Language, Employment and Earnings in the United States: Spanish-English Differentials from 1970 to 1990

This paper analyzes employment and earnings differentials between Spanish speakers and English speakers in the United States, using data from the 1970, 1980, and 1990 U.S. censuses. The results show that Spanish speakers, both men and women, do not perform as well in the labor market as English speakers. The results also reveal that Spanish-English earnings and unemployment differentials increased slightly in the 1970s, most likely because of rapid growth in the number of Spanish speakers. By contrast, these differentials increased sharply in the 1980s, also a period of rapidly increasing supply. However, there is no evidence that the widening of differentials in the 1980s reflects an increase in the labor market rewards to English language proficiency. Rather, they appear to be the result of Spanish speakers having relatively little of those labor market characteristics, most notably education, whose market value increased dramatically during the 1980s.

Models of Firm Behavior Under Minimum Wage Legislation

This paper sets out three simple models of firm behavior under minimum wage legislation. The key feature of these models is that they account for important aspects of the government's mechanism for monitoring and enforcing compliance with the minimum wage law. The major results of the paper are (1) that minimum wage legislation does not generally lead to upward movements along labor demand curves but rather, that it often leads to movements off, and to the left, of the labor demand curve; (2) that minimum wage legislation is likely to have a positive effect on the distribution of wages paid to workers who would earn less than the minimum in the absence of the legislation, but is not likely to bring all of those workers up to the minimum; and (3) that imposing additional penalties on second offenders promotes compliance by firms with no previous violations. The paper considers the implications of these results for empirical work on the adverse employment effects of minimum wage legislation andfor the design of government compliance mechanisms.

The Changing Labor Market Position of Canadian Immigrants

This paper uses pooled 1971, 1981, and 1986 Canadian census data to evaluate the extent to which (1) the earnings of Canadian immigrants at the time of immigration fall short of the earnings of comparable Canadian-born individuals, and (2) immigrants' earnings grow more rapidly over time than those of the Canadian-born. Variations in the labor market assimilation of immigrants according to their gender and country of origin are also analyzed. The results suggest that recent immigrant cohorts have had more difficulty being assimilated into the Canadian labor market than earlier ones, an apparent consequence of recent changes in Canadian immigration policy, labor market discrimination against visible minorities, and the prolonged recession of the early 1980s.

Rotational velocities of A-type stars II. Measurement of vsini in the northern hemisphere

This work is the second part of the set of measurements of vsini for A-type stars, begun by Royer et al. (2002). Spectra of 249 B8 to F2-type stars brighter than V=7 have been collected at Observatoire de Haute-Provence (OHP). Fourier transforms of several line profiles in the range 4200--4600 A are used to derive vsini from the frequency of the first zero. Statistical analysis of the sample indicates that measurement error mainly depends on vsini and this relative error of the rotational velocity is found to be about 5% on average. The systematic shift with respect to standard values from Slettebak et al. (1975), previously found in the first paper, is here confirmed. Comparisons with data from the literature agree with our findings: vsini values from Slettebak et al. are underestimated and the relation between both scales follows a linear law: vsini(new) = 1.03 vsini(old) + 7.7. Finally, these data are combined with those from the previous paper (Royer et al. 2002), together with the catalogue of Abt & Morrell (1995). The resulting sample includes some 2150 stars with homogenized rotational velocities.Comment: 16 pages, includes 13 figures, accepted in A&

Cooperative ordering of gapped and gapless spin networks in Cu2_2Fe2_2Ge4_4O13_{13}

The unusual magnetic properties of a novel low-dimensional quantum ferrimagnet Cu$_2$Fe$_2$Ge$_4$O$_{13}$ are studied using bulk methods, neutron diffraction and inelastic neutron scattering. It is shown that this material can be described in terms of two low-dimensional quantum spin subsystems, one gapped and the other gapless, characterized by two distinct energy scales. Long-range magnetic ordering observed at low temperatures is a cooperative phenomenon caused by weak coupling of these two spin networks.Comment: 4 pages, 4 figure

Field-induced magnetic behavior in quasi-one-dimensional Ising-like antiferromagnet BaCo2V2O8: A single-crystal neutron diffraction study

BaCo2V2O8 is a nice example of a quasi-one-dimensional quantum spin system that can be described in terms of Tomonaga-Luttinger liquid physics. This is explored in the present study where the magnetic field-temperature phase diagram is thoroughly established up to 12 T using single-crystal neutron diffraction. The transition from the N\'eel phase to the incommensurate longitudinal spin density wave (LSDW) phase through a first-order transition, as well as the critical exponents associated with the paramagnetic to ordered phase transitions, and the magnetic order both in the N\'eel and in the LSDW phase are determined, thus providing a stringent test for the theory.Comment: 17 pages with 15 figure

Language, Employment, and Earnings in the United States: Spanish-English Differentials from 1970 to 1990

This paper analyzes employment and earnings differentials between Spanish speakers and English speakers in the United States, using data from the 1970, 1980, and 1990 U.S censuses. The results show that Spanish speakers, both men and women, do not perform as well in the labor market as English speakers. The results also reveal that Spanish-English earnings and unemployment differentials increased slightly in the 1970s, most likely because of rapid growth in the number of Spanish speakers. By contrast, these differentials increased sharply in the 1980s, also a period of rapidly increasing supply. However, there is no evidence that the widening of differentials in the 1980s reflects an increase in the labor market rewards to English language proficiency. Rather, they appear to be the result of Spanish speakers having relatively little of those labor market characteristics, most notably education, whose market value increased dramatically during the 1980s

Real time decoherence of Landau and Levitov quasi-particles in quantum Hall edge channels

Quantum Hall edge channels at integer filling factor provide a unique test-bench to understand decoherence and relaxation of single electronic excitations in a ballistic quantum conductor. In this Letter, we obtain a full visualization of the decoherence scenario of energy (Landau) and time (Levitov) resolved single electron excitations at filling factor $\nu=2$. We show that the Landau excitation exhibits a fast relaxation followed by spin-charge separation whereas the Levitov excitation only experiences spin-charge separation. We finally suggest to use Hong-Ou-Mandel type experiments to probe specific signatures of these different scenarios.Comment: 14 pages, 8 figure