本书界定了居民收入差距适度性的内涵，提出了居民收入差距适度性的判断标准，揭示了居民收入差距及其适度性的主要影响因素，从居民收入差距、经济增长、资源配置效率、社会稳定与公平几大方面构建了居民收入差距适度性评价指标体系，提出了居民收入差距适度性的测度方法，从预测、预警、调控三个方面构建了居民收入差距适度性预警机制。在此基础上，对中国居民收入差距进行统计测度与分解，对中国居民收入差距及其适度性的主要影响因素进行实证检验，对中国居民收入差距适度性进行综合评价，对中国居民收入差距适度性相关问题进行问卷调查，对国外调节居民收入差距的国际经验与教训进行横向比较分析，从明确警情、寻找警源、分析警兆和预报警度几大环节对中国居民收入差距适度性进行监测预警分析。通过理论研究与实证分析，得出了具有启发意义的研究结论。从初次分配领域制度机制设计、再分配领域公共政策选择等方面提出缩小居民收入差距的政策建议，为政府制定科学合理的收入分配政策提供参考依据。

Currently，in the theoretical field，the definition of residents’income gap moderation is not reasonable because of many subjective factors，the judgments are based more on empirical criteria and lack of theoretical basis，the methods of measurement are not practical and have not formed a scientific and reasonable comprehensive evaluation index system，the influencing factors are often lack of empirical testing and interpreted by only a few factors，researches on early warning of residents’income gap moderation are almost empty，and early warning mechanisms have not been established.Therefore，it has a very important theoretical meaning.In intensifying the theory study on residents’income gap moderation and building a relatively complete theoretical framework.By studying the definition，standards and evaluation system of residents’income gap moderation，this book can help to make more accurate judgments and objective evaluation，to investigate the degree of adaptation and coordination on income gap of residents，economic growth，the efficiency of resource allocation，and the social stability.Through the research on the influencing factors of residents’income gap moderation，this book contribntes to reveal the nature of residents’income gap moderation in China，and proposes some targeted policy recommendations.The research on the influencing warning mechanism of residents’income gap moderation contributes to early warning to take control to take.Therefore，the empirical analysis of residents’income gap moderation has important reference value and significance for government departments to formulate scientific and reasonable policies to regulate residents’income gap effectively.In the aspect of theoretical research，this book clearly defines the implications of residents’income gap moderation，puts forward the criteria，reveals the main influencing factors，and builds the evaluation index system from the aspects of income gap，economic growth，efficiency of resource allocation，social stability and equity.This book also puts forward the method to measure residents’income gap moderation and constructs a relatively complete theoretical framework from building early warning mechanism through three aspects of forecasting，early warning and regulating.Empirically，this book measures and decomposes the residents’income gap moderation in China，analyzes the main factors of residents’income gap moderation，makes a comprehensive evaluation，conducts a questionnaire survey of related problems about residents’income gap moderation，and compares the international experiences and learns from the lessons of foreign regulation.This book monitors residents’income gap moderation from clearing alarm，finding source，analyzing signs and warning degree.Furthermore，it puts forward the policy recommendations of narrowing the income gap and provides the important referable basis for government to formulate a scientific and reasonable income distribution policy from the mechanism design of primary distribution system and the public policy choice of redistribution.The book is organized into twelve chapters.The first chapter is an introduction.In this chapter，the first step is to set forth the background and significance of the research.And the Uterature review.Then this chapter puts forward the contents，research objectives，methodologies and technology roadmap.Lastly，this chapter points out the key scientific issues to be resolved，the characteristics，innovations and insufficiencies of the whole book.The second chapter is the theoretical basis of residents’income gap moderation.Firstly，this chapter defines the basic concepts of income，income distribution，income gap.Secondly,this chapter elaborates some measuring indexes of the income gap like Gini coefficient，Theil index，coefficient of variation.Thirdly，this chapter defines the connotation of residents’income gap moderation，describes the basic features of income gap，and puts forward the standards from three aspects:whether income gap promotes sustained economic growth，whether it is conducive to promote the efficiency of resource allocation，and whether it is conducive to the promotion of social stability and equity.The third chapter is to study the evaluation system of residents’income gap moderation.Firstly，it elaborates the basic principles of building a modest income gap evaluation index system.Secondly，it constructs evaluation index system from income gap，economic growth，efficiency of resource allocation，social stability and equity.Thirdly，this chapter describes the measurements of the coordination of economic systems.Fourthly，it proposes the measurements of income gap，i.e., comprehensive and classified evaluation indexes of income gap.The fourth chapter is the statistical measurement and decomposing analysis of the income gap among Chinese residents.Based on 6937 questionnaires’data from 31 provinces，this chapter conducts a statistical measure and analyses the income gap among urban residents，the income gap among rural residents，the income gap among industries and the income gap between urban and rural residents.And it draws the corresponding conclusions according to the Gini coefficient，Theil index，coefficient of variation with the decomposing formulas.The fifth chapter is the analysis of the influencing factors and the contributing rate of income gap.Based on both macro and micro perspective，this chapter reveals the main influencing factors of the income gaps among urban residents，rural residents，urban-rural and regional residents.Secondly，this chapter conducts an empirical analysis on the main factors and contributing rate on the income gaps and draws the corresponding conclusions by using macro statistics and micro survey data.The sixth chapter makes comprehensive evaluation and analysis of residents’income gap moderation.Firstly，it uses factor analysis and PCA（principal components analysis） method to measure income gap evaluation index，economic growth evaluation index，resource allocation efficiency index，social stability and equity evaluation index and comprehensive evaluation index of the coordinated development of social economy by using macroeconomic statistical data.Secondly，this chapter calculates the comprehensive evaluation index and classified evaluation index of static and dynamic moderation on income gaps.This chapter also makes a reasonable comprehensive evaluation of the status about residents’income gap moderation and draws the corresponding conclusions by inspecting the coordination degree of income gap，economic growth，efficiency of resource allocation and social stability and equity.The seventh chapter is the survey analysis of residents’income gap moderation in China.Based on 6937 copies of residents questionnaire survey data from 31 provinces，this chapter investigates with questionnaire and draws the conclusions which have the inspiring significance about the hot issues with public concern，like the basic judgment on the present residents’income gap moderation，the main reasons for the income gap expansion，public tolerance of income distribution，public satisfaction rate of income gap，the possible consequences of the increasing income distribution inquity，the apparent effects of the inquity to rural residents compared with urban residents，the most important distributive justice，the relationship between equity and efficiency at this stage，the main factors affecting social stability，the currently main risk of inefficiency and the policies to promote fair distribution.The eighth chapter analyzes the multiple choices model of residents’income gap moderation in China.Based on 6937 copies of residents questionnaire survey data from 31 provinces，this chapter constructs multi Probit model and makes an empirical test from the main influencing factors from the micro perspective on the income gap suitability of rural residents，urban residents，and urban-rural residents.Finally，this chapter draws the corresponding conclusions and provides references for the government to formulate a scientific and reasonable income distribution policy.The ninth chapter is the study of the early warning mechanism of residents’income gap moderation.Firstly，this chapter elaborates the theories and methods of economic early warning.Secondly，it determines early warning alarm indicators with a single index.This book chooses a comprehensive evaluation index of static residents’income gap moderation and classified evaluation indexes as the warning indexes of residents’income gap moderation.It also establishes the ARIMA model to predict the alarm value of warning indexes and uses an comprehensive early warning methods to construct an early warning mechanism of residents’income gap moderation from four aspects:confirming warning conditions，finding warning sources，analyzing warning signs，forecasting warning degrees.The tenth chapter is the monitoring and early warning analysis of residents’income gap moderation.Firstly，by using the evaluation indexes which have been mentioned in chapter six，this chapter uses single index monitoring and early warning for analysis based on the early warning process of single index.Secondly，according to the comprehensive index of the early warning process，this chapter makes a comprehensive monitoring and early warning analysis of residents’income gap moderation in China and draws the corresponding conclusions from the analysis of warning conditions，warning sources，warning signs，warning indexes，warning limits and warning degrees.The eleventh chapter is the international experience and enlightenment of regulating income gap.This chapter focuses on the analysis of the experience and enlightenment from narrowing the income gap in the BRIC countries，Japan and Germany.This foreign experience of regulating residents’income gap has a very important significance for references to effectively narrow the income gap in China and to formulate scientific policies and measures.The twelfth chapter is the conclusions，suggestions and prospects.Firstly，this chapter summarizes the conclusions of the whole book from eleven aspects.Secondly，it puts forward the policy recommendations of narrowing the income gap from twelve aspects mechanism design of the initial distribution system，public policy of the redistribution.Finally，it carries on the forecast to the future direction of the research from five aspects.Throughout the paper，we get the following conclusions:（1） From the micro analysis of the questionnaire results，the income gap in China is reletively large，the Gini coefficient is more than 0.4 over the warning line，and the internal gap is far more than the gap between the groups.There are big differences among income gaps of residents because of the basic characteristics of the individual and the family，the human capital，political capital,physical capital，geographical environment，and the regional system.（2）From the results of the macro statistical data analysis，the income gap among residents in China presents an expanding trend,economic growth continues and the allocating efficiency of resources increases，social stability and equity degree rise in volatility，the overall economic and social development operate well.Furthermore from the suitability evaluation indexes，each system such as economic growth，the efficiency of resources allocation，social stability and fairness is moderate.（3）From the macro level，the aspects such as economic growth，physical capital，human capital，open foreign policy，the urbanization level，financial development，government policy have significant effects on income gap.Among them，the contribution rate of residents’ income gap on economic growth，physical capital，human capital，open foreign policy on is relatively small.From the micro level，the basic personal and family characteristics，human capital，political capital，regional differences have significant effects on residents’ income and the income gap.Human capital，regional differences have larger contribution rates on residents’ income gap,while,the basic personal and family characteristics and political capital have relatively small cintribution rates.（4）From the survey results，residents’ income gap at present stage exceeds the reasonable limit.“power-trading，rent-seeking and corruption” are the main reasons of the widening of the residents’ income gap.Residents’ income inequality tolerance is strong，but most of the residents are not satisfied with current income distribution.“The raise in social instability degree” is the major consequence caused by unfair income distribution phenomenon.“Official corruption” and “ excessive gap between the rich and the poor” are the most important factors and risks of social stability and economic efficiency.“The government should deal with the relationship between efficiency and eguity in the primary distribution and redistribution，and pay more attention to fairness in redistribution.”“Ban illegal incomes，punish corruption” are the most important measures to promote fair distribution and narrow the income gaps.（5）From the questionnaire statistical results，compared with urban residents，“education”，“social security”，“public infrastructure” are the major unfair manifestations to rural residents.“Financial development differences between urban and rural areas”，“public infrastructure and the differences in social security”，“urban and rural dual structure” and “urban and rural differences in human capital” are the main factors affecting the income gap between urban and rural areas.“Improving the state of dual structure between urban and rural areas，promoting the development of urban and rural areas ”，“vigorously developing education，improving the quality of the whole rural labor force”，“developing rural small and medium-sized financial institutions，expanding rural policy financing channels” and “building a balanced urban and rural social security system” are the effective ways to narrow the income gap between urban and rural areas.“The lack of employment skills in rural labor”，“the lack of agricultural technology and capital” and “low price of agricultural and sideline products ” are the main reasons of the difficulties in increasing the income of farmers.Furthermore，“promoting agricultural technology，developing modern agriculture”，“increasing the training for employment skills of rural labor force” and “breaking the barriers between urban and rural areas，establishing a unified，open labor market” and “increasing the purchase price of agricultural products” are the main ways to realize the peasants’ income.（6）From the results of analysis of questionnaire and probit model，household income per capital，human capital，political capital have significant positive influences on the suitability of residents’income gap.The political capital，geographical environment，farmers income per capita are the core factors affecting the suitability of the rural residents’income gap.Urban residents income per capita，educational level，job title，occupation，institutional factor，industry difference，registered permanent residence are the important factors affecting the suitability of the urban residents’income gap.Income per capita，educational level，urban and rural differences are the key factors that influence the suitability of the urban and rural residents’income gap.（7）From the results of the single early warning indicators and the results of the comprehensive early warning index，residents’income gap moderation in China is basically in a non-alarm state.Keywords:income gap；moderation；evaluation system；influencing factors;questionnaire；multiple choice model；early warning.