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The Competitive Saving Motive Evidence From Rising Sex Ratios and Savings Rates in China

The Competitive Saving Motive Evidence From Rising Sex Ratios and Savings Rates in China
The Competitive Saving Motive Evidence From Rising Sex Ratios and Savings Rates in China

NBER WORKING PAPER SERIES

THE COMPETITIVE SAVING MOTIVE:

EVIDENCE FROM RISING SEX RATIOS AND SAVINGS RATES IN CHINA

Shang-Jin Wei

Xiaobo Zhang

Working Paper 15093

https://www.doczj.com/doc/7f17601188.html,/papers/w15093

NATIONAL BUREAU OF ECONOMIC RESEARCH

1050 Massachusetts Avenue

Cambridge, MA 02138

June 2009

The authors would like to thank Marcos Chamon, Avi Ebernstein, Lena Edlund, Roger Gordon, Ed Hopkins, Tatiana Kornienko, Justin Lin, Olivier Jeanne, Simon Johnson, Nancy Qian, Junsheng Zhang,and seminar participants at the NBER and various universities for helpful discussions, and John Klopfer,Lisa Moorman and Jin Yang for able research assistance. The views expressed herein are those of the author(s) and do not necessarily reflect the views of the National Bureau of Economic Research.

? 2009 by Shang-Jin Wei and Xiaobo Zhang. All rights reserved. Short sections of text, not to exceed two paragraphs, may be quoted without explicit permission provided that full credit, including ? notice, is given to the source.

The Competitive Saving Motive: Evidence from Rising Sex Ratios and Savings Rates in China Shang-Jin Wei and Xiaobo Zhang

NBER Working Paper No. 15093

June 2009

JEL No. D1,F3

ABSTRACT

While the high savings rate in China has global impact, existing explanations are incomplete. This paper proposes a competitive saving motive as a new explanation: as the country experiences a rising sex ratio imbalance, the increased competition in the marriage market has induced the Chinese, especially parents with a son, to postpone consumption in favor of wealth accumulation. The pressure on savings spills over to other households through higher costs of house purchases. Both cross-regional and household-level evidence supports this hypothesis. This factor can potentially account for about half of the actual increase in the household savings rate during 1990-2007.

Shang-Jin Wei

Graduate School of Business

Columbia University

Uris Hall 619

3022 Broadway

New York, NY 10027-6902

and NBER

shangjin.wei@https://www.doczj.com/doc/7f17601188.html,

Xiaobo Zhang

International Food Policy Research Institute

2033 K Street, NW

Washington, DC 20006

x.zhang@https://www.doczj.com/doc/7f17601188.html,

”… [A] surge in growth in China and a large number of other emerging market economies … led to an excess of global intended savings relative to intended capital investment. That ex ante excess of savings propelled global long-term interest rates progressively lower between early 2000 and 2005.That decline in long-term interest rates across a wide spectrum of countries statistically explains, and is the most likely major cause of, real-estate capitalization rates that declined and converged across the globe, resulting in the global housing price bubble.” Alan Greenspan, Wall Street Journal, March 11, 2009

1. Introduction

High savings rates in certain countries are said to be a major contributor to the recent housing price bubbles and the global financial crisis by depressing global long-term interest rate in the last decade (Greenspan, 2009). The Chinese national savings rate, at about 50 percent of GDP in 2007, has caught special attention. This savings rate is high in at least three senses. First, it is higher than most other countries, including East Asian countries that are already known to have high savings rates. Second, it is higher than in China’s own past: the gross domestic savings rate as a share of GDP rose by about 15 percentage points since 1990. Finally, it is higher than China’s already-high investment-to-GDP ratio. China’s household savings are approximately half of its national savings. (In 2007, the household savings as a share of the household disposal income was 30%).

The purpose of this paper is to test a new hypothesis regarding household savings behavior using Chinese regional and household data. Before doing that, let us review existing explanations in the literature. The first is the life cycle theory (Modigliani, 1970, and Modigliani and Cao, 2004), which predicts that the savings rate rises with the share of working age population in the total population. This explanation doesn’t appear to be consistent with profile of savings at household level (Chamon and Prasad, 2008). The second explanation has to do with a precautionary savings motive in combination with a rise in income uncertainty, which is favored by Blanchard and Giavazzi (2005) and Chamon and Prasad (2008). The problem is that while both pension systems and the public provision of health care in China have been improved since 2003, household savings as a share of disposable income rose sharply during the same period. This time series pattern contradicts the precautionary motive theory. The third explanation is a low level of financial development. This has the same difficulty as the last explanation since the financial system is most likely more efficient today than a few years ago yet the

savings rate still rose. The fourth explanation is cultural norms. But cultural norms tend to be persistent, and therefore are unlikely capable of explaining the visible rise in the savings rate over the last two decades1.

In this paper, we suggest that an alternative competitive saving motive may be at work: families with sons compete with each other to raise their savings rate in response to ever rising pressure in the marriage market. Competitive saving by these families spills over to greater savings by other families, possibly through raising the prices of non-tradable goods such as housing. The increased pressure in the marriage market comes from China’s rising sex ratio imbalance, which has made it progressively more difficult for men to get married. As far as we know, we are the first in the literature to propose this hypothesis as an explanation for a rising savings rate in China. Toward the end of the paper, we argue that the explanation is likely applicable to many other countries as well.

We provide a series of evidence. First, across provinces, we show that the local savings rate tends to be higher in regions and years in which the local sex ratio (for the pre-marital age cohort) is higher. This continues to be true after we control for local income, social safety net, the age profile of the local population, and province and year fixed effects.

Second, in recognition of possible endogeneity of and measurement error in local sex ratios, we employ instrumental variables where the local sex ratio for the pre-marital age cohort is shown to be linked to local financial penalties for violating family planning policies set more than a decade earlier (as Ebenstein, 2008, and Edlund et al, 2008, also document). With two-stage least squares estimation, the effect of local sex ratios on local savings rates remain positive and statistically significant. In fact, the point estimate

1 We do not study corporate savings behavior in this paper. The Chinese corporate savings rate has risen sharply in recent years, accounting now for about half of the national savings rate (Kuijs, 2006). The corporate savings behavior is a separate puzzle to be explained. The existing explanation suggests that a combination of state-ownership and windfalls in resource sectors is the primary driver. (The government savings rate is relatively moderate and has turned negative in 2008-09.) We note, however, that a recent paper by Bayoumi, Tong and Wei (2009) discusses China’s corporate savings rate in a global context and casts doubt on the usual interpretation. Because corporate savings rates have been rising globally (Bates, Kahle, and Stulz, 2005; and IMF, 2005), it turns out that the Chinese corporate savings rate is only modestly higher than those of other countries (by

2 percentage above the global average savings rate when comparing listed companies across countries). So differences in corporate savings are unlikely to be a big part of the cross country differences in national savings rates. Moreover, comparing corporate savings by Chinese firms of different ownership, in resource and non-resource sectors, Bayoumi, Tong and Wei (2009) do not find evidence that state-owned firms save more than private firms, or that the corporate savings rate is unusually high in resource sectors. This casts doubt on the notion that a high Chinese corporate savings rate is mainly a result of poor corporate governance and inefficiencies tied either to state-ownership or to windfalls in resource sectors.

becomes larger. This suggests that an increasing imbalance in the sex ratio causes a rise in the savings rate.

Third, we examine household data using household surveys that cover 122 rural counties and 70 cities. While households with a son typically save more than households with a daughter, we do not regard this per se as supportive evidence of our hypothesis, since other channels could account for this difference. Instead, the evidence that we find compelling is that savings by otherwise identical households with a son tend to be greater in regions with a higher local sex ratio. This is something clearly predicted by our hypothesis, but not by any other existing explanations. In addition, we find that savings by households with a daughter do not decline in regions with a high sex ratio, which is consistent with our interpretation that the savings pressure on households with a son spills over to other types of households. We discuss reasons that these patterns at the household level are unlikely to be the outcome of some selection in the data.

Finally, we provide several supplementary pieces of evidence. We show that local housing values indeed tend to be higher in regions with a higher local sex ratio, even after taking into account local income. This is direct evidence that the competitive pressure on households with a son in the marriage market may trigger other households to save more just to cope with higher local housing costs. We also provide some evidence that household level savings rates tend to be linked to a wedding event in a family in a quantitatively significant way, and that a groom’s family tends to save more than a bride’s family in preparation for the wedding.

We do not wish to claim that no combination of the existing explanations could contribute to a higher savings rate. Instead, we suggest a competitive saving motive as an additional explanation. The estimated effect of a rising sex ratio on the Chinese savings rate is economically significant, and can be projected to become even more important in the foreseeable future. Based on the point estimate (0.74) in the IV regression, a rise in the sex ratio for the pre-marital age cohort from 1.05 to 1.14 (which is actual increase in Chinese sex ratio for the age cohort of 7-21 from 1990-2007) would lead to a rise in the savings rate by 6.7 percentage points, which is 48% of the actual increase in the household savings rate. If we run separate regressions for rural and urban areas, we find that the elasticity of the local savings rate with respect to the local sex ratio is larger in

rural areas than in urban areas. The increase in the rural sex ratio is estimated to account about 53% of the actual increase in the rural savings rate from 1990 to 2007.

Because the sex ratio imbalance at birth has been increasing steadily since mid-1980s, the imbalance for the pre-marital age cohort will almost surely be higher over the next decade than in the last decade, even if the sex ratio at birth starts to be reserved soon. This implies that the incremental savings rate that is stimulated by the competitive savings motive will almost surely rise in importance in the near future.

A high savings rate in a large economy is a significant contributor to global current account imbalances. Once one recognizes that the sex ratio imbalance is a structural factor behind a rising savings rate, it should be clear that a discussion of global imbalances that focuses narrowly on exchange rates or even social safety nets is incomplete. Furthermore, policy actions that improve the economic status of women could potentially reduce the sex ratio imbalance by reducing parental preference for sons (Qian, 2008). A change in the family planning policy that relaxes birth quotas could also reduce the imbalance. Because of their important implications for aggregate savings and current account imbalances, these changes deserve more attention that they receive now.

The paper is organized in the following way. In Section 2, we develop the argument more fully, lay out some caveats and possible answers to them, and make connections to related literatures. In Section 3, we provide statistical evidence for our hypothesis. Finally, in Section 4, we conclude and discuss possible future research. A data appendix explains the sources and definitions of the main variables, including measures of sex ratio imbalance and of savings rates.

2. Developing the argument: unbalanced sex ratios and competitive savings

In this section, we first document the evolution of the sex ratio imbalance in the Chinese society over the last three decades. We then explain why this could trigger a race to raise savings rate, and connect this discussion to related literature.

From unbalanced sex ratios to “bare branches”

Left to the nature, the sex ratio at birth (in a society without massive starvation) is generally around 106 boys per 100 girls (with human biology compensating for a slightly

higher mortality rate for infant boys than girls). The sex ratio was balanced or slightly below normal in the 1960s and 1970s (mostly likely due to malnutrition). The sex ratio at birth in China was close to be normal in 1980 (with 106 boys per 100 girls), but climbed steadily since the mid-1980s to over 120 boys for each 100 girls in 2005 (Li, 2007; Zhu, Lu, and Hesketh, 2009) and estimated to be 124 boys/100 girls in 2007. By 2005, men outnumbered women at age 25 or below by about 30 million. The excess men cannot be married mathematically. The number of unmarried men -sometimes referred to as “bare branches” in colloquial Chinese - continues to rise as the sex ratio imbalance deteriorates2.

Some men may partner off as gays, and others may emigrate or marry women from other countries. Because the scale of the “bare branches” is so large – 30 million men are more than the entire male population of Italy or of many other countries, and because most “bare branches” come from low income households, actions by a small portion of men do not provide a practical solution to the problem. In any case, a rising sex ratio imbalance must imply a diminishing probability that a man will find a bride3.

From fear of becoming a “bare branch” to competitive savings

Most men have a desire to get married. It may be safer to say that, in an Asian society, parents of a son strongly prefer for their son to be married. As the competition

for a dwindling pool of potential wives intensifies, the parents of a son (or a son himself) will try harder to improve the son’s prospects for marriage. Postponing consumption and raising the household savings rate is one such action that families may take. To be successful, a family needs to save more than enough number of other competing families. If all families think the same way, this leads to competitive saving. (Of course, in general

2 If some new-born girls are not reported by their parents with hopes to be pregnant again with a son, then the sex ratio imbalance at birth could be overstated in official statistics. To assess the quantitative importance of this possibility, we compare the sex ratio at birth in the 1990 population census with the sex ratio for the 10 years old in the 2000 census. It is reasonable to assume that parents would not hide their 10-year old girls from census-takers in 2000. First, those parents who would like to try for another child in 1990 most likely would have done so already within ten years, and have paid a fine for violating family planning policy by 2000. In addition, there were also positive incentives to report the girls who have reached school age since registration was required for (free) immunization shots and school attendance. Since the sex ratios for both the new-borns in 1990 and the 10 years old children in 2000 were 1.12, we conclude that the under-reported infant girls, as a proportion of total number of new-born girls, are not large enough to make a noticeable distortion to reported sex ratio imbalance. Zhu. Li and Hesketh (2009) reached the same conclusion with a somewhat different methodology.

3 A fraud has recently emerged in which some women pretend to be willing to marry bachelors in a rural area in return for a bride price (“cai li”) on the order of RMB 40,000 (about US$5900, or “five years’ worth of farm income”). The women would then run away after the wedding with the bride price (“It’s cold cash, not cold feet, motivating runaway brides in China,” by Mei Fong, Wall Street Journal, June 5, 2009)

equilibrium, the total number of unmarried men will not be changed by household savings decision. But an individual family’s desire to improve marriage prospects for its son may lead all families with a son to compete to increase their savings.]

The idea that accumulating more wealth may improve one’s chance in the marriage market is not unique to China. For example, pop star Madonna has declared in the hit song, “Material Girl,” that: “We are living in a material world/ and I am a material girl/Some boys try and some boys lie but/ I don’t let them play/ Only boys who save their pennies/ make my rainy day.” So she sees a connection between a man’s savings rate and his success in dating. To be clear, our hypothesis does not require women to be material girls (in China or elsewhere). Indeed, other factors can be important for success in finding a spouse. But other things being equal, as long as more wealth improves a man’s likelihood for marriage, parents with a son (or a son himself) will be encouraged to raise their savings rates. Many factors (such as health and appearance) are difficult to control, but the savings rate is one such thing that parents or men themselves can act on. However, we are not saying that the savings behavior is the only variable that is altered by a rising sex ratio. Instead, parents with a son may do all things in their power to improve their son’s marriage prospect, including perhaps investing more in their son’s education, and pushing him to work harder. The hypothesis in the current paper is that postponing parents’ consumption and raising their savings rate may be one such variable that responds positively to a rising sex ratio.

For the sex ratio to affect household savings rates, parents don’t have to know local sex ratio statistics. There is an invisible hand at work. Consider two otherwise identical households with a son, one in a region with a high sex ratio, and the other in a region with a low sex ratio. Parents in the first region would observe or be told by relatives or colleagues with a son that it is very expensive for their sons to find a girlfriend and to marry. The expectation for how much the parents (or the sons) need to contribute to their son’s new household, given costs of housing, cars, furniture, or honeymoons, would differ in the two regions. The types of furniture, cars and honeymoons, and local housing prices may already reflect the degree of competition in a local marriage market, and thus affect the savings required of parents with a son. In other

words, even without knowledge of local sex ratio statistics, parents with a son may make savings decisions that reflect the local sex ratio.

The initial inspiration for the hypothesis comes (from our visits to the National Zoo in Washington DC, and) from the literature on evolutionary biology. In nature, male sea lions or walruses tend to be physically larger than corresponding females; in fact, this pattern holds for most species. A leading hypothesis for why this occurs, sexual dimorphism, conjectures that because bigger and stronger males have an advantage in competing for and retaining females, differences in size are reinforced over time by natural selection (Weckerly 1998). It is likely that humans had to do the same a long time ago; that is why men, on average, are somewhat taller and larger than women. By now, the (sexual) returns to progressively larger males are much lower, if not negative. Men may discover that possessing a larger house, a bigger savings account, and more general wealth is a more effective mating strategy.

Existing literature, potential caveats, and counter-arguments

No other paper in the existing empirical literature that we are aware of makes a connection between sex ratios and savings rates. Nonetheless, a relevant economics literature is the work on status goods, positional goods, and social norms (e.g., Cole, Mailath and Postlewaite, 1992; Hopkins and Kornienko, 2004 and 2009). When allowing certain goods to offer utility beyond their direct consumption value (i.e., through “status,” which in turn could affect the prospect of finding a marriage partner), it is easy to show that consumption and savings behavior can be altered. It is important to point out, however, that the effect of a rising sex ratio imbalance on savings rates is conceptually ambiguous. In particular, when competition in the marriage market increases, men (or their parents) may compete by increasing their conspicuous consumption, if conspicuous consumption effectively signals their attractiveness; this would result in a decline in the savings rate. Our response is that, while conspicuous consumption may increase the frequency of dating, the probability of securing a marriage partner may depend more on showing substantial wealth than on showing off a few flashy goods. Furthermore, a visible way to demonstrate a man’s desirability is by owning a larger house (at least in a developing country like China), which requires a larger savings before the purchase is

made than otherwise. Both signaling strategies can induce households with a son to raise their savings rate. In any case, it is an empirical question as to whether savings rates are positively or negatively related to sex ratio imbalances.

The theoretical models in Hopkins (2009) and Hopkins and Kornienko (2009) could be interpreted to predict that a rise in sex ratio imbalances leads to a rise in savings rates. In a possible reading of their models, men compete for potential wives through effort (including by raising their savings rate). Assume that the reward for a higher savings rate is a better chance to win a wife. Men with the lowest savings rates, on the other hand, may not find a wife. As the fraction of men who may stay unmarried increases, men (without coordination) compete by saving more. The resulting level of savings for men is inefficiently high: if all men were to cut their savings by the same amount, the chance for each of them to be matched with a wife would stay the same, but they would have avoided postponing consumption unnecessarily.

When the savings effect dominates the conspicuous consumption effect for parents with a son (or unmarried men), would parents with a girl (or unmarried women) save less since a rising sex ratio is a favorable development for them? Indeed, could the reduction in their savings be so much as to completely offset the increase in savings by parents with a son or unmarried men? In a way, we can wait for the data to tell us the answer. Here, it is useful to point out the existence of an opposing force that could potentially raise the savings rate even by parents with a daughter. That force is the price of housing. Parents with a son (or unmarried men) may attempt to increase their competitiveness by buying a larger house, and may bid up housing prices in a region with an unbalanced sex ratio. As a consequence, even parents with a daughter have to save more in order to afford housing. This is a spillover effect4.

This discussion has clear implications for the empirical work. First, we need to estimate the net effect of higher local sex ratios on local savings rates. Second, it would be useful to check how savings by households with a son or with a daughter respond to local sex ratios. Third, it would be informative to check if local housing prices are indeed linked to local sex ratios (holding constant other factors).

4h When all men save more, the reward for savings by women or parents with a daughter increases, if wealthier men also prefer relatively wealthy women. As a result, parents with a daughter are also more willing to save. For a theoretical model that may deliver this result, see Peters and Siow, 2002. This could be an additional spillover channel.

Determinants of sex ratio imbalance

Sex ratio imbalance comes almost entirely from sex selective abortions. This, in turn, results from a combination of three factors: (a) parental preference for sons; (b) some limit to the number of children a couple is allowed or wants to have, which for the Chinese is a strict family planning policy; and (c) availability of inexpensive technology to screen the sex of a fetus (Ultrasound B in particular) and to perform abortions.

Our empirical work will start with regressions that assume exogenous sex ratios. This assumption can be justified by recognizing that parental preference for sons is part of a culture, and as such, it changes only very slowly. Korea has experienced a sustained increase in its sex ratio imbalance for about 25 to 30 years, which has only recently started to decline; this evidence is consistent with our assumption (Guilmoto, 2007).

We nonetheless also report instrumental variable regressions that allow for potential endogeneity of (and measurement error in) sex ratios. The instrumental variables for sex ratio in the pre-marital age cohort explore regional variations in the financial penalty for violating birth quotas, set by regional governments years before newborns grow to marriageable age.

3. Statistical Evidence

Since 1980, both the sex ratio for marriage-age youths and the savings rate in China have been rising. In Figure 1, we present a time series plot of standardized versions of both variables,5 with the sex ratio at birth lagged by twenty years. The sex ratio is lagged since the median age of first marriage for Chinese women is about 20. The two standardized variables, visually, are highly correlated (the actual correlation coefficient is 0.822). While this is highly suggestive, it is not a rigorous proof by itself.

Panel regressions across Chinese provinces during 1980-2007

We start by examining provincial-level data for any association between local savings rates and local sex ratios. We perform a panel fixed effects regression that links a

5 standardized variable = (raw variable – mean)/standard deviation.

location j’s savings rate in year t with the sex ratio for the appropriate age cohort in that same location and year, controlling for location fixed effects, year fixed effects, and other factors. To be precise, our specification is the following:

Savings_rate j,t = β Sex_ratio j,t +X j, tΓj,t + province fixed effects + year dummies +e j,t

Following Chamon and Prasad (2008), we define the local savings rate by log (income net of taxes / living expenditure).6 This definition is less susceptible to extreme values, and makes the error term more likely to satisfy the normality assumption. We cluster the standard errors by province.

Ideally, we would like to know sex ratios for a fixed age cohort in every region and in every year. However, such data are not available as the Chinese population census is carried out only once every few years (in 1982, 1990 and 2000). Moreover, only the 2000 census offers public data for individual age groups at the provincial level. Given these constraints, we make the following short cut: we focus on the sex ratios for the age cohort 7-21 in all years, inferred from the 2000 population census. For the age cohort 7-21 in 2007, we infer their sex ratio from the age cohort 0-19 in the 2000 census, since the two groups should theoretically be the same. Similarly, for the age cohort 7-21 in 1990, we infer their statistics from the cohort 17-31 in the 2000 census; and so on.

A caveat with this method is that the actual sex ratio is likely to be different from the inferred one for all years other than 2000. In particular, because the mortality rates for boys and young men are generally slightly higher than those for girls and young women, we may under-estimate the true sex ratios for years before 2000 and over-estimate them for years after 2000. However, under the assumption that measurement errors are common across all regions in any given year (but may vary from year to year), we can eliminate the effect of measurement errors by including year fixed effects in regressions.

As control variables, we include both log income and proportions of the local population in the age brackets of 0-19 and 20-59, respectively. Table 1a presents the summary statistics of the major variables used in the provincial level analysis. Table 1b

6 Income and expenditure data, which are aggregated based on nationwide rural and urban household surveys, are from various issues of China Statistical Yearbooks.

lists the outlier provinces – those with the highest and lowest sex ratios in various years. For example, in 2005, Jiangxi and Shaanxi had the highest sex ratios at birth, both in excess of 130 boys per 100 girls. At the other end of the spectrum, Tibet, Liaoning, Jilin, and Xinjiang had the lowest sex ratios at birth, with 109 boys or less per 100 girls.

In Column 1 of Table 2, we report regression results with only sex ratio, income and population shares for two age groups as the regressors (plus province and year fixed effects). The effect of local income on local savings rates is positive: a one percent increase in local income is associated with local savings rate 0.26 percentage points higher. The coefficient of local sex ratio (for the age cohort 7-21) is 0.39 and statistically different from zero at the 5% level. In other words, the local savings rates tend to be higher in regions with a more imbalanced sex ratio.

The age profile of local populations produces some puzzling patterns. In contrast to the prediction of the life cycle hypothesis, the share of working age population (the age cohort of 20-59) has a negative coefficient. This means that old-age households and households with children save more than do households in between. We note that this is consistent with the notion that parents save more when they have children, and that old people save more either because they have a strong bequest motive, or because they realize their financial need in the old age is greater. Regardless of these explanations, we note that similar patterns are documented in Chamon and Prasad (2008).

The existing literature has hypothesized that rising income and job uncertainty is what motivates the Chinese to save more. In Column 2, we use the proportion of local labor force that work for state-owned firms or government agencies as a proxy of the degree of job security. Under the precautionary savings hypothesis, the savings rate should decline with better job security. The coefficient indeed has a negative coefficient (-0.14); however, it is not statistically significant. In any case, the coefficient on sex ratio is still positive and significant. The point estimate (0.70) is now substantially larger.

Because men and women may both have different savings rates and different income levels, one might worry that income inequality could affect local savings rates directly, and that a sex ratio imbalance is simply a proxy for earnings inequality. For a subset of provinces and years, we can measure local income inequality directly by the

Gini coefficient.7 In Column 3 of Table 2, we add the local Gini coefficient as an additional control. While the coefficient is positive – consistent with the idea that a greater inequality is associated with a higher savings rate, it is not statistically different from zero. With this much reduced sample, the coefficient on the local sex ratio is still positive and statistically significant. The point estimate jumps to 0.92.

In Column 4 of Table 2, we include local life expectancy as an additional regressor to account for the possibility that households save more when they expect to live longer.8 We also the share of local labor force enrolled in social security as a proxy for the extent of local social safety net. Neither coefficient is statistically different from zero.This suggests that inadequacy of social safety net does not appear to be as quantitatively important in explaining savings rates as commonly believed. We make this observation with one important caveat: this does not rule out the possibility that every region’s saving rate has been made higher due to a poor national social safety net.

Caroll, Overland, and Weil (2008) point out that, assuming habit formation in consumption, savings rate should tend to be higher in a fast-growing economy since consumption growth may not catch up with income growth immediately. In the last column of Table 2, we add the local growth rate of the preceding five years. This variable turns out to be insignificant, and the point estimate is in fact negative, which would have been consistent with a more standard model of consumption smoothing without habit formation. In any case, the coefficient on local sex ratio is still positive (0.34) and statistically significant. Across the columns in Table 2, the positive association between a high local sex ratio and a high local savings rate is robust and statistically significant.

Rural versus urban areas

Urban and rural areas differ in income, education level, and coverage of social safety nets. Parental preference for a son is also known to be stronger in rural areas. Perhaps most importantly, local marriage markets may work differently in rural and urban areas. A majority of marriages in rural areas take place between a man and a

7 The Gini coefficients are obtained from Ravallion and Chen (2007). The data are available for 29 provinces in 1988, 1990 and 1993, and 28 provinces in 1996 and 1999 for the urban sample, and 27 provinces in 1988, and 28 provinces in all other years for the rural sample. The overall Gini coefficients at the province level are approximated by weighted average of rural and urban Gini coefficients.

8 Life expectancy at the provincial level is only available in the three census years (1982, 1990 and 2000).

woman from the same county9. Most migrant workers either get married before leaving their homes to work in a city, or return to their villages to get married. In comparison, it is somewhat more common for marriages in cities involving a husband or a wife from outside the city. An implication of this difference in the marriage market is that the same local sex ratio imbalance may exert a smaller competitive pressure on men in a city than in a rural area. For these reasons, one may expect local savings rates to be more sensitive to local sex ratio imbalances in rural areas than in urban areas. Therefore, additional confirmation of the hypothesis may be obtained by running separate regressions for these two areas. The control variables are the same as those in Table 2 to the extent they are available for separate rural and urban areas.

The results are reported in Table 3. It is interesting to note that the estimated elasticity of local savings rates with respect to sex ratios is indeed greater for rural areas than for urban areas (0.75 versus 0.36, respectively, from Columns 2 and 4 of Table 3).

Instrumental variable regressions

The degree of a local sex ratio imbalance for the pre-marital age cohort (7-21) is pre-determined with respect to local savings decisions by construction, since the sex ratio is determined by parental decisions -- whether to undertake a sex selective abortion before a child is born -- taken many years prior to the corresponding savings variables in the regressions. This helps to justify the panel regressions reported in Tables 2 and 3. Nonetheless, one has to think hard about the possibility that sex ratio is endogenous, or that sex ratio is a proxy for something else that affects savings decision directly. For example, factors that affect sex-specific earnings in a region could simultaneously determine both a preference for sons and household savings decisions. In addition, as we noted earlier, local sex ratios may be measured with errors since they are inferred from the 2000 population census. In either case, the estimated elasticity of the local savings with respect to the local sex ratio may be biased.

A solution to both the endogeneity issue and measurement errors is to employ an instrumental variable approach, which we turn to now. A key determinant of the sex ratio

9 According to the China Population Census 2000, about 10% of people migrate to places outside their registered counties or districts in 2000. Among them, only 2.5% list marriage or family reunion as a major reason of migration.

imbalance is a strict family planning policy introduced in the early 1980s.10 We explore two determinants of local sex ratios that are unlikely to be affected by local savings rates, and for which we can get data. First, while the goals of family planning are national, the enforcement is local. Eberstein (2008) proposes to use regional variations in the monetary penalties for violating the family planning policy as an instrument for the local sex ratio. Using data collected by Scharping (2003) and extending them to more recent years, Eberstein focuses on two dimensions of penalties: (a) a monetary penalty for the violation of policy, expressed as a percent of annual income in the province, and (b) a dummy for the existence of extra penalty for having higher order unsanctioned births (e.g., for having a 3rd child in a 1-child zone, or for having a 4th child in a 2-child zone). These two variables are part of our set of instruments too. Second, while the Han ethnic groups faces a strict birth quota, the rest of the population (i.e., the 50 some ethnic minority groups) do not face or face much less stringent quotas. (The government allowed the exemption, possibly to avoid criticisms for using the family planning policy to marginalize minority groups). Since non-Han Chinese are not uniformly distributed across space, this variation offers one more possible instrument (Bulte, Heerink and Zhang, 2009).11

In Table 4, we report the first-stage regressions for the IV regressions that link local sex ratios to their determinants, with both financial penalties and minority shares lagged by 14 years (to match the median birth year for the age cohort 7-21). Both types of variables appear to be related to sex ratios. First, more severe financial penalties -- set in a decade earlier -- are indeed associated with a more unbalanced sex ratio. Second, the proportion of people not subject to birth quotas is negatively related to local sex ratio imbalance. The adjusted R-squared for the first-stage regressions is in excess of 60%.

In Column 1 of Table 5, we report the 2SLS estimation results for local savings rates where the local sex ratio is instrumented by the three variables described above.

10 China’s family planning policy, commonly known as the “one-child policy,” has many nuances. Since1979, the central government has stipulated that Han families in the urban areas should normally have only child (with some exceptions). Han Chinese are in the majority ethnic group, accounting for about 95%of the Chinese population at the time the policy was introduced. Families in rural areas can generally have a second child if the first one is a daughter (this is referred to as the “1.5 children policy” by Eberstein, 2008). Ethnic minority (i.e., non-Han) groups are generally exempted from birth quotas. Non-Han groups account for a relatively significant share of local populations in Xinjiang, Yunnan, Ganshu, Guizhou, Inner Mongolia, and Tibet.

11 In principle, variations in the cost of sex screening technology especially the use of an Ultrasound B machine, and the economic status of women (such as that documented in Qian 2008) could also be candidates for instrumental variables. Unfortunately, we do not have the relevant data. Note, however, for the validity of the instrumental variable regressions, we do not need a complete list of the determinants of local sex ratio in the first stage.

While a Durbin-Wu-Hausman test rejects the null that the sex ratio is exogenous (with a p-value of 0.03), a Hansen’s J statistic for over-identification fails to reject the null that the instrumental variables are valid (with a p-value of 0.30). With the 2SLS procedure, the local sex ratio continues to have a positive coefficient that is statistically different from zero. The point estimates, 0.74, is in fact larger than most corresponding estimates

in Table 2. This suggests that an attenuation bias from measurement errors might have outweighed an endogeneity bias in the original panel regressions. Based on the point estimate in Column 1 (0.74), an increase in the sex ratio for the age cohort 7-21 from

1.045 in 1990 to 1.136 in 2007, leads to a rise in the savings rate by 6.7 percentage points, accounting for 48% of the actual increase in Chinese savings rate during this period (details of the calculation can be found in Table 5a).

We also find that richer regions save more. A one percent higher per capita income is associated with a higher savings rate by 0.27 percent. Regions with more people working in the state sector save less. An increase in the share of state sector employment in local population by one percentage point is associated with a reduction in local savings rate by 0.24 percentage points. The last finding supports a precautionary savings motive: If more public sector employment implies less income and job uncertainty, then there is less need to save. We do not find evidence that the age profile

of the local population matters per se, which suggests that the life cycle hypothesis is not supported in the data (as in Chamon and Prasad, 2008).

In Column 2 of Table 5, we replicate the 2SLS estimation but excluding the share of minorities in local population from the set of instruments. Even though the Hansen’s J test in the first column suggests that all three instrumental variables, including the minority share, are valid in a purely statistical sense, we act conservatively here and allow for the possibility that non-Han Chinese have a different desired rate of savings and thus should not be in the set of instruments. In this case, the local sex ratio continues to exhibit a positive and statistically significant coefficient, with the point estimate becoming even larger (0.89). An increase in the sex ratio for the age cohort 7-21 from 1.05 in 1990 to 1.14 in 2007, would now lead to a rise in the savings rate by 8.0 percentage points (=0.09 x 0.89 x 100), accounting for 50% of the actual increase in Chinese savings rate ( =6.66/[(0.31-0.15)x100] ). With household level regressions to be

reported later (Tables 7-9), we find no robust evidence that savings by households headed by ethnic minorities behave differently from their Han counterparts in a given location. In other words, minority shares are unlikely to affect savings rates directly without going through local sex ratios. Therefore, we prefer those 2SLS estimates in Column 1 in which all three instruments are used.

In Columns 3 and 4 of Table 5, we apply the three instruments for sex ratio to

2SLS estimation where the dependent variable is either the rural or the urban savings rate. We confirm the results in the earlier panel regression: a higher local sex ratio raises local savings rates in both areas. The reaction of the local savings rate to a change in the sex ratio is stronger in rural areas. An increase in the rural sex ratio from 1.048 to 1.141 (the actual mean increase from 1990 to 2007) would lead to an increase in the rural savings rate by about 6.6 percentage points, or about 53% of the actual increase in the savings rate during this period12. For the urban areas, an increase in the sex ratio from 1.037 in 1990 to 1.113 in 2007 would raise the savings rate by 4.6 percentage points, accounting for about 26% of the actual rise in the savings rate. (Table 5a presents the calculations).

Household-level evidence

It is useful to go beyond regional aggregate comparisons and look at evidence at the household level. From data in the Chinese Household Income Project (CHIP) of 2002, which covers 122 rural counties and 70 cities,we construct a sub-sample of households with one or two children and a household head younger than 40.13Since most unmarried young people live with their parents, the survey does not contain many observations of an unmarried young man or woman as the household head. Therefore, we are not able to analyze such households directly.

One may be tempted to compare savings rates for households with sons and those with daughters. But this comparison is not particularly informative for our hypothesis. Under the hypothesis of a competitive saving motive, one expects that families with a son

12 In the rural savings equation, it is useful to note that the Durbin-Wu-Hausman test does not reject the null that the sex ratio regressor is uncorrelated with the error term in the original OLS (panel) regressions in Table 3. In this case, one may prefer the estimates in Columns 1-2 of Table 3 on the efficiency ground. (At it turns out, the Hansen’s J test in Table 5 suggests that the IV’s do not work well for the rural savings regression.)

13 We place an age limit of 40 for heads of households with an aim to exclude households with some older children (who have left home) and some younger ones. They may not be comparable to households with only younger children.

to save more, if other things are held constant. However, other things cannot be held constant because parents may not expect to get the same degree of help from their daughters than from their sons as they age, especially in a rural area where a woman moves to live with a man’s family after the marriage. In other words, families with only daughters may need to save more to prepare for old age. For this reason, a direct comparison of the savings rates between these two types of households is not informative for our purpose.

In any case, Table 6 reports average saving rates for households with children of different genders. In both rural and urban areas, households with a son have a moderately higher savings rate than those with a daughter (37% versus 33% in rural areas, and 30% versus 26% in urban areas). However, none of the differences in savings rates is statistically significant; the standard deviation of the savings rate within any type of household easily overwhelms the difference in the savings rate between any two types of household. Of course, large standard deviations also suggest the presence of considerable noise in the savings data. In any case, we cannot confirm or reject our hypothesis by comparing the savings rates across household types in this way.

Our hypothesis, however, implies a particular regional variation in saving rates: households with a son should save more in a region with a more unbalanced sex ratio, holding constant family income and other characteristics. Moreover, this pattern is not predicted by either the life-cycle theory or by existing precautionary savings motive hypotheses. Therefore, examining the relationship between household savings rates and local sex ratios may be particularly informative for testing our hypothesis.

We can also examine the relationship between the savings rate by households with a daughter and the local sex ratio. This helps us to check the presence of a spillover channel in savings pressure from households with a son to other households. If the spillover channel operates through housing prices, it is likely to be stronger in the urban areas as houses are more likely to be purchased from the local market (as opposed to being built on the occupants’ own land in rural areas).

The regression results for the rural sample are presented in Table 7. The first four regressions are performed on a full sample. The last four regressions are on a sample where the top and bottom 5% of savings rate outliers are removed. Since the large

standard deviations in the savings rates reported in Table 6 likely reflect noise, we place more trust in the results from regressions where the outliers are removed. We therefore focus our discussion on the results reported in the last four columns of Table 7. (The results from the first four columns largely confirm the same patterns.) The regressions control for family income, children’s ages, characteristics of the head of household (sex, education, and ethnic background), and local income inequality. It also controls for health shocks to the family by a dummy denoting “poor health” if the family has a disabled or severely ill member.

Column 5 of Table 7 relates savings by households with a son to local sex ratios and other determinants of savings rate. We find that the local sex ratio has a strongly positive effect on the household savings rate. An increase in the local sex ratio from 1.05 to 1.14 (the mean increase in rural China from 1990 to 2007) is associated with a higher household savings rate by 12.2 percentage points, which is economically large. In comparison, Column 6 of Table 7 reports the regression concerning savings by households with a daughter. The coefficient on the local sex ratio is negative (-0.05), consistent with the possibility that households with a daughter take advantage of a higher sex ratio imbalance in their favor by saving less. (Surveys of rural households in Guizhou province of China conducted by one of the authors in 2005 and 2007 show that a bride’s family often expects a financial transfer from a groom’s family). However, the coefficient is statistically insignificant. This may reflect an offsetting effect from a spillover in the savings pressure that we have discussed.

In Columns 7 Table 7, we report a regression on savings by households with two daughters. The coefficient on local sex ratio is more negative in this case (-0.36) than in the one-daughter case (-0.05). This is consistent with the notion that a higher sex ratio imbalance per se raises the bargaining power of the families for every daughter they have. However, the coefficient is still statistically insignificant, possibly reflecting a strong offsetting effect from the spillover of competitive savings by families with a son.

In Columns 8 Table 7, we report a regression on savings by households with a son and a daughter. (It is relatively uncommon in the sample to have two sons due to the family planning policy). The coefficient on the local sex ratio is positive (0.16),

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者,传递爱与力量,而做到这些,除了付出等质的热血与辛劳,别无他法。 同为战争时期的又一强大的女性:南丁格尔就诠释了这种奉献。出身名门的她不图回报,在战后默默地用自己的力量支持着战士们,她照料垂死病人,终日奔忙,她在物质生活里的需求如此微少,她坚持等到最后一名战士离开,她才离开战场。她的精神已经超脱了自我,她的奉献与牺牲在精神世界里显得无比巨大,她用爱的掌声抚平了战士们的伤痛,伤病员写道“那些寒夜因为她而充满了温暖……” 人世间正是因为有了这样的鼓掌者,有这样将把自己的精神力量奉献给别人的人们啊,生活的希望才如此朝气蓬勃。“生命的用途其实不在长短,而在于人们怎么用它,许多人活的日子不多,却活了很久。”假如我有能力成为谁心中的精神支柱,我将努力的把这个神圣的任务做好。 是啊,我们在低潮的时候需要鼓励,需要正能力的支持,所以我们要友善的给四周的人一些正能力。 【篇二】 现代社会的节奏快速跳动着,许多人都忙繁忙碌地过完一天又一天3951为事业、学业和家庭而奋斗着,因此堆积的压力就越来越多3很少有人有乐观的生活态度积极安康的为人处事。因此,生活反而会成为一种承担!所以,生活需要“正能量”! 何谓“正能量”?这词原本是天文学的专有名词,后来英国的学

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以正能量为话题的心得作文精选5篇 以正能量为话题的心得作文精选1 寻找微尘的踪迹,我们发现了这样一个新名词——正能量。它把微尘融入其中。起初微尘是青岛一位数次捐款不留姓名的普通市民;后来,逐渐扩展成一个关爱他人的爱心符号。再后来,以微尘命名的爱心群体,走进青岛的大街小巷。 20_在我们身边,红飘带、微尘等越来越多的人积极投入到传播“正能量”的洪流中。 盛夏的青岛,少了几丝清风拂面,多了几分蝉的嘈杂。我正准备和妈妈去补习班,车子走到中途,上来一位带着孩子的妇女。我看见前面的一个年轻的哥哥站起来给她们让座。过了两站,那位让座年轻人下去了,车子重新行驶起来。突然,车子突然猛烈地歪斜了一下,我本能的向前看去,本想知道发生了什么,却看到这样一副景象:在急刹车时,我前面的小孩重心不稳的向前面的栏杆撞去,还发出了呼救声,而他旁边的另一位年轻人则毫不犹豫的伸手挡在了栏杆上,让那个小孩撞在了他的手上,幸免了一场悲剧。

如果让我来评论,那他一定是“最美乘客”。在当今社会,有很多侠肝义胆的热心人,在他们身上蕴藏着的“正能量”,正在温暖我们这个社会,改善我们这个社会。 正能量是指引人们前进的灯塔、是鼓动人们前进的风帆和是团结各种力量共同奋斗的纽带。社会需要爱,时代呼唤爱。赠人玫瑰,手留余香。在当今社会,我们需要正能量。 生活中,“正能量”带来的正效应确实不少。正如我们在生活中,阿里木带给我们的感动,他靠卖烤肉资助贫寒学子,而不少人专程去“捧场”,这里面有感动,也有“正能量”的传递。还有黑龙江最美女教师张丽莉,为救学生被压断双腿。 其实,在我们有困难时、无助时、烦闷时,在我们渴望他人帮助时,我们也需要一个充满正能量的环境,这样,这些烦恼就可以化为乌有了。 现在,当美丽这一并不新颖的词汇与中国、青岛相连时,给人的感受是全新的,它不仅是一个形容词,更是一个动词! 以正能量为话题的心得作文精选2 记得有一次我们全家去植物园,在路上,看见一个树桩,我指着树桩横截面上一圈圈的痕迹,好奇的问妈妈,这是怎么出来的?妈妈听了,笑了一笑,指着树桩上的圈圈说:这是树的年轮,它显示了树的年龄。

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后轴不平衡率=(过程差值大-过程差值小)÷最大行车制动力中大的值×100% (2)后轴行车制动率<60%时 后轴不平衡率=(过程差值大-过程差值小)÷【轮荷之和×0.98】×100% 注:(1)机动车纵向中心线位置以前的轴为前轴,其他轴为后轴; (2)挂车的所有车轴均按后轴计算; (3)用平板台测试并装轴制动力时,并装轴可视为一轴 整车制动率 整车制动率=最大行车制动力÷(整车轮荷×0.98)×100% 驻车制动率 驻车制动率=驻车制动力÷(整车轮荷×0.98)×100% 台式检验制动率要求(空载) 台式检验制动力要求(加载)

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制动力矩计算

鼓式制动器制动力矩的计算 1、制动器效能因数计算 根据制动器结构参数可知: A 、 B 、 C 、r 、φ、(结构参数意义见附图二) 其中θ为最大压力线和水平线的夹角。 由以下公式计算μ=0.35时(μ为摩擦片与制动鼓间摩擦系数),制动器领蹄和从蹄的制动效能因数。 θ=)tan(B C ar μγt a n ar = )t a n s i n s i n t a n (θφφφφθ+-=ar e θθγλ-+=e θθγλ+-=e ' φφφρsin 2sin 4+= r B A +=ξ r C B k 22+= 领蹄制动效能因数: 1sin cos cos 1-=?γ θρλξ?e k K

从蹄制动效能因数: 1 sin cos 'cos 2+=?γθρλξ ?e k K 制动器的总效能因数,可由领、从蹄的效能因数按如下公式计算: 2 11 24??φ?????+?=K K K K K 2、制动器制动力矩计算 单个制动器的制动力矩M 为: R P K M ??= 其中:K 为制动器效能因数 P 为制动器输入力,加于两制动蹄的张开力的平均值; R 制动鼓的作用半径,即制动器的工作半径r 制动器输入力η??=i F P /2 其中:F 为气室推杆推力,由配置的气室确定 i 为凸轮传动比,e L i /= (L 为调整臂臂长,e 为凸轮力臂,即凸轮基圆半径) η为传动效率,一般区0.63 例:某Φ400X180制动器,A=150 B=150 C=30 r=0.2 Φ=115° μ=0.35 η=0.63 通过上公式计算得1??K =1.530 2??K =0.543 2 11 24??φ?????+?K K K K K ==1.603 取F=9900N(0.6MPa 气压下气室输出力) L=125 e=12 R P K M ??==R L F K ????η/2e=1.603*9900*125*0.63*0.2/(2*12)

制动力计算方法

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为f1和f2,如果f1 >= f2 不平衡率 = (f1 –f2)/轴重 * 100 ;如果f1 < f2不平衡率 = (f2 –f1)/轴重 * 100 注意:以上为简约的计算,较为准确的计算要注意单位之间的换算:轴重是kg,制动力的单位是10N 例如: 轴重最大左最大右差值左差值右制动率不平衡率 2074 543 508 543 508 50.7 1.7 二轴不平衡率( 543-508)*10/(2074*9.8)*100= 1.722% 有关制动台仪表 制动台仪表的不平衡率算法说明书没有给出,不清楚其算法,对于前轴有可能是对的,对于后轴等仪表算法可定是错误的,制动台本身不能得到车辆的轴重,也就不能判断制动率是否 >=60,也就不能得出不平衡率。

传播正能量--作文

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蒲松龄,历史巨著《聊斋志异》的作者,创作时条件异常艰苦,但这并没有成为他向命运屈服的理由,反而他更坚强,意志更坚定,凭借一个小茶馆用一杯杯茶水换取路人的一个个神奇故事,终于克服种种困难完成了这本巨著,蒲松龄这种坚持不懈不向命运低头,不屈服于条件的精神品质感动了无数后人。 从古至今,有许多古人和后者都在默默的传递正能量,而我,只想做这大链条上的一份子,在生活中,在社会上把这份正能量,这份温暖这份爱悄无声息的接力下去,我很期待一个充满正能量的世界,让我们都行动起来,唤醒每个人内心深处的良知,一起携手,把正能量传递下去!

制动器制动力矩的计算

制动扭矩: 领蹄: 111????=K r F M δ 从蹄:222????=K r F M α 求出1??K 、2??K 、1F 、 β θ 2F 就可以根据μ计算出制 动器的制动扭矩。 一.制动器制动效能系数1??K 、2??K 的计算 1.制动器蹄片主要参数: 长度尺寸:A 、B 、C 、D 、r (制动鼓内径)、b (蹄片宽)如图1所示; 角度尺寸: β 、 e (蹄片包角)、α(蹄片轴中心---毂中心连线的垂线和包角 平分线的夹角,即最大单位压力线包角平分线的夹角,随磨擦片磨损而增大); μ为蹄片与制动鼓间磨擦系数。 2.求制动效能系数的几个要点 1)制动时磨擦片与制动鼓全面接触,单位压力的大小呈正弦曲线分布,如图2,max P 位于蹄片轴中心---毂中心连线的垂线方向,其它各点的单位压力 σsin max ?=P P ; 2)通过微积分计算,将制动鼓 与磨擦片之间的单位压 力换算成一个等效压力, 求出等效压力的方向σ 和力的作用点1Z 、2Z (1OZ 、2OZ ),等效力 P 所产生的摩擦力1XOZ (等于μ?P )即扭矩(需建 立M 和蹄片平台受力F 之间的关系);实际计算必须找出M 与F 之间的关系式: ????=K r F M

3)制动扭矩计算 蹄片受力如图3: a. 三力平衡 领蹄:111OE H M ?= 从蹄:222OE H M ?= b. 通过对蹄片受力平衡分析(对L 点取力矩) ()1111G L H b a F ?=+? ()1111/G L b a F H +?= ∴ ()11111/G L OE b a F M ?+?= 111????=K r F M ∴ 111 1G L OE r B A K ? += ?? 同理: 2 22 2G L OE r B A K ? += ?? c. 通过图解分析求出1OE 、2OE 、11G L 、22G L 与制动器参数之间的关系,就可以计算出1??K 、1??K 。 3.具体计算方法: 11-?= ?ρ γ?K l K ; 1'2+?= ?ρ γ?K l K r B A l +=; r C B K 2 2+= 1) 在包角平分线上作辅助圆,求Z. 圆心通过O 点,直径=e e e r sin 2sin 4+?

传播正能量文章

传播正能量文章 有时候,我们就是需要一些正能量的文章来充实自己,来让自己也学会做一个励志的人。下面是为大家整理的关于传播正能量文章的相关资料,供您参考! 传播正能量文章篇1:我们还能混多久 混,也可谓一种生活,但真正的生活是混不了一辈子的。现在开始混日子,老来之时,遍是无日子可混,无生活可享,从而后悔莫及,遗憾终生。 越来越习惯安逸,越来越害怕冒险,越来越逃避责任,越来越淡化理想,开始所谓的平静生活,平淡心态,而事实却只是自欺欺人。当一天和尚撞一天钟,日复一日,年复一年,看似无欲无求,实则内心彷徨;看似随遇而安,实则斗志丧失;看似平静淡雅,实则危机四伏。自古有云,居安思危,而现在已慢慢忘却了梦想,渐渐融入了安逸,对于安逸之中隐藏的危机,视而不见,直至危机四伏,才措手不及,深感后悔,却是悔之晚矣。时常反思现在的自己,偶尔遐想未来的自己,细细品味却发现,那只是一个空洞的梦想,可望而不可及,可求而不可遇,若以目前的状态继续前行,无论何时都不可能达到自己预期的目标,看看现在,想想未来,就会控制不住的心慌,情不自禁的烦躁,在理想与现实中矛盾着,在感性与理性中纠结着,在忘我与自我中无奈着,想要改过自新,却是无从下手;想要痛改前非,却是无

力回天。 现在的自己如同温水中的青蛙,在慢慢等待着死亡来临的那一刻,每天过着同样的日子,虽有小波澜,却难以引起足够斗志;每天都会无所事事,虽偶有忙碌,却只是闲多忙少;上班时盼望着下班,下班后期盼着自己的小天地,将烦恼抛却,将思绪放纵,一天中最幸福的时刻或许只有睡觉,忘却了现实,超脱了自我,偶尔做个美梦,将灵魂尽情翱翔于梦境深渊。而自己很清楚,这只是在逃避,逃避现实,躲避责任,长此以久,必然是碌碌无为,庸碌一生,想要终结,却是举目无措,明知是错,却不思悔改,明知失败,却一意孤行,内心痛苦而无奈,却不知如何自救。 现实中或许有很多人同我一样,混沌的过着日子,得过且过,盲目的追随着目标,却看不到前方的路,混着日子,却做着白日梦,下着慷慨的承诺,过着我行我素的生活,表着激昂的决心,继续着唯我独尊的日子,不思悔改,不求上进,偶尔静心反思,才知自己已远离目标,寂夜反省,才觉自己已走入歧途。明明是亡羊补牢,为时不晚,却总是心有余而力不足。混沌的日子,究竟何时了结?庸碌的岁月,究竟何时终结? 古语有云:人贵有自知之明。而事实呢,我们往往自知而不自制,又有何用?平凡的人满地都是,而真正的人才却是屈指可数,在身体上人与人之间都是相差无几的,而欠缺的只有思维,人因为有了独立思考的能力,故而高级,故而神秘,也就是因为思维而将人类划分开来。每个人都或多或少的存有压力,而又有几人能将压力化作紧迫感,

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