in the bias of X50 could be attributed to differences in grouping procedures. Item parameter estimates possessing the minimum bias and variance within the study were those yielded by the grouping procedure which used equally spaced criterion score intervals and the same number of subjects within each interval.
APL: A COMPUTING LANGUAGE DESIGNED FOR THE USER
Authors: Hunka S.
Published: August 2011

Traditionally computer languages have been thought of only in the context of communications with a computer. Most languages in common use today are still more dependent upon machine design characteristics than the needs of the user. APL, designed by K. E. Iverson, is a new language equally useful for purposes of communicating with a computer as it is for use in the classroom. This powerful language can be learned easily and applied to a wide range of problems.
LATENCY AND RELATIVE FREQUENCY OF RESPONSE IN PSYCHOPHYSICAL DISCRIMINATION
Authors: Pike A. R.
Published: August 2011

The relation between response latency and probability is discussed with particular reference to differences between mean times for correct and incorrect responses in difficult two‐choice discriminations. The predictions of some finite Markov chain models for this situation are considered, and possible modifications of these simple systems which may bring about features of observed data are discussed. Some results, in the form of curves of the latency—probability relation, are presented from earlier work and new discrimination experiments. These data are discussed in relation to theoretical interpretations based on a particular stochastic model which describes psychophysical discrimination in terms of the accumulation of units contributing to the overt response.
INVARIANCE OF THE GUTTMAN QUASI‐SIMPLEX LINEAR MODEL UNDER SELECTION
Authors: Mukherjee Bishwa Nath
Published: August 2011

The paper contains a proof that the Guttman additive quasi‐simplex model is invariant under selection of examinees when a set of continuous variables each having different error of measurement is ordered on the simplex continuum in terms of either increasing or decreasing magnitudes of ‘complexity’ provided that selection is based on those measures which are less variable than each of the measures of the remaining set. When variables with highest ‘complexity’ ranks constitute the basis of selection, then such an invariance breaks down. The significance of the problem is discussed in the context of personnel selection. In addition, many implications of the results are stated which hold good for various multivariate statistical techniques.
LINEAR HYPOTHESES IN 2×a FREQUENCY TABLES
Authors: Rodger R. S.
Published: August 2011

An approximate method, with decision‐based error‐rates, for testing linear statistical hypotheses (0κi) about a independent binomial parameters (φj) is given which is more general than the usual methods for partitioning Xm2 from a 2 × a table. Parameters in Table 2 may be used to choose sample‐size (n) for stated alternatives to 0κi and power (or expected proportion of rejections). The procedure may be used for planned tests (v1 = 1) or post‐hoc tests (v1 = a − 1 or v1 = a) and in the latter case the probability of rejecting r of the 0κi (r = 1, 2, …, v1) can be directly calculated for any statement of what is true in the populations.

The results from sampling experiments are used to examine the adequacy of the approximation and compare the method proposed (Rv1) with two others (Gv1 and Zv1) Although the latter methods have a power advantage under some circumstances, their experimental results for n ≤ 30 are generally less close to ‘theory’ than those of Rv1, and they are always arithmetically and conceptually more complex. The results from these experiments suggest that the Rv1 approximation is adequate when n ≥ 10 and the row of smaller expected frequencies (nφ) is greater than or equal to 1. When the φj differ and the true φj approach 0 or 1, “end‐effects” appear but these diminish as n increases.

These methods can be used in a 2×a generalization of the 2 × 2 median test. If this is interpreted not as a test of population medians, but as a test of proportions of population distributions to the right of Me (the value of the common sample median), which is φj in population j, it is distribution‐free.
THE GENETIC ANALYSIS OF CONTINUOUS VARIATION: A COMPARISON OF EXPERIMENTAL DESIGNS APPLICABLE TO HUMAN DATA
Authors: Eaves L. J.
Published: August 2011

The relative efficiencies of various experimental designs are compared for the genetical analysis of human behaviour. Particular attention is paid to the ability of the different designs to separate additive genetic variation from dominance variation. The utility of twins is investigated and it is shown that the relative number of twins need not be large for the statistical efficiency of the experiment to be optimal. The possibility of using foster‐siblings in the place of monozygotic twins reared apart is considered. It is demonstrated that a basic and efficient genetical analysis may be undertaken without recourse to monozygotic twins reared apart. The consequences for efficiency of limited availability of certain groups are investigated, and the method of the study illustrated with the aid of a worked example.
BRIGHTNESS CONTRAST AND THE PERCEPTUAL SCALE
Authors: Treisman Michel
Published: August 2011

A model for brightness contrast is presented which assumes two processes: an initial ‘perceptual’ transformation of visual intensity information, followed by lateral inhibitory interactions which can be represented linearly. The model has been applied to appropriate data and it appears to provide a satisfactory account of both brightness enhancement and brightness depression for homogeneous areas under stable conditions of viewing. This application of the model also provides evidence on the form of the function relating the relevant perceptual correlate of stimulus intensity to the physical values. This appears to be consistent with previous evidence that this relation is a power function with an exponent lying within a range about unity.
A DISTRIBUTION‐FREE TWO‐SAMPLE GOODNESS‐OF‐FIT TEST FOR GENERAL ALTERNATIVES
Authors: Gibbons Jean D.
Published: August 2011

This paper presents a distribution‐free test of the null hypothesis that two independent samples are drawn from identical but completely unspecified populations. The test is a group randomization test, and the test statistic is a function of the sum of squared deviations between group relative frequencies in the samples. As its sampling distribution is conditional only upon the size of the groups formed and not on the individual observed values, the test is completely general and free of population distribution assumptions. It is applicable to categorical, discrete or continuous data, where the alternative does not specify the type of difference between populations. The complete exact null distribution of the test statistic is given for equal‐sized groups and equal sample sizes up to 12 each. The chi‐square approximation is investigated and seems sufficiently accurate for practical use in larger samples. Recommendations are made for the optimal number of groups to use. The merits of this test in comparison with the Kolmogorov‐Smirnov two‐sample maximum deviation test are fully explored.
STOCHASTIC MODELS AND FACTOR ANALYSIS
Authors: Labouvie Erich W.
Published: August 2011

The present paper discusses the relationship between the traditional factor analytic model and stochastic models of test behaviour for the case of dichotomous manifest variables. It is shown that the factor loadings can be interpreted as parameters of item trace lines. Furthermore, by comparing a linear and a nonlinear model of item characteristics, it is suggested that the assumption of a small number of latent dimensions or factors (small in comparison to the number of manifest variables) always requires the estimation of communalities making the explicit conceptualization of specific factors unnecessary. In addition, it is indicated that, because of the arbitrariness of criteria for the number of common factors, the general tendency among researchers to extract a small number of latent dimensions will, for a given data set, lead to quite similar results regardless of the trace line model chosen.
A GENERAL PROCEDURE FOR PARAMETER ESTIMATION FOR THE LAW OF COMPARATIVE JUDGEMENT
Authors: Arbuckle James , Nugent James H.
Published: August 2011

This paper gives a numerical procedure for estimating the parameters of the law of comparative judgement under a variety of conditions. A broad class of goodness‐of‐fit functions is treated, including weighted least‐squares and maximum‐likelihood criteria. Any response function that has the necessary derivatives can be employed. Various kinds of constraints may be imposed on the parameters of the model. Special attention is given to linear constraints; and to equality constraints, where any of the parameters may be assumed to be known in advance and any subset of the parameters may be assumed to take on either a specified or an unspecified common value. In the maximum‐likelihood case, for large samples, approximate standard errors and confidence intervals for the estimated parameters may be obtained, and goodness of fit may be tested by the likelihood‐ratio technique. Numerical examples are provided.
THE EFFECTS OF VARIANCE HETEROGENEITY ON SIMULTANEOUS MULTIPLE‐COMPARISON PROCEDURES WITH EQUAL SAMPLE SIZE
Authors: Howell John F. , Games Paul A.
Published: August 2011

The robustness of three multiple‐comparison procedures (multiple t test, Tukey WSD and Scheffé S test) to the violation of the homogeneous population variance assumption was investigated using three different standard error estimates. These estimates were (1) the square root of two mean square within/n, (2) the standard error of the traditional t test and (3) the standard error of the Behrens‐Fisher t′ statistic. The procedures were highly robust to variance heterogeneity using the Behrens‐Fisher standard error estimate. The procedures were considerably less robust using MSW. The universal use of the Behrens‐Fisher statistic with the Welch solution for critical values is recommended.
SOME HIERARCHICAL SCALING METHODS FOR CONFUSION MATRIX ANALYSIS
Authors: Smith Philip T. , Wilson A. W. , Jones Keith F.
Published: August 2011

It is argued that current scaling models when they are applied to perceptual and mnemonic processes are out of touch with psychological theory. As an alternative, a psychological model is proposed in which stimuli are analysed by a series of feature tests, each feature test being dependent on the results of earlier feature tests in the series and on the other features present in the stimulus. Computer programs are described which fit such models to data, the output of such programs being the best‐fitting hierarchy of feature tests. Detailed analyses are produced for data drawn from studies of speech perception and memory for speech; differences between normal, deaf and aphasic subjects are also discussed. It is claimed that, in comparison with normal scaling methods or with descriptions based simply on raw confusions, this approach offers a more insightful analysis of such data.
A COMPARISON OF THREE PROCEDURES FOR MULTIPLE COMPARISONS AMONG MEANS
Authors: Ury Hans K. , Wiggins Alvin D.
Published: August 2011

For the situation in which the contrasts of interest are limited to the (K/2) comparisons among the means of K samples, Spjøtvoll & Stoline's (1973) extension of Tukey's multiple‐comparison procedure is compared with Scheffé's method (1959) and Dunn's procedure (1961) for significance levels not exceeding 0.05. Rules are given for determining if any method is uniformly preferable (best for all contrasts). Non‐uniform preference rules are also given and applied to some examples. Auxiliary tables are provided for significance levels 0.01 and 0.05 for several values of K and v, the number of degrees of freedom of an independent variance estimate. It is shown that the extended Tukey procedure is uniformly preferable when the sample sizes are equal or ‘nearly’ equal, while Dunn's and, in some cases, Scheffé's method is uniformly preferable when all sample sizes are ‘sufficiently’ different.
An evaluation of some non‐parametric and parametric tests for location equality
Authors: Keselman H. J. , Rogan Joanne C. , Feir‐Walsh Betty J.
Published: August 2011

The Kruskal‐Wallis and normal scores non‐parametric tests of location equality are compared to the parametric analysis of variance F test. In addition to quantifying and manipulating degrees of variance heterogeneity due to combining heterogeneous variances with unequal sample sizes, the tests are compared for their sensitivity, as well as rates of Type I error, under varying conditions of mean variability when sampling from Gaussian and exponential distributions. Even though the asymptotic literature (Pratt, 1964; Puri, 1964) favours the normal scores test, it is found that the Kruskal‐Wallis test is preferable to the normal scores test while the choice between the Kruskal‐Wallis and analysis of variance tests depends upon population shape.
The maximum‐likelihood solution in inter‐battery factor analysis
Authors: Browne M. W.
Published: August 2011

Maximum‐likelihood estimates in closed form are derived for Tucker's (1958) inter‐battery factor analysis model. The estimates of inter‐battery factor loadings may be computed by rescaling correlation coefficients between the original variables and the canonical variables obtained in canonical correlation analysis. It is shown that the likelihood ratio test for the number of inter‐battery factors is identical to Bartlett's (1938) test for the number of non‐zero canonical correlations. An alternative approach analogous to the maximum determinant approach of Howe (1955) and Bargmann (1957) is seen to yield the same solution as that obtained by maximum likelihood. The question of rotation of factors is discussed and an example is given.
Attention bands: Some implications for categorical judgement
Authors: Kornbrot Diana Eugenie
Published: August 2011

It is shown that results of categorical judgement experiments cannot simultaneously conform to a single process signal detectability model and to the recently proposed two process attention band model. Since there is substantial evidence for the Thurstone case V version of the signal detectability model for categorical judgement of prothetic continua, it is argued that the attention band model cannot apply to such judgements. Methods are presented for calculating all the parameters of the attention band model from a single categorical judgement task where the physical stimuli are widely separated.
Preference among preferences as a method for obtaining a higher‐ordered metric scale
Authors: Sahlin Nils‐Eric
Published: August 2011

A method is presented for collecting data which yield a scale on which the entities are ranked in preference and all combinations of value distances are ranked (higher‐ordered metric scale). The method is based on the concept of secondary preference, i.e. preference among preferences. This method is compared with a classical method based on 50–50 game comparison. Two empirical studies are presented. The first examines whether both methods yield the same ordering of value distances. The second involves empirical derivation of a higher‐ordered metric scale.
The asymptotic distribution of elements of a correlation matrix: Theory and application
Authors: Steiger James H. , Hakstian A. Ralph
Published: August 2011

The general asymptotic distribution of elements of a correlation matrix is derived. Applications of the result in robust correlational testing are discussed and illustrated with a numerical example.
A Monte Carlo comparison of small sample procedures for testing the hypothesis that two variables measure the same trait except for errors of measurement
Authors: Rae Gordon
Published: August 2011

A Monte Carlo study was carried out to compare the effectiveness of four different small sample procedures for testing the hypothesis that two variables measure the same trait except for errors of measurement. The results indicated that Forsyth & Feldt's modification of McNemar's test statistic provides the best control of Type I errors when the reliabilities are equal. Kristof's (1973) technique provides a conservative test of the hypothesis but the best control of Type I errors when the reliabilities are not equal. The power values associated with Forsyth ‘& Feldt's statistic were higher than those of Kristof's technique, regardless of test reliability and sample size.
Mechanisms for categorization: Decision criteria and the form of the psychophysical function
Authors: Kornbrot Diana Eugenie
Published: August 2011

The essential features that any satisfactory model of categorical judgement must account for are discussed. The implications of the strong evidence for the Thurstone case V model are drawn out. Then evidence for a linear learning model of criterion setting is presented including new data for isobias functions with either response speed deadlines or physical stimulus difference manipulated. A method for extending linear learning models to encompass joint setting of several criteria is suggested. It is shown that an arcsinh transformation of the Thurstone scale produces a scale which is a linear function of stimulus intensity in decibels. The scale parameter of this transformation remains constant for stimulus ranges greater than 18 dB while changing systematically when sequential presentation is manipulated to improve discrimination.
A measure of categorical clustering based upon a model of recall order
Authors: Robertson Chris
Published: August 2011

A measure of categorical clustering, based upon a model of organization in memory and its effect on recall order, is introduced. The assumptions upon which the model rests are discussed and the way in which the model attempts to describe a recall list is illustrated by an example. Some example recall lists are used to illustrate the behaviour of the model‐based measure of clustering. A BASIC computer program, which can be used to calculate the clustering score, is included in the Appendix.
Latent variable probit ANCOVA: Treatment effects in the California Civil Addict Programme
Authors: Muthén Bengt , Speckart George
Published: August 2011

An ANCOVA model is formulated for two non‐equivalent groups, experimentals and controls. The response variable of interest is a continuous latent variable construct, measured by four dichotomous variables. Estimation and testing draws on methodology of Muthén (1984). The modelling is carried out on data from the California Civil Addict Programme, studying treatment effects related to drug abuse, employment, crime and incarceration.
A randomization procedure for comparing group means on multiple measurements
Authors: Manly Bryan F. J. , McAlevey Lynn , Stevens Denise
Published: August 2011

A randomization procedure is proposed for comparing the means of two or more groups with respect to several variables. The procedure allows the determination of the significance level to apply with testing individual variables such that the probability of declaring any significant differences by chance alone is α. The Bonferroni inequality is sometimes used to obtain the same end. However the Bonferroni inequality gives significance levels that are too stringent with correlated variables.
Distributions of runs of consecutive ascending integers with unequal probabilities
Authors: Hargreaves Colin P.
Published: August 2011

Distributions for the number of consecutive ascending integers in random permutations of the first n integers are described. The case when the probability of a ‘run‐up’ is higher than the probability of ‘no‐run’ is developed and applied to reconstructions of schizophrenic and normal speech.
Contingencies for analysis of contingency tables: More on the chi‐squared test
Authors: Chatterjee Sangit , Delaney Nancy Jo
Published: August 2011

Analysis of the chi‐squared statistic for contingency tables is basic to all branches of science and social science. Rejection of a null hypothesis of no association, especially for large samples, provides little information about the table being studied. Methods, developed by Diaconis & Efron (1985), for interpreting a chi‐squared statistic with regard to its power against a family of alternative distributions arc discussed and illustrated. Higher power is not necessarily implied by higher values for the observed chi‐squared. Power is a function of the computed chi‐squared, the sample size, the row and column marginal totals and the particular alternative hypothesis under consideration. Intermediate models, the relation of one‐way analysis of variance to the random effects model, and the concept of effective sample size are elaborated in the context of actual tables from the literature. Diagnostics for protrusion effects and the topic of granularity are discussed and studied graphically.
Learning in the context of nonlinear psychophysics: The Gamma Zak Embedding
Authors: Gregson Robert A. M.
Published: August 2011

The problem of how a consistent sensory input can be given an invariant name is addressed within the framework of nonlinear psychophysical theory. In order to link sensory transduction processes to cognitive operations an extension of purely psychophysical modelling is used. A hybrid model of sensory switching, produced by injecting a Λ recursion into a non‐Lipschitzian dynamics evolved by Zak, has the capacity to differentiate inputs and encode inputs into classes, in a form that makes vector inputs to neural networks possible. This is a necessary precursor to learning new sensory‐verbal mappings. The distinction between using piecewise linear models and using continuous nonlinear dynamics in theory construction is emphasized.
Bootstrap‐corrected ADF test statistics in covariance structure analysis
Authors: Yung Yiu‐Fai , Bentler Peter M.
Published: August 2011

The asymptotically distribution‐free (ADF) test statistic for covariance structure analysis (CSA) has been reported to perform very poorly in simulation studies, i.e. it leads to inaccurate decisions regarding the adequacy of models of psychological processes. It is shown in the present study that the poor performance of the ADF test statistic is due to inadequate estimation of the weight matrix (W = −l), which is a critical quantity in the ADF theory. Bootstrap procedures based on Hall's bias reduction perspective are proposed to correct the ADF test statistic. It is shown that the bootstrap correction of additive bias on the ADF test statistic yields the desired tail behaviour as the sample size reaches 500 for a 15‐variable‐3‐factor confirmatory factor‐analytic model, even if the distribution of the observed variables is not multivariate normal and the latent factors are dependent. These results help to revive the ADF theory in CSA.
A formal analysis of stressor and stress‐proneness effects on simple information processing
Authors: Neufeld Richard W. J. , McCarty Tracey S.
Published: August 2011

This study examined visual information processing under a stressor of recurring loud sound among groups divided according to psychometrically identified stress susceptibility. Formal models of task performance were employed to address several issues concerning stress effects on cognitive functioning. Examined were effects on parallel versus serial processing structure, task‐wise processing capacity, strategies of allocating processing resources to task components, and curtailment of processing of relevant task elements. Contrary to prediction, stressor presence generated slightly more rather than less evidence of a parallel versus serial processing structure. There was some suggestion of central‐task capacity depletion among more susceptible subjects, in line with certain theoretical positions. Evidence of curtailed exhaustive processing of relevant stimulus items was negative. Most notable was the disruption by stress among susceptible subjects of performance‐enhancing strategies of deploying processing resources across the different task components (elements of the visual display and within‐trial stages of processing). Such effects have received relatively little attention in this research domain; their investigation is shown to be made tractable, however, through the application of selected formal models of information processing.
Spearman and the origin and development of factor analysis
Authors: Bartholomew D. J.
Published: August 2011

Spearman invented factor analysis but his almost exclusive concern with the notion of a general factor prevented him from realizing its full potential. The leadership passed to others, notably Thurstone and Thomson, but progress was hampered by inadequate computing facilities and a limited conceptual framework. It is argued that the fitful progress of factor analyais and its slow and incomplete assimilation into the mainstream of statistical theory can be traced to the lack of a clear idea, until relatively recently, of the role of a model in the development of statistical methods. The combination of an appropriate modelling framework with Spearman's original idea provides a base for further development.
Charles Spearman's contributions to test theory
Authors: Levy Philip
Published: August 2011

This paper examines the origins of test theory in Spearman's early work on the attenuation of correlations due to errors of measurement. His purposes, assumptions, algebraic style and his caveats are featured. Brief attention is given to his early critics. Subsequent developments associated with true score theory and the assessment of reliability are indicated. One or two additional features of Spearman's writings deserve re‐emphasis in a modern context
The expected power of F and t tests conditional on information from an earlier experiment
Authors: Gillett Raphael
Published: August 2011

Simple substitution of an estimate of effect size from an earlier study in the traditional sample size formula is methodologically unsound. A more rigorous method of utilizing information from a previous study when determining sample size is outlined. A computable expression for the expected power of F and t tests conditional upon the result of an earlier experiment is developed. The approach is able to guarantee that experiments in a discipline that seek to achieve a particular level of power will on average attain that desired level, whatever it may be.