【導(dǎo)讀】sunprecedented. hypertension.1990,andreached43%in2021(NBS,2021;WorldBank2021).Bythemiddleofthis. infectiousdiseases,inlow-ineaswellashigh-inecountries(Riley,2021),

　　

【正文】 uals living in munities that at some time experience a defined degree of urbanization and those that do not. The time varying group dummies, get x, equal one if the individual is exposed to a defined degree of urbanization at time t. Since we restrict the sample to those in the bottom part of the distribution of the urbanicity index at the beginning of the panel, these dummies are zero for all individuals at their first observation. The estimate of the average treatment effect of urbanization on the probability of experiencing fair or poor health is given by the marginal effect of these dummies. Further, we control for individual covariates it z (see Table 4) and a full set of both munity and province dummies big Although timeinvariant differences between treatment and control munities are taken into account, this DID estimator does not exploit the panel nature of the data and so is potentially rendered inconsistent by any individual level unobserved heterogeneity that is correlated with any of the righthandside variables in (1). We deal with this by applying the conditional legit estimator to a model like (1), but including a fixed unobservable individual level effect and, consequently, no time invariant repressors. This es at the cost of smaller sample size, as the fixed effects legit model only uses those observations for which there is variation in the dependent variable. With a third estimator, we exploit more of the information in the ordinal SAH variable by taking the approach of FerreriCarbonell and Fritters (2021), who have shown that an ordered logit model with fixed effects can be estimated as a fixed effects logit model, where the ordered data are collapsed to binary data and the model allows individualspecific This involves creating a binary health indicator ( worse health ) that equals one if the individual reports worse health at time t than the average he/she reports across all waves and then using this as the dependent variable in a fixed effects variant of (1) estimated by conditional logit (B246。ckerman and Ilmakunnas, 2021). In the remainder of the paper, we will refer to this as the fixed effects ordinal logit. Using Verbeek and Nijman?s (1992) test, we found some evidence of attrition bias in the simple logit However, once fixed effects are taken into account。 attrition can only induce inconsistency when selection is related to the idiosyncratic errors. We tested this by adding the lagged selection indicator to the fixed effects logit model and the fixed effects ordered logit model (estimated on the total panel), and doi ng a ttest for the significance of the selection indicator (Jones et al, 2021).13 The null of no effect was not rejected in both models (pvalue= and respectively), indicating that our fixed effects estimators are not biased by attrition, providing further reason for focusing on them. Throughout, standard errors are corrected for clustering at the individual (and so any higher) level. the proposal about taking an urbanization path with Chinese characteristics, speeding up our country?s urbanization and carrying out the urbanization strategy, which was put forward in the report to the 16th National Congress of Communist Party of China, has a very significant practical meaning and profound historic meaning in building a well off society in all round way and realizing the modernization. Moreover, this article discusses the connotation and the ways about urbanization path with Chinese characteristics. Urbanization and Productivity A general equilibrium model with increasing return to labor specialization and economies of transaction agglomeration is developed to address the residential landrent escalation associated with the urbanization process, which is in turn endogenized as a result of the evolution of the division of labor. The interplay among the geographical pattern of transactions, trading efficiency and the work size of the division of labor plays a crucial role in our story of urbanization. We show that: as transaction conditions are improved, the equilibrium level of division of labor and individuals? specialization levels increase。 the urban landrent increases absolutely as well as relative to that in the rural area, the relative per capita lot size of residence in the urban and rural areas decreases。 the diversity of occupations in the urban area and the population share of urban residents increase。 and the productivity of all goods and per capital real ine increase. The purpose of the paper is to explain several important phenomena of urbanization, including the urban landrent escalation, decreases in the relative per capita consumption of land in the urban and rural area, increases in the population size of the urban area pared to the rural area, and the absolute increase of diversity of occupations in the urban area as well as relative to that in the rural area, as different aspects of evolution in the division of labor. The intimate relationship between cities and the division of labor has indeed long been recognized by Xenopnon (Gordon 1975), William Petty (1682), Alfred Marshall (1890, ), Mills (1972), Scott (1988) and others. However, as noted by Stigler (1976, pp. 12091210), there was no formal theory of the division of labor and specialization in the mainstream economics: “The last of Smith?s regrettable failures is one for which he is overwhelmingly famous – the division of labor…… . (A)lost no one used or now uses the theory of division of labor, for the excellent reason that there is scarcely such a theory. … Smith gave the division of labor an immensely convincing presentation – it seems to me as persuasive a case for the power of specialization today as it appeared to Smith. Yet there is no evidence, so far as I know, of any serious advance in the theory of the subject s