19,876 research outputs found
Comparing shapes of engel curves
No full textWe measure how different the shapes of Engel curves are across 59 commodity groups. The same analysis is carried out for their derivatives and variances. While Engel curves possess a relatively homogeneous shape, significantly more heterogeneity is present in derivatives and when particular sub-classes of income are considered.Consumption, Kernel smoothing, Rank correlation, Curve shape
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
DEMAND SYSTEM CHOICE BASED ON TESTING THE ENGEL CURVE SPECIFICATION
No full textIt is common to use a demand systems approach in estimating the key parameters from household consumption data. In conducting these studies the researcher is faced with selecting a functional form. In turn, each functional form implies a particular shape for the Engel curves. This analysis highlights the importance of testing the shape of Engel curves, especially if the researcher is interested in elasticity estimates well away from the sample mean. Using consumption data for selected households in Italy it is shown that many popular functional forms are rejected by the data.Demand and Price Analysis,
Quadratic engel curves and consumer demand
No full textThis paper presents a model of consumer demand that is consistent with the observed expenditure patterns of individual consumers in a long time series of expenditure surveys and is also able to provide a detailed welfare analysis of shifts in relative prices. A nonparametric analysis of consumer expenditure patterns suggests that Engel curves require quadratic terms in the logarithm of expenditure. While popular models of demand such as the Translog or the Almost Ideal Demand Systems do allow flexible price responses within a theoretically coherent structure, they have expenditure share Engel curves that are linear in the logarithm of total expenditure. We derive the complete class of integrable quadratic logarithmic expenditure share systems. A specification from this class is estimated on a large pooled data set of U.K. households. Models that fail to account for Engel curvature are found ro generate important distortions in the patterns of welfare losses associated with a tax increase
Millicent Engel to Esther\r\nLovejoy
No full textLetter to Esther Lovejoy from Millicent Engel, regarding her work in Haiti
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.
An Engel Curve Analysis of Household Expenditure in Taiwan: 1996-98
No full textSeven systems of Engel curves for expenditures on ten commodity groups were estimated using Taiwanese household expenditure data for the period from 1996 through 1998. Results show that the estimated expenditure elasticities are insensitive to the choice of functional forms.Engel curve, Taiwan, Consumer/Household Economics,
Some curiosites about the Engel method to estimate equivalence scales
No full textThis paper lends legitimacy to the food share as an indicator of welfare by demonstrating the conditions necessary in empirical work for the Engel method of estimating equivalence scales to provide an exact measure of welfare. In analogy to a money metric of utility, the Engel's food share is shown to be a “quantity metric of utility.”Engel method
Hyptiogastritinae Engel 2006
No full textKey to Genera of Hyptiogastritinae <p>1.Forewing with discal cell below level of M+Cu (i.e., 1Rs+M forming node with 1Rs, M+Cu, and 1Cu, and with 1M absent) (Fig. 4A); integument with areas of yellow maculation; moderate-sized wasps, approximately 4.5–5 mm in length [Archeofoenini, new tribe].. 2</p> <p> —Forewing with discal cell above level of M+Cu (i.e., 1M present, with 1Rs+M arising from “basal vein” and 1Cu in line with M+Cu); integument dark brown to black, without areas of maculation; small wasps, less than 4 mm in length [tribe Hyptiogastritini Engel]............................................................. <i>Hyptiogastrites</i> Cockerell</p> <p> 2.Compound eye large; mandible bidentate; forewing membrane uniformly clear; forewing 2Rs+M and 2Rs weakly angled, 2Rs subequal to 2Rs+M, r-rs equal to 2Rs, and 2M+Cu entirely absent; gena dark brown to black; metafemur dark brown except yellow at apex; metatibia yellow except at extreme apex and on majority of inner surface dark brown.............................................................. <i>Archeofoenus</i>, n. gen.</p> <p> —Compound eye small; mandible simple; forewing membrane infumate in apical half; forewing 2Rs+M and 2Rs distinctly angled, 2Rs shorter than 2Rs+M, r-rs longer than 2Rs, and minute 2M+Cu present (i.e., 1Rs slightly basad 1 Cua as figured by Cockerell, 1917b); gena entirely yellow; metafemur yellow except black at base; metatibia yellow except black at apex....................................................... <i>Protofoenus</i> Cockerell</p>Published as part of <i>Engel, Michael S., 2017, New Evanioid Wasps from the Cenomanian of Myanmar (Hymenoptera: Othniodellithidae, Aulacidae), with a Summary of Family-Group Names among Evanioidea, pp. 1-28 in American Museum Novitates 2017 (3871)</i> on page 11, DOI: 10.1206/3871.1, <a href="http://zenodo.org/record/5368793">http://zenodo.org/record/5368793</a>
Exotic Holomorphic Engel Structures on C4
No full textA holomorphic Engel structure determines a flag of distributions (Formula presented.). We construct examples of Engel structures on (Formula presented.) such that each of these distributions is hyperbolic in the sense that it has no tangent copies of (Formula presented.). We also construct two infinite families of pairwise non-isomorphic Engel structures on (Formula presented.) by controlling the curves (Formula presented.) tangent to (Formula presented.). The first is characterised by the topology of the set of points in (Formula presented.) admitting (Formula presented.)-lines and the second by a finer geometric property of this set. A consequence of the second construction is the existence of uncountably many non-isomorphic holomorphic Engel structures on (Formula presented.)
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