The effect of characteristics of the data distribution on subjective probability judgments.

Accuracy in making probability judgments about the characteristics of data distributions was examined in this study. In particular, the effects of four characteristics on probability estimation: problem type, variability of the data distribution, amount of information, and anchor point were investigated. Previous research has examined the impact of single factors on single measures of subjective probability (usually the mean), but has not studied the interaction of factors or used more than one dependent measure. A questionnaire containing two problem scenarios was given to 747 introductory psychology students. One scenario dealt with the amount of rainfall in cm. per year in Buenos Aires, Argentina, and the other scenario was concerned with the average number of points scored per game in one season by a pro basketball team. Both problem scenarios were fictitious but appeared genuine to the subjects. A list of numbers representing data from preceding years followed each problem scenario. Each list was derived from computer generated random normal distributions and had either low or high variability, five or 25 years of data, and a last data point of 90, 100, or 110 units. Subjects were asked to generate a three category subjective probability distribution for the present year for each scenario. They also indicated their level of confidence in these probability judgments on a six point scale. Subjects also made point estimates of the mean from memory for each scenario. Four dependent measures resulted: the mean and standard deviation of the subjective probability distribution, the confidence judgment, and the point estimate of the mean from memory. The major findings of the study were: (1) The mean of the subjective probability distribution was affected by the interaction of anchor point and amount of information. The mean estimate was biased in the direction of the anchor point in the low amount of information condition but not in the high amount of information condition. (2) The standard deviation of the subjective probability distribution was affected by problem variability. Standard deviations were larger for the high variability condition than for the low variability condition. Also, females\u27 judgments were more variable than males\u27 judgments. (3) Confidence judgments were lower for the high variability condition than for the low variability condition. Confidence judgments were also affected by gender and by a gender by problem type interaction. Overall, males were more confident about their judgments than females. Further, males were more confident about the basketball problem than about the rainfall problem while females were equally confident about both problems.Dept. of Psychology. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1990 .K545. Source: Dissertation Abstracts International, Volume: 52-11, Section: B, page: 6114. Thesis (Ph.D.)--University of Windsor (Canada), 1989

Measurement of mesoscopic High-TcT_c superconductors using Si mechanical micro-oscillators

In a superconducting mesoscopic sample, with dimensions comparable to the London penetration depth, some properties are qualitatively different to those found in the bulk material. These properties include magnetization, vortex dynamics and ordering of the vortex lattice. In order to detect the small signals produced by this kind of samples, new instruments designed for the microscale are needed. In this work we use micromechanical oscillators to study the magnetic properties of a Bi$_2$Sr$_2$CaCu$_2$O$_{8 + \delta}$ disk with a diameter of 13.5 microns and a thickness of 2.5 microns. The discussion of our results is based on the existence and contribution of inter and intra layer currents.Comment: 4 pages, 6 figure

Analysis of the effectiveness of industrial R and D

The criteria used by private industry in evaluating and selecting proposed research and development projects for implementation, and also in determining which R and D facilities are to be acquired were investigated. Conceptual and practical issues inherent in any quantitative analysis of the contribution of R and D to economic growth were identified in order to assist NASA in developing approaches for analzying the economic implication of its own R and D efforts

Nonlinear Micromechanical Casimir Oscillator

The Casimir force between uncharged metallic surfaces originates from quantum mechanical zero point fluctuations of the electromagnetic field. We demonstrate that this quantum electrodynamical effect has a profound influence on the oscillatory behavior of microstructures when surfaces are in close proximity (<= 100 nm). Frequency shifts, hysteretic behavior and bistability caused by the Casimir force are observed in the frequency response of a periodically driven micromachined torsional oscillator.Comment: 4 pages, 4 figures; added and rearranged references; added comments on sensitivit

Theory of Neutron Diffraction from the Vortex Lattice in UPt3

Neutron scattering experiments have recently been performed in the superconducting state of UPt3 to determine the structure of the vortex lattice. The data show anomalous field dependence of the aspect ratio of the unit cell in the B phase. There is apparently also a change in the effective coherence length on the transition from the B to the C phases. Such observations are not consistent with conventional superconductvity. A theory of these results is constructed based on a picture of two-component superconductivity for UPt3. In this way, these unusual observations can be understood. There is a possible discrepancy between theory and experiment in the detailed field dependence of the aspect ratio.Comment: 11 pages; uses REVTEX, APS and PRABIB styles; 2 Postscript figure files include

The effects of probability level and sample size on subjective probability distributions.

Dept. of Psychology. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1984 .K546. Source: Masters Abstracts International, Volume: 40-07, page: . Thesis (M.A.)--University of Windsor (Canada), 1984

Mechanism of thermally activated c-axis dissipation in layered High-Tc_c superconductors at high fields

We propose a simple model which explains experimental behavior of $c$-axis resistivity in layered High-T$_c$ superconductors at high fields in a limited temperature range. It is generally accepted that the in-plane dissipation at low temperatures is caused by small concentration of mobile pancake vortices whose diffusive motion is thermally activated. We demonstrate that in such situation a finite conductivity appears also in $c$-direction due to the phase slips between the planes caused by the mobile pancakes. The model gives universal relation between the components of conductivity which is in good agreement with experimental data.Comment: RevTeX, 4 pages, 2 Postscript figure

Characterization of Titanium Films Deposited with a Cathodic Arc Using a Straight Magnetic Duct

Nanostructured Ti films were obtained employing a cathodic arc with a straightmagnetic filter. The films were characterized using X-ray diffraction, scanning electron andatomic force microscopy. The films were found to be dense and with columnar grains,whose size increased with the exposure time. The number of macroparticles, the filmroughness and the deposition rate were also analyzed, and the latter compared with theresults of a fluid plasma model. Number of macroparticles and film roughness in sampleslocated ahead of the magnetic duct inlet were higher than those determined fromsamples placed inside the magnetic duct. The deposition rate depended on the axial andradial position inside the duct. The thickness along the radial position was more uniformfor samples located at axial positions near the filter extremes, but the mean depositionrate was lower at these positions. Measured and modeled deposition rates agreed reasonablywell.Fil: Bermeo, Diego Fernando. Universidad Santiago de Cali; ColombiaFil: Della Torre, H.. Universidad del Valle de Mexico; MéxicoFil: Kleiman, Ariel Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Minotti, Fernando Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; ArgentinaFil: Marquez, Adriana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física del Plasma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física del Plasma; Argentin

Purification of a phospholipase C froM Bacillus cereus

Phospholipase C activity present in the growth medium of Bacillus cereus was purified 20-fold by chromatography on polyethyleneimine-cellulose columns, or by treatment with protamine sulfate and subsequent chromatography on DEAE-cellulose columns. Purified enzyme preparations retained the ability to hydrolyze ethanolamine phosphoglycerides in the absence of choline phosphoglycerides. A typical preparation had a specific activity of about 9 [mu]moles/min per mg toward purified diacyl glycerophosphoryl ethanolamine and a specific activity of about 15-20 [mu]moles/ min per mg toward diacyl glycerophosphorylmonomethylethanolamine and diacyl glycerophosphoryl choline. Monoacyl glycerophosphate was not hydrolyzed under similar conditions.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32856/1/0000232.pd