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Likelihood Ratio as Weight of Forensic Evidence:�A Closer Look
No full textThe forensic science community has increasingly sought quantitative methods for conveying the weight of evidence. Experts from many forensic laboratories summarize their findings in terms of a likelihood ratio. Several proponents of this approach have argued that Bayesian reasoning proves it to be normative. We find this likelihood ratio paradigm to be unsupported by arguments of Bayesian decision theory, which applies only to personal decision making and not to the transfer of information from an expert to a separate decision maker. We further argue that decision theory does not exempt the presentation of a likelihood ratio from uncertainty characterization, which is required to assess the fitness for purpose of any transferred quantity. We propose the concept of a lattice of assumptions leading to an uncertainty pyramid as a framework for assessing the uncertainty in an evaluation of a likelihood ratio. We demonstrate the use of these concepts with illustrative examples regarding the refractive index of glass and automated comparison scores for fingerprints
A close-up of a yellowish marble from Coimbra, Portugal, part of the NIST stone wall
No full textThis is an image of fine-grained yellowish marble from Coimbra, Portugal. The stone is part of the NIST stone wall, which was built using 2,352 stones from 47 US states and 320 from 16 foreign countries. The wall is approximately 12 m long, 4 m high, 0.6 m thick at the bottom, and 0.3 m at the top. The aim of the wall construction was to study the aging process of stones used in construction under outside weathering conditions
Close-up of a stone sample set in the NIST stone wall
No full textThe NIST stone wall was built using 2,352 stones from 47 US states and 320 from 16 foreign countries. The wall is approximately 12 m long, 4 m high, 0.6 m thick at the bottom, and 0.3 m at the top. The aim of the wall construction was to study the aging process of stones used in construction under outside weathering conditions
Oscar G. Lange
No full textOSCAR G. LANGE
NBS/NIST: 1902-1937
INDUCTED: 2017
Birth: 1867, Cassel, Germany
Death: July 1956, Rockville, Maryland
EDUCATION:
Germany - apprenticeship trained mechanician
CITATION:
For designing and constructing unique scientific instruments and supervising technicians that all were critical to the conduct of scientific research in the early days of the National Bureau of Standards.
POSITIONS HELD AT NBS/NIST:
Mechanician, 1902-1904
Chief NBS Instrument Shops, 1904-1937
SIGNIFICANCE OF WORK:
NBS Director Samuel W. Stratton hired Mr. Lange in 1902, one of the first 22 people hired at NBS, to serve as a mechanician to design and build the many instruments needed for America’s standards and technical activities that were not available commercially. As Stratton observed, “One not familiar with the method of carrying on scientific research scarcely appreciates the extent to which the services of skilled artisans are utilized.” When an instrument shop was established in 1904, Stratton assigned Lange to head it and to establish close relations between himself and the scientific staff.
HONORS:
Not available.
MEMBERSHIPS:
Not available.
PUBLICATIONS/PRODUCTS:
Priest, I. and Lange, O., built the Priest-Lange Reflectometer (1920) to accurately measure optical reflectance of
materials; used until 1971.
Lange, O., constructed the first iron-clad Thomson galvanometer (1914) to measure the radiant energy of stars
(Audio) Oral history interview of David R. Lide, September 19, 2017 / with William (Bill) Gadzuk, Frank Lovas, Ced Powell, Bill Kirchhoff, John Rumble
No full textOral history interview of David R. Lide, September 19, 2017 / with William (Bill) Gadzuk, Frank Lovas, Ced Powell, Bill Kirchhoff, John Rumble
No full textSoftware for Complete Mode Structure Analysis of a Light Field
No full textWe present a software package aimed at simulating photon-number probability distributions of a range of naturally occurring classical and non-classical states of light. This software can generate arbitrary probability distributions based on the known mode structure of a light field. It also can solve the reverse problem, i.e. reconstructing the mode structure of a light field based on a given probability distribution. The mode structure fully describes a light field and contains the information about the source of light without a direct access to the source. The multimode fields simulated by this software include those comprised of a number of thermal modes and an optional Poisson mode. In addition, conjugated multimode sources (such as those created via parametric downconversion (PDC) or four-wave mixing (FWM)) can be simulated. Using this software, and with a minimal set of assumptions, we demonstrate a nearly- perfect reconstruction of multimode fields comprised of several correlated modes corresponding to squeezed vacuum states and several uncorrelated thermal and Poisson modes corresponding to background light.(software
Gertrude Blanch
No full textGERTRUDE BLANCH
NBS/NIST: 1938-1954
INDUCTED: 2017
Birth: 2 February 1897, Kolno, Poland
Death: 1 January 1996, San Diego, California
EDUCATION:
New York University, BS (Mathematics), 1932
Cornell University, PhD (Mathematics), 1935
CITATION:
For excellence as Technical Director of the Mathematical Tables Project and for pioneering contributions to the field of numerical analysis for early computers.
POSITIONS HELD AT NBS/NIST:
Unit Supervisor, Mathematical Tables Project 1938-1943
Technical Director, Mathematical Tables Project, 1943-1948
Assistant Director for Computing, Institute for Numerical Analysis, National Applied Mathematics Laboratories,
1948-1954
HONORS:
Fellow, American Association for the Advancement of Science (1962) (strongly influenced by NBS work) Federal Woman’s Award from President Lyndon Johnson (1964) (strongly influenced by NBS work)
MEMBERSHIPS:
Association for Computing Machinery (Founding member)
American Mathematical Society
Mathematical Tables Project performed work for Army Corps of Engineers, the Navy Bureau of Ordnance, and
the National Defense Research Committee
PUBLICATIONS:
More than 40 publications including:
Blanch, G., Lowan, A.N, Marshak, R E., and Bethe, H.A., "The Internal Temperature Density Distribution of the
Sun," J. Astrophysics, 37-45 (1942)
Blanch, G., "On the Computation of Mathieu Functions," J. Mathematical Physics, vol. 25, 1-20 (1946) Blanch, G., "Numerical Solution of Parabolic Partial Differential Equations,” J. Research of the National Bureau of Standards, vol. 50, no. 6, 343-356 (1953)
Blanch G. and Rhodes, I., "Tables of Characteristic Values of Mathieu’s Equation for Large Scale Values of the
Parameter J," J. Washington Academy of Science, vol. 45, no. 6, 166-196 (1955)
Blanch, G., "Mathieu Functions," Handbook of Mathematical Functions with Formulas, Graphs and Mathematical Tables (M. Abramowitz and I. Stegun, eds.), National Bureau of Standards, Applied Mathematics Series No. 55 (1964