4,684 research outputs found
Nonparametric IV estimation of shape-invariant Engel curves
No full textThis paper concerns the identification and estimation of a shape-invariant Engel
curve system with endogenous total expenditure. The shape-invariant specification
involves a common shift parameter for each demographic group in a pooled
system of Engel curves. Our focus is on the identification and estimation of both
the nonparametric shape of the Engel curve and the parametric specification of the
demographic scaling parameters. We present a new identification condition, closely
related to the concept of bounded completeness in statistics. The estimation procedure
applies the sieve minimum distance estimation of conditional moment restrictions
allowing for endogeneity. We establish a new root mean squared convergence
rate for the nonparametric IV regression when the endogenous regressor has unbounded
support. Root-n asymptotic normality and semiparametric efficiency of
the parametric components are also given under a set of ‘low-level’ sufficient conditions.
Monte Carlo simulations shed lights on the choice of smoothing parameters
and demonstrate that the sieve IV estimator performs well. An application is made
to the estimation of Engel curves using the UK Family Expenditure Survey and
shows the importance of adjusting for endogeneity in terms of both the curvature
and demographic parameters of systems of Engel curves
Nonparametric IV estimation of shape-invariant Engel curves
No full textThis paper concerns the identification and estimation of a shape-invariant Engel curve system with endogenous total expenditure. The shape-invariant specification involves a common shift parameter for each demographic group in a pooled system of Engel curves. Our focus is on the identification and estimation of both the nonparametric shape of the Engel curve and the parametric specification of the demographic scaling parameters. We present a new identification condition, closely related to the concept of bounded completeness in statistics. The estimation procedure applies the sieve minimum distance estimation of conditional moment restrictions allowing for endogeneity. We establish a new root mean squared convergence rate for the nonparametric IV regression when the endogenous regressor has unbounded support. Root-n asymptotic normality and semiparametric efficiency of the parametric components are also given under a set of Ѭow-level' sufficient conditions. Monte Carlo simulations shed lights on the choice of smoothing parameters and demonstrate that the sieve IV estimator performs well. An application is made to the estimation of Engel curves using the UK Family Expenditure Survey and shows the importance of adjusting for endogeneity in terms of both the curvature and demographic parameters of systems of Engel curves.
Voice Compression and Communications: Principles and Applications for Fixes and Wireless Channels
No full textUp-to-date, expert coverage of topics in wireless voice communications Voice communication is the most important facet of mobile radio service. Even when the predicted surge of wireless data and Internet services becomes a reality, voice will remain the most natural means of human communication. Voice Compression and Communications details issues in wireless voice communications and treats compression, channel coding, and wireless transmission as a joint subject. Part I covers background material, whereas Part II provides detailed information on both proprietary and standardized analysis-by-synthesis codecs, including the speech codecs of virtually all existing wireline-based and wireless systems. Parts III and IV discuss mainly research-based wideband, audio, as well as very low-rate schemes likely to find their way into future standards. Voice Compression and Communications describes fundamental concepts in a non-mathematical way early in the book for those with only a background knowledge of signal processing and communications. More advanced readers will find detailed discussions of theoretical principles, future concepts, and solutions to various specific wireless voice communications problems
Speaking of trade: Its effect on agriculture
No full textThis archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu.Dorow, Norbert; Engel, N.E.; Guither, Harold D.; Hadley, Herbert D.; Hildreth, R.J.; Houch, J.P.; Jones, Bob F.; Robinson, B.H.; Rose, Gordon; Woods, Fred; Wyckoff, J.B.. (1978). Speaking of trade: Its effect on agriculture. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/203917
1973-10-25 Morehead State Concert and Lecture Series J.P. Donleavy
No full textRenowned author J.P. Donleavy speaks on the plight of an author and the methods to write, recorded on October 25, 1973
Melitoma danunciae Oliveira & Engel 2015
No full text<i>Melitoma danunciae</i> Oliveira & Engel, 2015 <p> <b>(Figs. 1 E-G and 5)</b></p> <p> <b>Material examined</b> (1♀, 2♂♂): 1♀, Argentina, Formosa, afueras de Formosa Capital, 07/I/2019, S/ <i>Ipomoea carnea,</i> Col. L. Alvarez, A. Avalos & J.P. Torretta. 1♂, Argentina, Corrientes, San Miguel, pan trap (-27.9932, -57.5816), 03/I/2022, Col. M. Aguirre. 1♂, Argentina, Corrientes, San Miguel, Koe Mimbi, pan trap azul (-27.9928, -57.5808), 03/I/2022, Col. M. Aguirre.</p> <p> <b>Distribution:</b> Brazil: Bahia (Oliveira & Engel, 2015). Argentina: Corrientes and Formosa. <b>New records.</b></p> <p> <b>Remarks:</b> <i>Melitoma danunciae</i> is included in the <i>segmentaria</i> species group and was generally misidentified as <i>Melitoma segmentaria</i> (Fabricius, 1804), from which it can be easily differentiated by the white pubescence of the head (Fig. 1E), the female basitibial plate rounded apically (Fig. 1F), and male S7, S8 and genitalia (Oliveira & Engel, 2015).</p>Published as part of <i>Alvarez, Leopoldo Jesús, Ramello, Pablo José, Avalos, Adan Alberto, Almada, Valentín, Aguirre, Marina Soledad, Torretta, Juan Pablo & Lucia, Mariano, 2024, Contributions to the wild bee fauna in Argentina (Hymenoptera: Anthophila), pp. 1-13 in Papéis Avulsos de Zoologia 64</i> on page 4, DOI: 10.11606/1807-0205/2024.64.006, <a href="http://zenodo.org/record/10943066">http://zenodo.org/record/10943066</a>
Entrainment and detrainment rates from the piv measurements at the top of laboratory analogs of stratocumulus and cumulus clouds
No full textWe analyze mixing at the top of laboratory analogs of convective clouds: stratocumulus and cumulus to investigate entrainment of environmental air into the cloud. We retrieve two components of air velocity using Particle Image Velocimetry technique. Suitable image processing allows to determine cloud–clear air interface. Using velocity differences between cloudy and clear sides of the interface we calculate entrainment / detrainment rates
Vortex Dynamics in The Transitional and Turbulent Wake of 6:1 Prolate Spheroid at 45-deg incidence angle
No full textThe incompressible flow past a 6:1 prolate spheroid with an inclination angle of 45o at Re = 3,000 has been studied by means of direct numerical simulations (DNS). The Reynolds number is based on the inflow velocity and minor-axis length. The preliminary results presented here are focused mainly on vortex dynamics and vortical structures in the wake. The wake behind this configuration starts almost symmetric but is soon strongly deflected and bent as it evolves to the intermediate wake. A pair of unequal-strength vortices dominates the intermediate wake, of which one exhibits the shape of a long vortex tube while the other rapidly breaks down into turbulent-like vortical structures
Experimental characterisation of large scale structures in a high Reynolds number turbulent boundary layer
No full textA very large field of view (4δ x 1δ) with a good spatial resolution owing to the use of four 2k x 2k pixel cameras was conducted in a flat plate boundary layer at two Reynolds numbers (Reθ ≈7,500 and 20,000). Comparing the flow statistics with previously obtained hot-wire data under similar flow conditions show good agreement. The goal of this experiment is to detect and characterise the large scale motions which develop in the log region of a high Reynolds number turbulent boundary layer
Letter from J.P. Bradley to Mr. [William] S. Martin The Dominguez Estate Company, June 28, 1940
No full textRegarding attached payment by Mr. K.L. Schaap settling his account
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