Education and Social Capital

Education and Social Capital

Catherine Burnheim

October 2004

This paper asks: How has social capital been used to analyse education? Given the origins of social capital in educational sociology, how is social capital theory being used now in studies of education?

These questions arise from two sources. Firstly, three striking coincidences from my reading on social capital:

?Robert Putnam’s contention in Bowling Alone that the term “social capital”

was first used in the context of community education (Putnam 2000) ?The concern of both seminal theorists of social capital with educational attainment and social inequality (Bourdieu 1986; Coleman 1989) ?Again in Bowling Alone, Putnam’s finding that e ducation is the clearest proxy measure for social capital (Putnam 2000).

Secondly, in negotiating the vast (and growing) social capital literature, an attempt to discern whether the literature had provided different or just more of the same perspectives on the relationship of sociability and learning.

Social capital has been used as a way to illuminate the relationship between the micro level of educational experience and the macro level of social forces and structures. A common starting point for both Bourdieu and Coleman was the rejection of the idea that educational attainment and achievement is a product solely of individual’s natural talents. Aspects of the explanations Bourdieu and Coleman offer are similar, despite different theoretical frameworks. Subsequent theorists have refined the concept of social capital and applied it in different ways. Although a large volume of these studies replicate previous work (p articularly Coleman’s), others ,eg Stanton-Salazar and Dornbusch (1995), extend and question it. Social capital has become an important concept in educational policy, with substantial work by the OECD and others investigating the relationship of human and social capital.

This paper reviews the development of social capital in the educational literature. Part 1 presents an argument, drawing on James Farr’s conceptual history, that education has always been closely linked to social capital. Part 2 offers an analysis of the similarities and differences in the conceptualization of social capital in the work of Bourdieu and Coleman. Part 3 charts how these different conceptualizations have been taken up in subsequent literature and in policy and offers directions for further inquiry.

1. Early links

Robert Putnam in Bowling Alone (Putnam 2000) cites an obscure rural educator, Lyda J Hanifan, as the first use of the term “social capital” in an 1916 essay about the development of schools as community centres. Putnam’s genealogy has become the canonical one, cited in much of the subsequent literature, but in a recent article, conceptual historian James Farr has shown the limitations of Putn am’s research (Farr 2004). Farr demonstrates that the term “social capital” was in much wider use in the period, importantly by John Dewey who was a leader in the movement of which Hanifan was a part. Farr surmises that Hanifan drew the term from Dewey’s work. As well, he traces other uses of the term, including by Marx, and another contemporary sense of the term in relation to collective ownership of property, and the collective profit from labour. Farr’s exploration of the history of the concept adds significantly

to our understanding of social capital, as it shows that the conjunction of social benefit and economic language was more widespread earlier than attributed by other theorists, as well as placing Dewey’s critical pragmatism into the family tree of the concept.

It is also significant that the term gained currency within a movement that was about community education and rural community building. The social centre movement advocated expanding the role of schools from a focus on educating children to being places of social development and learning for all members of society. In Hanifan’s “rural educator’s dream”, according to Farr, the school became the centre of society. The social centre movement linked many other movements, including the university extension movement and also related to the community civics movement which aimed to replace “old civics” of governmental formality with “new civics” focussed on community life and active learning. It adopted the methods of progressive education, in particular what is now called “service learning”. Students worked in groups addressing social problems using learning-through-doing. Aspects of this movement are still strong in the USA, with organisations like Campus Compact actively involved in promoting service learning and civic engagement.

The inspiring theorist of these movements was John Dewey, who was himself extensively involved in some of them. Dewey himself used the term (see quote p 10) and his conceptual framework and language drew upon and developed the idea of work together creating common bonds (of sympathy and cooperation) which were a resource for people in communities. Farr draws out three important points about Dewey’s use of social capital: firstly, that criticism must be balanced with construction, second, the importance of s ympathy, third, the combination of “social” and “capital” for rhetorical effect. Dewey focussed on the relationship of school and society, and the potential contribution of education to enable rather than fetter social capital. Balancing criticism and construction is at the heart of critical pragmatism –(p10) crisis gives rise to critical reflection which creates ideas to guide action to address the crisis. Sympathy “entailed the ordinary sense of feeling concern or compassion for others, especially those denied or deprived life’s essentials, including social capital”, but also the capacity of imagination that allows people to relate to and appreciate commonalities with others in different circumstances ( p11).

In schools - “….each individual gets an oppo rtunity to escape from the

limitations of the social group in which he was born, and come into contact

with a broader environment.” (Democracy and Education, 1916, p20) (See

also JS Mill) – Prefigures discussion of Bonding and Bridging social capital.

Farr shows Dewey’s use of economic terminology as a “terminological strategy” of critical pragmatism (12), citing other examples like that of “unused talent” as “wasted capital”.

The Dewey/ Hanifan use of “social capital” is very close to Putnam’s, idealising as it does particular forms of social interaction and community life, the interaction between institutions (of education and of governance) with citizens both individually and collectively, and the potential re-shaping of these institutions to meet collective needs.

I will skim over the “middle period” of social capital’s development. Between the 1920s and 1980s the term was used by assorted sociologists and others – notably Glen Loury and Jane Jacobs(Jacobs 1964). None of these writers had a particular interest in education. Another important development in the period however was the development and increased currency of the term “human capital”. Gary Becker is credited with developing the theory of expenditures on education, training, health etc as investments in human capital, with a logic of returns similar to that of physical capital. (Becker 1964). This was an important precursor to the work of Coleman in particular.

2. Coleman and Bourdieu

The two major strands of thought on social capital were developed in the late 1980s, by sociologists of education Pierre Bourdieu and James Coleman. Bourdi eu’s most detailed discussion of social capital appeared in his 1986 essay “The Forms of Capital” which was translated by Richard Nice and published in an English language anthology (Bourdieu 1986).Coleman’s article, “Social c apital in the creation of human capital”, was published three years later in the American Journal of Sociology (Coleman 1989). Although they co-organised a conference in 1989 in Chicago and co-edited its proceedings (Bourdieu and Coleman 1991), the development of the two conceptions has happened independently and without reference to the work of the other. Indeed, a striking aspect of the literature is how comprehensively the two strands have ignored each other, particularly to the neglect of Bourdieu (Fine 2001; Field 2003). The result of this is that the Coleman tradition constitutes the largest part of the social capital literature since the 1990s, largely because of Coleman’s influence on Robert Putnam but also because of the continuing influence of Coleman’s original studies, as discussed below. Although Field (Field 2003) categorises Putnam’s work as a third strand to that of Bourdieu and Coleman, I would argue that Putnam follows on directly from Coleman in his concerns with neighbourhood influences and voluntary associations, as well as his conflation of the sources and benefits of social capital.

Definitions

Bourdieu’s and Coleman’s definitions of social capital are similar in that they both emphasise the functional value of social relations as resources available to agents. In Bourdieu’s words:

"Social capital is the aggregate of the actual or potential resources which are

linked to possession of a durable network of more or less institutionalized

relationships of mutual acquaintance and recognition - or in other words - to

membership in a group - which provides each of its members with the backing of the collectivity-owned capital, a "credential" which entitles them to credit,

in the various senses of the word." (Bourdieu 1986)

Similarly, Coleman defines social capital as connections –“social capital inheres in the structure of relations between and among actors” (p98) – and its use value: Social capital is defined by its function. It is not a single entity but a variety of different entities, with two elements in common: they all consist of some

aspect of social structures, and they facilitate certain actions of actors -

whether personal or corporate actors - within the structure. (p 98). (Coleman

1989)

Later iterations (for example Woolcock, OECD, Foley and Edwards) have sharpened these definitions, distinguishing more clearly networks and the norms which create reciprocity as the two elements of social capital. Portes has emphasised the need to separate membership of a network or group as the source of social capital and the benefits which may be gained from this membership (Portes 1998). Going one step further, Foley and Edwards offer the formula "Social capital is best conceived as access (networks) plus resources." ((Foley and Edwards 1999) p 166). Putnam argues for the inclusion of trust – social capital as networks, norms and trust. (Putnam 2000), but Woolcock prefers an even sharper definition, defining trust as a product rather than a constitutent part of social capital (Woolcock 1998).

Fungibility

Both Coleman and Bourdieu have an instrumentalist view of social capital as a resource, inherent in social relationships, which can be used by individuals and institutional agents to various ends. Both see social capital as interacting with and transactable for other forms of capital, although this Bourdieu elaborates the dynamics of this interaction in far more detail.

Coleman is particularly concerned with the interaction between social capital and human capital, although he acknowledges that these transactions may be limited: “like physical capital and human capital, social capital is not completely fungible but may be specific to certain activities. A given form of social capital that is valuable in facilitating certain actions may be useless or even harmful for others.” (p 98). Coleman shows that social capital is not just a property of the elite, and to some degree compensate for the lack of other forms of capital.

Coleman uses the framework of rational action, although “without the assumption of atomistic elements stripped of social relationships” (Coleman 1989). His view of social capital emphasises the importance of network closure (ie that your friends know your other friends, and in particular that you are friends with parents of your children’s schoolmates). Coleman identifies three key aspects of social capital: obligations and expectations (which depend on the trustworthiness of the social environment), the information-flow capability of the social structure, and the presence

of norms accompanied by sanctions. The classic example he offers is that of diamond traders in New York, where a dense network enables the operation of collective norms and effective sanctions so that the market operates with a high degree of trust. Thus the context of relationships creates incentives and sanctions which guide individual rational behaviour.

In contrast to Bourdieu’s interest in class groupings, Coleman is concerned primarily with the family and neighbourhood. For Coleman it is the presence of effective norms and sanctions within the immediate family that is most important for educational attainment. He emphasises the role of mothers in particular in fostering this environment. Coleman argues for a differentiation between “primordial” –“social organization that has its origins in the relationships established by childbirth” (p 1) –and “constructed” social structures – those which are constructed for either a single purpose or a narrow range of purposes” (p 3) (Bourdieu and Coleman 1991). Unsurprisingly, Coleman’s work has been subject to feminist critiques (eg Morrow) arguing that his view of the family is highly patriarchal. Other critics have questioned Coleman’s valorisation at close (bonding) ties rather than weak (bridging) ties (Portes, Stanton-Salazar).

In Bourdieu’s schema, social capital interacts with economic and cultural capital. In fact, social capital is a less important aspect of Bourdieu’s theory of social structure than cultural capital. In Bourdieu’s terms, actors compete for capital within “fields” of activity. Complex societies are composed of a number of fields, each with their own specific logic (Bourdieu and Wacquant 1992). Although some fields may have dominance (eg the economic field in capitalist economies) (p 109) and the State has a role in regulating the operation of all fields, they are never entirely reducible to one dynamic (p 97). These fields are configurations of relationships in which positions are defined by the distribution of capital in different forms across the actors (individual or institutional) in a field (Bourdieu and Wacquant 1992). Some actors have more capital and so are dominant over those with less; others may have equal but different compositions of capital at their disposal which puts them in a different relationship to other actors and the field itself. The actor’s position is historically determined: th at stock of capital has been accumulated or reduced over time through exchanges which are shaped by the existing relationships and by the “rules of the game” – the relative value of different forms of capital and the ability to convert capital from one type to another.

Differences: agency, boundaries

The key differences between Bourdieu’s and Coleman’s conception of social capital stem largely from their philosophical stances. Bourdieu emphasises access to institutional resources; Coleman emphasises norms (Dika and Singh 2002). As outlined above, Bourdieu conceptualises social capital as operating in a social field which is hierarchically structured. Like other forms of capital, social capital is held disproportionately by elites. The tendency is for the existing power relations to reproduce themselves; there is little sense in Bourdieu that the existing structure can be challenged (Jenkins 1992)

An interesting difference between the two is the extent to which development of social capital is a deliberate strategy (Baron, Field et al. 2001). Coleman sees social

capital as a by product "a largely unintentional process” (Baron, Field et al. 2001)p 7), as individuals are primarily concerned with advancing their own interests. He gives the example of a mother returning to work, and as a result relinquishing her active role in school activities. Even though the action is rational in relation to her own and her family’s interests, it causes a net loss of social capital for the other families associated with the school.

Bourdieu sees "an endless effort at institution" - "the network of relationships is the product of investment strategies, individual or collective, consciously or unconsciously aimed at establishing or reproducing social relationships that are directly usable in the short or long term". (Bourdieu 1986) 249. Bourdieu emphasises the non-conscious aspects of the transmission of cultural capital – that children in cultural capital-rich environments tend to absorb the advantages unknowingly. He sees the education system as about the transmission of cultural capital – examinations etc are “collective magic” making cultural capital visible and validated. He argues that the education system increases in importance when social hierarchies based on descent are challenged.

Bourdieu is highly critical of rational action theory (RAT), the tradition of which Coleman is a part, although Jenkins argues that some of the accusations Bourdieu makes can be turned back on him (Jenkins 1992). Bourdieu argues that RAT substitutes an arbitrary rationality/ interest for a culturally/ historically located one. In so doing, RAT substitutes its analytical model for reality and locates the dynamic of social life in “pure” individual and conscious decision-making rather than in the individual and collective histories that generate social reality. This prevents a theoretical apprehension of relations between individuals and between individuals and their environment. (Jenkins 1992) However, Jenkins argues that in totally rejecting RAT Bourdieu creates a problem for his theory, because he denies that conscious decision-making does have a role - people do form plans and try to implement them. (Jenkins 1992)

Jenkins is somewhat unfair –Bourdieu’s theory of interest is more sophisticated than that.

Similarly, Bourdieu is suspicious of coherent groupings, emphasising how groups gate-keep and exclude, whatever the internal benefits to those on the inside.

This is key difference between the two – Coleman wants more social capital; Bourdieu questions what sort and for whom.

3. How “social capital” has been taken up in the educational literature

Baron, Field and Schuller offer a three-way typology of how social capital has been used in the literature: analysis, prescription, and heuristic (Baron, Field et al. 2001). I will use this framework to analyse the recent literature on social capital and education, drawing in parti cular on Dika and Singh’s excellent survey of journal articles on education and social capital in the period 1990 to 2001 (Dika and Singh 2002).

Analysis

A large amount of the social capital and education literature has been devoted to largely re-running Coleman’s studies (Dika and Singh). There has been particular interest in different migrant populations in the USA. Like Coleman’s original work, these studies have used large US datasets not originally designed to capture social capital aspects. The indicators used by Coleman are: (within family) parents’ presence, number of siblings, mother’s expectation for child’s education and (outside family) number of moves (proxy for intergenerational closure). Coleman’s work on the differential performance of students in Catholic and other religious schools has also been replicated (Coleman 1989; Coleman 1990). As recently as two months ago the Catholic Education Office in Victoria has published similar work on the relative effectiveness of Catholic schools (Sheehan 2004).

In contrast to Coleman’s focus on “bonding” social capit al, Stanton-Salazar and Dornbusch studied educational attainment and social capital considering students’ own social networks and their “bridging” access to information-related support including personal advice about academic decisions, future educational and occupational plans and access to legal, health and employment services (Stanton-Salazar and Dornbusch 1995). They found a more complex picture, in which bilingualism and associated cultural capital was a key factor in students’ access to sources of information and to institutional resources (p132) Grades were positively related to three different informational network variables: number of school-based weak ties, number of non-kin weak ties, and proportion of non-Mexican origin members. Dika and Singh point to the work of Stanton-Salazar and Dornbusch as an example of how Bourdieu’s theory of social reproduction and the interplay between cultural and social capital can be used to illuminate institutional aspects of social capital formation (Dika and Singh 2002).

Prescription

Social capital is a concept of great interest to policymakers – even being described as the “missing link” (Grootaert and Van Bastelaer 2002) – and it has been enthusiastically embraced by organisations like the World Bank and the OECD. The use of social capital in policy development, particularly by the World Bank has been trenchantly criticised (Fine 2001; Harriss 2002). Some like Field have warned that social capital can only act as means to leverage existing resources, not create new ones (Field 2003). Despite this, Harriss argues that social capital theory has led to a programmatic emphasis on local development and "self-help":

"even though this sometimes looks rather like expecting the most

disadvantaged people to pull themselves up by their own boot straps, in a way

which is remarkably convenient for those who wish to implement large-scale

public expenditure cuts." (Harriss 2002).

There has not been a similar strenous reaction against the policy prescriptions of the OECD in social capital and education. There is a substantial OECD literature on social capital and human capital, notably from the Quebec symposium of 2000 (Helliwell 2001). This literature is stimulated by the idea that education is one of the few intervention points for the creation of social capital (Schuller 2001). This tradition follows very much in the footsteps of Dewey and Hanifan, advocating education as a

central aspect of social renewal. School as an intervention point – but risk of overburdening schools (Pamela Munn p 181).

Heuristic

Social capital has been seized on as a way of reinstating different forms of education into the debate, in particular continuing, adult, informal and vocational education (Winch 2000; Balatti and Falk 2001; Kearns 2004). For example, in a review of Christopher Winch’s book on vocational education and social capital, Richard Barrett writes that Winch achieves his aim of making vocational education a subject to be “given its deserved seriousness by philosophers of education” through his arguments about the civic aspects of vocational preparation (Barrett 2004). Schuller et al’s synthesis of their longitudinal research on the benefits of learning includes both “taught” and “non-taught” learning (Schuller 2004).

There have been fewer studies of the institutional implications of social capital. Barry Golding’s work on networks in ACE is an exception (Golding?), as is Persell & Wenglinsky’s study of the civic engagement of students at different types of colleges (reference). Barry Golding has examined the value of using network mapping in adult education and learning community settings to conceptualise discontinuities in relationships between communities and organisations in a particular region (Golding?). Persell and Weglinsky found that type of institution attended had an impact on civic engagement, with students attending for-profits less likely to vote or participate in political processes than community college students.

4. Directions for further investigation

Taking the definition of social capital as networks and norms, clearly education has a role in the creation of both. The relationships formed at school and through other forms of education are important for immediate social support and for linking to institutional resources. At the same time, the educational process forms ideology, habits, behaviours and models of cooperation and conflict.

I would suggest a number of directions for further investigation of the relationship between education and social capital.

?Further exploration of Dewey’s work and its relationship to social capital, in particular Bourdieu. There is an interesting link between Bourdieu and Dewey.

(Perhaps also tracking back to Durkheim).

?Extension to other sectors of education. Bourdieu has written extensively on universities eg (Bourdieu and Collier 1988), but this work is begging to be

updated in light the perceived “crisis” in the higher education field.

?More scope for Bourdieuvian analysis using field theory– perhaps taking the lead from media studies in considering the boundaries between fields and

meta-capital.

?Questioning of the dark side of social capital in education – focus away from the “problems” of lack of social capital to the problems associated with too

much of it in the wrong hands. Related to this, the idea of sympathy – mutual

understanding (taking up Farr’s suggestion)

More investigation of institutional properties which help/hinder social capital. My interest: extending bourdieu’s work by looking at the interplay of cultural cap ital and social capital in the field of higher education, and the potential for HE to create links and openings to other fields –“bridging” rather than “bonding” social capital. This is where we return to the current day Lyda Hanifans seeking to remake education to serve social ends.

Balatti, J. and I. Falk (2001). Socioeconomic Contributions of Adult Learning to Community: A social capital perspective. Wider Benefits of Learning:

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Portugal, European Society for Research on the Education of Adults (ESREA). Baron, S., J. Field, et al. (2001). Social capital : critical perspectives. Oxford, Oxford University Press.

Barrett, R. (2004). "A review of Christopher Winch, 2000, Education, work and social capital: towards a new conception of vocational education, London:

Routledge." Studies in Philosophy and Education 23(23): 61-71.

Becker, G. S. (1964). Human capital; a theoretical and empirical analysis, with special reference to education. New York,, National Bureau of Economic Research;

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Russell Sage Foundation.

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Chicago, University of Chicago Press.

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Foley, M. W. and B. Edwards (1999). "Is it time to disinvest in social capital?"

Journal of Public Policy 19(2): 141 (33).

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双代号网络图六个参数的两种简易计算方法及实例分析

双代号网络图计算方法是每年建造师考试中的必考题，小到选择题、大到案例分析题，笔者在此总结2种计算方法，并附实例，供大家参考学习，互相交流，考出好成绩。 双代号网络图计算方法一 一、要点： 任何一个工作总时差≥自由时差 自由时差等于各时间间隔的最小值（这点对六时参数的计算非常用用） 关键线路上相邻工作的时间间隔为零，且自由时差=总时差 最迟开始时间—最早开始时间（最小） 关键工作：总时差最小的工作 最迟完成时间—最早完成时间（最小） 在网络计划中，计算工期是根据终点节点的最早完成时间的最大值 二、双代号网络图六时参数我总结的计算步骤（比书上简单得多） ①② t过程 做题次序： 1 4 5 ES LS TF 2 3 6 FS LF FF

步骤一： 1、A 上再做A 下 2 3、起点的A 上=0，下一个的A 上 A 上 4、A 下=A 上+t 过程（时间） 步骤二： 1、 B 下再做B 上 2、 做的方向从结束点往开始点 3、 结束点B 下=T （需要的总时间=结束工作节点中最大的A 下） 结束点B 上=T-t 过程（时间） 4、B 下=前一个的B 上（这里的前一个是从终点起算的） 遇到多指出去的时，取数值小的B 上 B 上=B 下—t 过程（时间） 步骤三： 总时差=B 上—A 上=B 下—A 下 如果不相等，你就是算错了 步骤四： 自由时差=紧后工作A 上（取最小的）—本工作A 下 =紧后工作的最早开始时间—本工作的最迟开始时间 （有多个紧后工作的取最小值） 例：

双代号网络图计算方法二 一、双代号网络图6个时间参数的计算方法（图上计算法） 从左向右累加，多个紧前取大，计算最早开始结束； 从右到左累减，多个紧后取小，计算最迟结束开始。 紧后左上-自己右下=自由时差。 上方之差或下方之差是总时差。 计算某工作总时差的简单方法：①找出关键线路，计算总工期； ②找出经过该工作的所有线路，求出最长的时间 ③该工作总时差=总工期-② 二、双代号时标网络图 双代号时标网络计划是以时间坐标为尺度编制的网络计划，以实

双代号网络图解析实例.doc

一、双代号网络图6个时间参数的计算方法（图上计算法） 从左向右累加，多个紧前取大，计算最早开始结束； 从右到左累减，多个紧后取小，计算最迟结束开始。 紧后左上-自己右下=自由时差。 上方之差或下方之差是总时差。 计算某工作总时差的简单方法：①找出关键线路，计算总工期； ②找出经过该工作的所有线路，求出最长的时间 ③该工作总时差=总工期-② 二、双代号时标网络图 双代号时标网络计划是以时间坐标为尺度编制的网络计划，以实箭线表示工作，以虚箭线 表示虚工作，以波形线表示工作的自由时差。 双代号时标网络图 1、关键线路 在时标双代号网络图上逆方向看，没有出现波形线的线路为关键线路（包括虚工作）。如图中①→②→⑥→⑧ 2、时差计算 1）自由时差 双代号时标网络图自由时差的计算很简单，就是该工作箭线上波形线的长度。 如A工作的FF=0，B工作的FF=1 但是有一种特殊情况，很容易忽略。

如上图，E工作的箭线上没有波形线，但是E工作与其紧后工作之间都有时间间隔，此时E工作 的自由时差=E与其紧后工作时间间隔的最小值，即E的自由时差为1。 2）总时差。 总时差的简单计算方法： 计算哪个工作的总时差，就以哪个工作为起点工作（一定要注意，即不是从头算，也不是 从该工作的紧后算，而是从该工作开始算），寻找通过该工作的所有线路，然后计算各条线路的 波形线的长度和，该工作的总时差=波形线长度和的最小值。 还是以上面的网络图为例，计算E工作的总时差： 以E工作为起点工作，通过E工作的线路有EH和EJ，两条线路的波形线的和都是2，所以此时E 的总时差就是2。 再比如，计算C工作的总时差：通过C工作的线路有三条，CEH，波形线的和为4；CEJ，波 形线的和为4；CGJ，波形线的和为1，那么C的总时差就是1。

双代号网络图时间参数的计算

双代号网络图时间参数的计算 二、工作计算法 【例题】：根据表中逻辑关系，绘制双代号网络图，并采用工作计算法计算各工作的时间参数。

紧前- A A B B、C C D、E E、F H、G 时间 3 3 3 8 5 4 4 2 2 （一）工作的最早开始时间ES i-j --各紧前工作全部完成后，本工作可能开始的最早时刻。

3 6 14 （二）工作的最早完成时间EF i-j EF i-j= ES i-j + D i-j 1 ?计算工期T c等于一个网络计划关键线路所花的时间，即网络计划结束工作最早完成时间的最大值，即T c = max {EF i-n} 2 .当网络计划未规定要求工期T r时，T p= T c 3 .当规定了要求工期T r时，T c

2. 其他工作的最迟完成时间按逆箭头相减，箭尾相碰取小值”计算。--在不影响计划工期的前提下，该工作最迟必须完成的时刻。 （四）工作最迟开始时间LS i-j LS i-j = LF i-j —D i-j --在不影响计划工期的前提下，该工作最迟必须开始的时刻。 （五）工作的总时差TF i-j TF i-j = LS i-j —ES i-j 或TF i-j = LF i-j —EF i-j --在不影响计划工期的前提下，该工作存在的机动时间。

FF i-j = ES j-k — EF i-j 作业1 :根据表中逻辑关系，绘制双代号网络图。 工作 A B C D E F 紧前 工作 - A A B B 、 C D 、E 3 6 6 0 6 — 1 \i 3 F G(4) I 上卩1 0 0 0 3 3 6 9 3 4 14 T L8 0 z o T 5： ：1116 5 6 12 6 16 T Lfl J6 5 n N 0 0 0 3 3 0 6 9 3 4 14 5 6卩2 戶 - G(4) ：1114 L8 0 1 !0 4 :n 眇s Lfl 1(2) 11(2) 11 ■ Hl N r T 7 B(3) D(8) 6 E(5) X （六）自由时差 FF i-j --在不影响紧后工作最早开始时间的前提下, 该工作存在的机动时间。 6 k> K) ■1114 J E(5) 6 5： S F(4) D(8) 3 6 7 6 9

双代号网络图六个参数计算方法(各实务专业通用)

寄语：不管一建、二建，双代号是必考点，再复杂的网络图也能简单化， 本工作室整理了 三页纸供大家快速掌握，希望大家多学多练，掌握该知识 点，至少十分收入囊中。 双代号网络图六个参数计算的简易方法 一、非常有用的要点： 任何一个工作总时差≥自由时差 自由时差等于各时间间隔的最小值（这点对六时参数的计算非常用用） 关键线路上相邻工作的时间间隔为零，且自由时差=总时差 最迟开始时间—最早开始时间（最小） 关键工作：总时差最小的工作 最迟完成时间—最早完成时间（最小） 在网络计划中，计算工期是根据终点节点的最早完成时间的最大值 二、双代号网络图六时参数我总结的计算步骤（比书上简单得多） ① ② t 过程 做题次序： 1 4 5 ES LS TF 2 3 6 FS LF FF 步骤一： 1、A 上再做 A 下 2、 做的方向从起始工作往结束工作方向； 3、 起点的 A 上=0，下一个的 A 上=前一个的 A 下当遇到多指向时，要取数值大的 A 下

A 上 4、 A 下=A 上+t 过程（时间） 步骤二： 1、 B 下再做 B 上 2、 做的方向从结束点往开始点 3、 结束点 B 下=T （需要的总时间结束点 B 上=T-t 过程（时间） 4、 B 下=前一个的 B 上（这里的前一个是从终点起算的） 遇到多指出去的时，取数值小的 B 上 B 上=B 下—t 过程（时间） 步骤三： 总时差=B 上—A 上=B 下—A 下 如果不相等，你就是算错了 步骤四： 自由时差=紧后工作 A 上（取最小的）—本工作 A 下 =紧后工作的最早开始时间—本工作的最迟开始时间 （有多个紧后工作的取最小值） 例：

双代号网络图最简单的计算方法

建筑工程双代号网络图是应用较为普遍的一种网络计划形式。它是以箭线及其两端节点的编号表示工作的网络图。 双代号网络图中的计算主要有六个时间参数： ES：最早开始时间，指各项工作紧前工作全部完成后，本工作最有可能开始的时刻； EF：最早完成时间，指各项紧前工作全部完成后，本工作有可能完成的最早时刻 LF：最迟完成时间，不影响整个网络计划工期完成的前提下，本工作的最迟完成时间； LS：最迟开始时间，指不影响整个网络计划工期完成的前提下，本工作最迟开始时间； TF：总时差，指不影响计划工期的前提下，本工作可以利用的机动时间； FF：自由时差，不影响紧后工作最早开始的前提下，本工作可以利用的机动时间。 双代号网络图时间参数的计算一般采用图上计算法。下面用例题进行讲解。 例题：试计算下面双代号网络图中，求工作C的总时差？ 早时间计算：ES，如果该工作与开始节点相连，最早开始时间为0，即A的最早开始时间ES=0；

EF，最早结束时间等于该工作的最早开始+持续时间，即A的最早结束EF为0+5=5； 如果工作有紧前工作的时候，最早开始等于紧前工作的最早结束取大值，即B的最早开始FS=5，同理最早结束EF为5+6=11，而E 工作的最早开始ES为B、C工作最早结束（11、8）取大值为11。 最迟完成时间计算：LF，从最后节点开始算起也就是自右向左。 如果该工作与结束节点相连，最迟完成时间为计算工期23，即F的最迟结束时间LF=23； 中间工作最迟完成时间等于紧后工作的最迟完成时间减去紧后工作的持续时间。如果工作有紧后工作，最迟完成时间等于紧后工作最迟开始时间取小值。 LS，最迟开始时间等于最迟结束时间减去持续时间，即LS=LF-D； 时差计算： FF，自由时差=（紧后工作的ES-本工作的EF）； TF，总时差=（紧后工作的LS-本工作的ES）或者=（紧后工作的LF-本工作的EF）。 该题解析： 则C工作的总时差为3.

双代号网络图的绘制技巧

双代号网络图的绘制技巧 双代号网络图又称网络计划技术或箭条图，简称网络图。在我国随着建筑领域投资包干和招标承包制的深入贯彻执行，在施工过程中对进度管理、工期管理和成本监督方面要求愈益严格，网络计划技术在这方面将成为有效的工具。借助电子计算机，从计划的编制、优化、到执行过程中调整和控制，网络计划技术突现出它的优势，越来越被人们广泛认识、了解和使用。 1 绘图中普遍存在的问题 常听说大家对网络图的绘制比较头疼。因为在绘图时，工序与工序之间的逻辑关系难以把握、什么地方需要架设虚工序看不出来、前边工序什么时候相交、如何为后行工序做准备、网络图开始如何绘制、结尾如何收口等一系列问题都是我们绘制网络图必须遇到的问题和步骤。 如果掌握绘制技巧就能快速准确地完成绘图要求。下面我把这几年自己总结出来一套有效的方法介绍给大家。 ２网络图的绘制技巧 2.１网络图的三大要素网络图是由节点、工序和线路三大要素构成的。

２.1.１节点 节点是用圆圈表示箭线之间的分离与交会的连接点。它由不同的代号来区，表示工序的结束与工序的开始的瞬间，具有承上启下的连接作用；它不占用时间，也不消耗资源。在网络图中结点分为开始结点、结束结点和中间结点三种。２.１.2 工序（工作） 工序是指把计划任务按实际需要的粗细程度划分成若干要消耗时间、资源、人力和材料的子项目。在网络图中用两个节点和一条箭线表示。箭线上方表示工序代号，下方表示工序作业时间。 2.１.３线路 线路是指在双代号网络图中从起点节点沿着箭线方向顺序通过一系列箭线和节点而达到终点节点的通道。一个完整的网路图有若干条线路组成，在诸多线路中作业时间相加最长的一条称为关键线路，宜用粗箭线、双箭线表示，使其一目了然。 2.２网络图的绘制技巧 要想快速准确地绘制双代号网路图，应先把工程项目的“工作明细表”分四步认真仔细的进行分析与研究。 ２.２.１网络图开头绘制技巧先从“工作明细表”中找出开始的工序。寻找的方法是：只要在“先行工序”一列中没有先行工序的工序，必定是开始的工序。这时候只需画一个

双代号网络图的绘制方法

双代号网络图的绘制方法 一、根据题目要求画出工作逻辑关系矩阵表，格式如下： 二、根据工作逻辑矩阵表计算工作位置代号表，为了使双代号网络图的条理清楚，各工作的布局合理，可以先按照下列原则确定各工作的开始节点位置号和结束节点位置号，然后按各自的节点位置号绘制网络图。

位置代号计算规则： ①无紧前工作的工作（即双代号网络图开始的第一项工作），其开始节点位置号为零； ②有紧前工作的工作，其开始节点位置号等于其紧前工作的开始节点位置号的最大值加1； ③有紧后工作的工作，其结束节点位置号等于其紧后工作的开始节点位置号的最小值； ④无紧后工作的工作（即双代号网络图开始的最后一项工作），其结束节点位置号等于网络图中各工作的结束节点位置号的最大值加1。 三、绘制双代号网络进度计划表，按照下列绘图原则： 1、绘制没有紧前工作的工作箭线，使他们具有相同的开始节点，以保证网络图只有一个起点节点。 2、依次绘制其他工作箭线。这些工作箭线的绘制条件是其所有紧前工作箭线都已经绘制出来。在绘制这些工作箭线时，应按下列原则进行： ①当所要绘制的工作只有一项紧前工作时，则将该工作箭线直接绘制在其紧前工作之后即可。 ②当所要绘制的工作只有多项紧前工作时，应按以下四种情况分别予以考虑：

第一种情况：对于所要绘制的工作而言，如果在其多项紧前工作中存 在一项（且只存在一项）只作为本工作紧前工作的工作（即在紧前工作栏中，该紧前工作只出现一次），则应将本工作箭线直接画在该紧前工作箭 线之后，然后用虚箭线将其他紧前工作箭线的箭头节点与本工作的箭尾节 点分别相连，以表达它们之间的逻辑关系。 第二种情况：对于所要绘制的工作而言，如果在其紧前工作中存在多项只作为本工作紧前工作的工作，应将这些紧前工作的箭线的箭头节点合并，再从合并之后节点开始，画出本工作箭线，然后用虚箭线将其他紧前工作箭线的箭头节点与本工作的箭尾节点分别相连，以表达它们之间的逻辑关系。 第三种情况：对于所要绘制的工作而言，如果不存在第一和第二种情况时，应判断本工作的所有紧前工作是否都同时是其他工作的紧前工作（即在紧前工作栏中，这几项紧前工作是否均同时出现若干次）。如果上述条件成立，应将这些紧前工作的箭线的箭头节点合并，再从合并之后节点开始，画出本工作箭线。 第四种情况：对于所要绘制的工作而言，如果不存在第一和第二种情况，也不存在第三种情况时，则应将本工作箭线单独划在其紧前工作箭线之后的中部，然后用虚箭线将其他紧前工作箭线的箭头节点与本工作的箭尾节点分别相连，以表达它们之间的逻辑关系。 3、当各项工作箭线都绘制出来以后，应合并那些没有紧后工作的工作箭线的箭头节点，以保证网络图只有一个终点节点。

双代号网络图计算(新)

概念部分 双代号网络图是应用较为普遍的一种网络计划形式。它是以箭线及其两端节点的编号表示工作的网络图，如图12-l所示。 图12-1 双代号网络图 双代号网络图中，每一条箭线应表示一项工作。箭线的箭尾节点表示该工作的开始，箭线的箭头节点表示该工作的结束。 工作是指计划任务按需要粗细程度划分而成的、消耗时间或同时也消耗资源的一个子项目或子任务。根据计划编制的粗细不同，工作既可以是一个建设项目、一个单项工程，也可以是一个分项工程乃至一个工序。 一般情况下，工作需要消耗时间和资源（如支模板、浇筑混凝土等），有的则仅是消耗时间而不消耗资源（如混凝土养护、抹灰干燥等技术间歇）。在双代号网络图中，有一种既不消耗时间也不消耗资源的工作——虚工作，它用虚箭线来表示，用以反映一些工作与另外一些工作之间的逻辑关系，如图12-2所示，其中2-3工作即为虚工作。 图12-2 虚工作表示法 节点是指表示工作的开始、结束或连接关系的圆圈（或其他形状的封密图形）、箭线的出发节点叫作工作的起点节点，箭头指向的节点叫作工作的终点节点。任何工作都可以用其箭线前、后的两个节点的编码来表示，起点节点编码在前，终点节点编码在后。 网络图中从起点节点开始，沿箭头方向顺序通过一系列箭线与节点，最后达到终点节点的通路称为线路。一条线路上的各项工作所持续时间的累加之和称为该线路之长，它表示完成该线路上的所有工作需花费的时间。理论部分： 一节点的时间参数 1．节点最早时间 节点最早时间计算一般从起始节点开始，顺着箭线方向依次逐项进行。 （1）起始节点 起始节点i如未规定最早时间ET i时，其值应等于零，即 （12-1） 式中——节点i的最早时间； （2）其他节点

双代号网络图计算最简便方法

双代号网络图参数计算简易方法 一、非常有用的要点： 任何一个工作的总时差≥自由时差； 自由时差等于各时间间隔的最小值（这点对六时参数的计算非常用用）； 关键线路上相邻工作的时间间隔为零，且自由时差=总时差； 最迟开始时间—最早开始时间（最小） 关键工作：总时差最小的工作 最迟完成时间—最早完成时间（最小） 在网络计划中，计算工期是根据终点节点的最早完成时间的最大值。 二、双代号网络图六时参数的计算步骤（比书上简单得多） 最早开始ES 最迟开始LS 总时差TF 最早完成EF 最迟完成LF 自由时差FF 做题次序： 1 4 5 2 3 6 先求最早开始，再求最早完成，然后求最迟完成，第4步求最迟开始，第5步求总时差，第6步求自由时差。

步骤一： 1、先求最早开始，然后求最早完成； 2、做题方向：从起始工作往结束工作方向； 3、起点的最早开始= 0，下一个的最早开始=前一个的最早完成；当遇到多指向时，取数值大的最早完成。 最早完成=最早开始+持续时间 步骤二： 1、先求最迟完成，然后求最迟开始； 2、做题方向：从结束工作往开始工作方向； 3、结束点的最迟完成=工期T，（需要的总时间=结束工作节点中最大的最迟完成）， 结束点的最迟开始=工期T－持续时间； 4、最迟完成=前一个的最迟开始（这里的前一个是从终点起算的）；遇到多指向的时候，取数值小的最迟开始； 最迟开始=最迟完成－持续时间 步骤三： 总时差=最迟开始－最早开始=最迟完成－最早完成；如果不相等，你就是算错了； 步骤四： 自由时差=紧后工作最早开始(取最小的)－最早完成。

例： 总结起来四句话： 1、最早开始时间从起点开始，最早开始=紧前最早结束的max值； 2、最迟完成时间从终点开始，最迟完成=紧后最迟开始的min值； 3、总时差=最迟－最早； 4、自由时差=紧后最早开始的min值－最早完成。 注：总时差=自由时差＋紧后总时差的min值。

双代号网络计划图计算方法简述

一、一般双代号网络图（没有时标）6个时间参数的计算方法（图上计算法） 6时间参数示意图： （左上）最早开始时间 | （右上）最迟开始时间 | 总时差 （左下）最早完成时间 | （右下）最迟完成时间 | 自由时差 计算步骤： 1、先计算“最早开始时间”和“最早完成时间”（口诀：早开加持续）： 计算方法：起始工作默认“0”为“最早开始时间”，然后从左向右累加工作持续时间，有多个紧前工作的取大值。 2、再计算“最迟开始时间”和“最迟完成时间”（口诀：迟完减持续）： 计算方法：结束工作默认“总工期”为“最迟完成时间”，然后从右到左累减工作持续时间，有多个紧后工作取小值。（一定要注意紧前工作和紧后工作的个数） 3、计算自由时差（口诀：后工作早开减本工作早完）： 计算方法：紧后工作左上（多个取小）-自己左下=自由时差。 4、计算总时差（口诀：迟开减早开或迟完减早完）： 计算方法：右上-左上=右下-左下=总时差。 计算某工作总时差的简单方法：①找出关键线路，计算总工期； ②找出经过该工作的所有线路，求出最长的时间 ③该工作总时差=总工期-② 二、双代号时标网络图（有时标，计算简便） 双代号时标网络计划是以时间坐标为尺度编制的网络计划，以实箭线表示工作，以虚箭线表示虚工作（虚工作没有持续时间，只表示工作之间的逻辑关系，即前一个工作完成后一个工作才能开始），以波形线表示该工作的自由时差。（图中所有时标单位均表示相应的持续时间，另外虚线和波形线要区分） 示例：双代号时标网络图 1、关键线路 在时标双代号网络图上逆方向看，没有出现波形线的线路为关键线路（包括虚工作）。如图中①→②→⑥→⑧

双代号网络计划图计算方法口诀简述

般双代号网络图（没有时标）6个时间参数的计算方法（图上计算法） 6时间参数示意图: （左上）最早开始时间| （右上）最迟开始时间| 总时差 （左下）最早完成时间| （右下）最迟完成时间| 自由时差 计算步骤： 1、先计算“最早开始时间”和“最早完成时间” （口诀：早开加持续）： 计算方法：起始工作默认“ 0”为“最早开始时间”，然后从左向右累加工作持续时间，有多个紧前工作的取大值。 2、再计算“最迟开始时间”和“最迟完成时间” （口诀：迟完减持续）： 计算方法：结束工作默认“总工期”为“最迟完成时间”，然后从右到左累减工作 持续时间，有多个紧后工作取小值。（一定要注意紧前工作和紧后工作的个数） 3、计算自由时差（口诀：后工作早开减本工作早完）： 计算方法：紧后工作左上（多个取小）-自己左下=自由时差。 4、计算总时差（口诀：迟开减早开或迟完减早完）： 计算方法：右上-左上二右下-左下二总时差。 计算某工作总时差的简单方法：①找出关键线路，计算总工期; ②找出经过该工作的所有线路，求出最长的时间 ③该工作总时差=总工期-② 二、双代号时标网络图（有时标，计算简便） 双代号时标网络计划是以时间坐标为尺度编制的网络计划，以实箭线表示工作，以虚箭线表示虚工作（虚工作没有持续时间，只表示工作之间的逻辑关系，即前一个工作完成后一个工作才能开始），以波形线表示该工作的自由时差。（图中所有时标单位均表示相应的持续时间，另外虚线和波形线要区分） 示例：双代号时标网络图 双代号吋标网络图 1、关键线路 在时标双代号网络图上逆方向看，没有出现波形线的线路为关键线路（包括虚工作）如图中①一②一⑥一⑧ 2时差计算（这里只说自由时差和总时差，其余4个时差参见前面的累加和累减）1）自由

双代号网络图参数计算的简易方法(优选.)

最新文件---------------- 仅供参考--------------------已改成-----------word文本 --------------------- 方便更改 赠人玫瑰，手留余香。 双代号网络图参数计算的简易方法 一、非常有用的要点： 任何一个工作总时差≥自由时差 自由时差等于各时间间隔的最小值（这点对六时参数的计算非常用用） 关键线路上相邻工作的时间间隔为零，且自由时差=总时差 最迟开始时间—最早开始时间（最小） 关键工作：总时差最小的工作 最迟完成时间—最早完成时间（最小） 在网络计划中，计算工期是根据终点节点的最早完成时间的最大值。 二、双代号网络图六时参数总结的计算步骤（比书上简单得多） 最早开始时间ES 最迟开始时间LS 总时差 最早完成时间EF 最迟完成时间LF 自由时差

简记为： A 上 B 上 总时差 A下 B下自由时差 ①② t过程 做题次序： 1 4 5 2 3 6 步骤一： 1、A上再做A下 2、的方向从起始工作往结束工作方向； 3、起点的A上=0，下一个的A上=前一个的A下； 当遇到多指向时，要取数值大的A 下

A上 4、A下=A上+t过程（时间） 步骤二： 1、B下再做B上 2、做的方向从结束点往开始点 3、结束点B下=T（需要的总时间=结束工作节点中最大的A下） 结束点B 上= T-t过程（时间） 4、B下=前一个的B上（这里的前一个是从终点起算的） 遇到多指出去的时，取数值小的B上 B下 t过程（时间） B上=B下—t过程（时间） 步骤三： 总时差=B 上—A 上 =B 下 —A 下

如果不相等，你就是算错了步骤四： 自由时差=紧后工作A 上（取最小的）—本工作A 下 例： 6 8 2 * 9 11 2

双代号网络图时间参数计算技巧

双代号网络图作为工程项目进度管理中，是最常用的工作进度安排方法，也是工程注册类执业考试中必考内容，对它的掌握程度，决定了实务考试的通过概率大小。 双代号网络图时间参数主要为6个时间参数（最早开始时间、最早完成时间、最迟开始时间、最迟完成时间、总时差和自由时差）的计算，按计算方法可以分为： 1、节点计算法 2、工作计算法 3、表格计算法 节点计算法最适合初学者，其计算方法简单、快速。 计算案例： 某工程项目的双代号网络见下图。（时间单位：月） [问题] 计算时间参数和判断关键线路。 [解答] 1、计算时间参数 （1）计算节点最早时间，计算方法：最早时间：从左向右累加，取最大值。

（2）计算最迟时间, 最迟时间计算方法：从右向左递减，取小值。 2、计算工作的六个时间参数 自由时差：该工作在不影响其紧后工作最早开始时间的情况下所具有的机动时间。 总时差：该工作在不影响总工期情况下所具有的机动时间。 通过前面计算节点的最早和最迟时间，可以先确定工作的最早开始时间和最迟完成时间，根据工作持续时间，计算出最早完成时间和最迟开始时间，以F工作为例，计算F工作的4个参数（以工作计算法标示）如下：

注:EF=ES+工作持续时间 LF=LS+工作持续时间 接下来计算F工作的总时差TF，在工作计算法中，总时差TF=LS-ES或LF-EF，在节点计算法，总时差TF可以紧后工作的最迟时间-本工作的最早完成时间，或者是紧后工作最迟时间-最早时间，以F工作为例计算它的TF： 接下来计算F工作的自由时差FF，根据定义：该工作在不影响其紧后工作最早开始时间的情况下所具有的机动时间，自由时差FF=紧后工作最早（或最小）开始时间-本工作最早完成时间ES，以F工作为例，F的紧后工作为G和H，G工作的最早开始时间为10（即4节点的最早时间），H工作的最早开始时间为11（即5节点的最早时间），G工作的时间最小，所以F的自由时差FF=G工作的最早开始时间ES-F工作的最早完成时间EF：

双代号网络图解析实例

一、双代号网络图6个时间参数的计算方法（图上计算法）从左向右累加，多个紧前取大，计 算最早开始结束；从右到左累减，多个紧后取小，计算最迟结束开始。 紧后左上-自己右下=自由时差。上方之差或下方之差是总时差。 计算某工作总时差的简单方法：①找出关键线路，计算总工期； ②找出经过该工作的所有线路，求出最长的时间 ③该工作总时差=总工期-② 二、双代号时标网络图双代号时标网络计划是以时间坐标为尺度 编制的网络计划，以实箭线表示工作，以虚箭线 表示虚工作，以波形线表示工作的自由时差。 双代号时标网络图 1、关键线路 在时标双代号网络图上逆方向看，没有出现波形线的线路为关键线路（包括虚工作）如图中①一②一⑥一⑧ 2、时差计算1）自由时差 双代号时标网络图自由时差的计算很简单，就是该工作箭线上波形线的长度。 如A工作的FF=O, B工作的FF=1 但是有一种特殊情况，很容易忽略。

如上图，E工作的箭线上没有波形线，但是E工作与其紧后工作之间都有时间间隔，此时E X作的自由时差=E与其紧后工作时间间隔的最小值，即E的自由时差为1。 2）总时差。 总时差的简单计算方法： 计算哪个工作的总时差，就以哪个工作为起点工作（一定要注意，即不是从头算，也不 是 从该工作的紧后算，而是从该工作开始算），寻找通过该工作的所有线路，然后计算各 条线路的 波形线的长度和，该工作的总时差=波形线长度和的最小值。 还是以上面的网络图为例，计算E工作的总时差： 以E工作为起点工作，通过E工作的线路有EH ffi EJ,两条线路的波形线的和都是2,所以此时E 的总时差就是2。 再比如，计算C工作的总时差：通过C工作的线路有三条，CEH波形线的和为4; CEJ 波形线的和为4；CGJ波形线的和为1,那么C的总时差就是1