▪ I. Lorenz, n.1 Econ.
(ləˈrɛnts)
[The name of Max Otto Lorenz (b. 1876), U.S. statistician, who devised the curve (Q. Publ. Amer. Statistical Assoc. (1905) IX. 217).]
Lorenz curve, a graph in which the proportion of the total personal income of a country is plotted against the proportion of individuals who collectively receive that proportion; more widely, any similar graph relating proportion of a total to the proportion of recipients, etc., of it.
| 1909 Q. Jrnl. Econ. XXIV. 172 A small difference in method of compilation at this point will affect every part of the Lorenz curve. 1920 Econ. Jrnl. XXX. 353 Another interesting measure of inequality is based upon what some writers have called a Lorenz curve. [Note] Originally proposed by Mr. M. O. Lorenz. 1938 M. D. Anderson Dynamic Theory Wealth Distrib. x. 199 A Lorenz curve is a graph depicting the cumulative percentage of total income on one axis and the cumulative percentage of persons receiving the income on the other axis. 1965 McGraw-Hill Dict. Mod. Econ. 306 The greater the sag of the Lorenz curve, the greater the inequality of the income distribution. 1977 D. M. Smith Human Geogr. vi. 135 The Lorenz curve can reveal a number of interesting properties of a distribution. 1980 Sci. Amer. Sept. 76/1 One procedure is to present the observed distribution of household income in a country in a Lorenz curve. 1988 C. Pass et al. Collins Reference Dict. Econ. 85, 50{pcnt} of market sales are accounted for by the largest 25{pcnt} of total firms, as the Lorenz curve indicates. |
▪ II. Lorenz Physics.
(ləˈrɛnts)
Also (erron.) Lorentz.
The name of L. V. Lorenz (1829–91), Danish physicist, used attrib. and in the possessive to designate the ratio k/σT (k = thermal conductivity, σ = electrical conductivity, T = temperature), which has approximately the same value for many metallic elements over a wide range of temperatures.
| 1922 Glazebrook Dict. Appl. Physics I. 459/2 They found that for seven pure metals..the value of Lorenz's constant K/λT was nearly the same over the range 18° to 100°C. 1966 C. R. Tottle Sci. Engin. Materials v. 122 The electron influence on the thermal conductivity of metals is normally far greater than the lattice contribution. When this is the case, the Lorentz constant holds reasonably well. 1966 Phillips & Williams Inorg. Chem. II. xix. 23 On the free-electron theory [of metals] it is predicted that there should be a direct relation between the thermal, k, and electrical, σ, conductivities... The Lorenz number, k/σT, has the theoretical value of 2·45 × 10-8 watt ohm deg-2. |
▪ III. Lorenz, n.3 Physics.
(ˈlɒrɛnts)
[The name of Edward N. Lorenz (b. 1917), U.S. meteorologist.]
Lorenz attractor, a strange attractor in the form of a two-lobed figure resembling a mask, formed by a trajectory spiralling round the mask's ‘eyeholes’ and alternating randomly between its two sides. Cf. strange attractor s.v. *strange a. 17.
| 1976 Lect. Notes Math. DLXV. 147, I shall however turn now to the discussion of an object which has greater geometric simplicity, and intuitive appeal: the Lorentz attractor. 1989 I. Stewart Does God play Dice? vii. 138 (caption) The Lorenz attractor: trajectories cycle, apparently at random, round the two lobes. 1991 Sci. Amer. Aug. 13/2 (Advt.), This 63-minute video turns the Mandelbrot set and Lorenz attractor into visible objects as their discoverers discuss the details of their work. |