管理高手的特点是，总在寻找三个东西：线索、快乐、可能性。
　　
　寻找线索，从寻找线索开始，边干边琢磨，静下心找寻事物的本质规律。实事求是，避免武断，智商高。
　寻找快乐，黑暗处找光明，口吐鲜花，具建设性，情商高。
　寻找可能性，在没有试过所有的可能性之前，不轻易放弃，逆商高。
　　
　遇到问题，管理高手不是在会议室里夸夸其谈，而是下基层去和机器谈、和操作工人谈、和记录谈，通过线索找出问题的症结所在。
　在开会时，那些为了安定团结而和稀泥的、为他人打气的、大谈前景的、寻找同乐共赢的，是管理高手；只谈问题的、对别人的错误纠缠不休的，是低手。
　不断地尝试可能性，懂得如时应该放弃的，是高手；一遇挫折就想放弃，或者死钻牛角尖，或者一再重复错误的，是低手

Complex projects require a series of activities, some of which must be performed sequentially and others that can be performed in parallel with other activities.
This collection of series and parallel tasks can be modeled as a network.
In 1957 the Critical Path Method (CPM) was developed as a network model for project management. CPM is a deterministic method that uses a fixed time estimate for each activity. While CPM is easy to understand and use, it does not consider the time variations that can have a great impact on the completion time of a complex project.
The Program Evaluation and Review Technique (PERT) is a network model that allows for randomness in activity completion times. PERT was developed in the late 1950's for the U.S. Navy's Polaris project having thousands of contractors.
It has the potential to reduce both the time and cost required to complete a project.
The Network Diagram In a project, an activity is a task that must be performed and an event is a milestone marking the completion of one or more activities. Before an activity can begin, all of its predecessor activities must be completed. Project network models represent activities and milestones by arcs and nodes. PERT originally was an activity on arc network, in which the activities are represented on the lines and milestones on the nodes. Over time, some people began to use PERT as an activity on node network. For this discussion, we will use the original form of activity on arc.
The PERT chart may have multiple pages with many sub-tasks. The following is a very simple example of a PERT diagram:
PERT Chart

The milestones generally are numbered so that the ending node of an activity has a higher number than the beginning node. Incrementing the numbers by 10 allows for new ones to be inserted without odifying the numbering of the entire diagram. The activities in the above diagram are labeled with letters along with the expected time required to complete the activity.
Steps in the PERT Planning Process
PERT planning involves the following steps:
Identify the specific activities and milestones.
Determine the proper sequence of the activities.
Construct a network diagram.
Estimate the time required for each activity.
Determine the critical path.
Update the PERT chart as the project progresses.
1. Identify Activities and Milestones
The activities are the tasks required to complete the project. The milestones are the events marking the beginning and end of one or more activities. It is helpful to list the tasks in a table that in later steps can be expanded to include information on sequence and duration.
2. Determine Activity Sequence
This step may be combined with the activity identification step since the activity sequence is evident for some tasks. Other tasks may require more analysis to determine the exact order in which they must be performed.
3. Construct the Network Diagram
Using the activity sequence information, a network diagram can be drawn showing the sequence of the serial and parallel activities. For the original activity-on-arc model, the activities are depicted by arrowed lines and milestones are depicted by circles or "bubbles".
If done manually, several drafts may be required to correctly portray the relationships among activities. Software packages simplify this step by automatically converting tabular activity information into a network diagram.
4. Estimate Activity Times
Weeks are a commonly used unit of time for activity completion, but any consistent unit of time can be used.
A distinguishing feature of PERT is its ability to deal with uncertainty in activity completion times. For each activity, the model usually includes three time estimates:
Optimistic time - generally the shortest time in which the activity can be completed. It is common practice to specify optimistic times to be three standard deviations from the mean so that there is approximately a 1% chance that the activity will be completed within the optimistic time.
Most likely time - the completion time having the highest probability. Note that this time is different from the expected time.
Pessimistic time - the longest time that an activity might require. Three standard deviations from the mean is commonly used for the pessimistic time.
PERT assumes a beta probability distribution for the time estimates. For a beta distribution, the expected time for each activity can be approximated using the following weighted average:
Expected time = ( Optimistic + 4 x Most likely + Pessimistic ) / 6
This expected time may be displayed on the network diagram.
To calculate the variance for each activity completion time, if three standard deviation times were selected for the optimistic and pessimistic times, then there are six standard deviations between them, so the variance is given by:
[ ( Pessimistic - Optimistic ) / 6 ]2
5. Determine the Critical Path
The critical path is determined by adding the times for the activities in each sequence and determining the longest path in the project. The critical path determines the total calendar time required for the project. If activities outside the critical path speed up or slow down (within limits), the total project time does not change. The amount of time that a non-critical path activity can be delayed without delaying the project is referred to as slack time.
If the critical path is not immediately obvious, it may be helpful to determine the following four quantities for each activity:
ES - Earliest Start time
EF - Earliest Finish time
LS - Latest Start time
LF - Latest Finish time
These times are calculated using the expected time for the relevant activities.
The earliest start and finish times of each activity are determined by working forward through the network and determining the earliest time at which an activity can start and finish considering its predecessor activities. The latest start and finish times are the latest times that an activity can start and
finish without delaying the project. LS and LF are found by working backward through the network. The difference in the latest and earliest finish of each activity is that activity's slack. The critical path then is the path through the network in which none of the activities have slack.
The variance in the project completion time can be calculated by summing the variances in the completion times of the activities in the critical path. Given this variance, one can calculate the probability that the project will be completed by a certain date assuming a normal probability distribution for the critical path. The normal distribution assumption holds if the number of activities in the path is large enough for the central limit theorem to be applied.
Since the critical path determines the completion date of the project, the project can be accelerated by adding the resources required to decrease the time for the activities in the critical path. Such a shortening of the project sometimes is referred to as project crashing.
6. Update as Project Progresses
Make adjustments in the PERT chart as the project progresses. As the project unfolds, the estimated times can be replaced with actual times. In cases where there are delays, additional resources may be needed to stay on schedule and the PERT chart may be modified to reflect the new situation.

Benefits of PERT
PERT is useful because it provides the following information:
Expected project completion time.
Probability of completion before a specified date.
The critical path activities that directly impact the completion time.
The activities that have slack time and that can lend resources to critical path activities.
Activity start and end dates.

Limitations
The following are some of PERT's weaknesses:
The activity time estimates are somewhat subjective and depend on judgement.
In cases where there is little experience in performing an activity, the numbers may be only a guess. In other cases, if the person or group performing the activity estimates the time there may be bias in the estimate.
Even if the activity times are well-estimated, PERT assumes a beta distribution for these time estimates, but the actual distribution may be different.
Even if the beta distribution assumption holds, PERT assumes that the probability distribution of the project completion time is the same as the that of the critical path. Because other paths can become the critical path if their associated activities are delayed, PERT consistently underestimates the expected project completion time.
The underestimation of the project completion time due to alternate paths becoming critical is perhaps the most serious of these issues. To overcome this limitation, Monte Carlo simulations can be performed on the network to eliminate this optimistic bias in the expected project completion time.

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过去,我们在项目管理过程中,对项目的成功有过许多的定义,一般来讲:项目成功意味着在一定的时间,成本,绩效情况下,完成项目的活动.在前几年,我们又对项目的成功增加了一个纬度,即:顾客满意度.我在自己的博客中对项目成功的四个纬度做了一定的阐述.

今天,我们认为项目成功已经不能局限于四个纬度的衡量了,我们认为:项目成功,特别是在企业考评项目成功的标准上面,需要增加三个条件:一是控制好项目的范围变化;二是不影响企业的管理流程;三是不改变企业的管理文化.

我们通过项目管理可以知道:几乎很少有项目是在原有的项目范围之内完成的,也就是说,项目的范围变化是不可避免的,关键是能否控制好项目的范围变化.项目的范围控制不是乞求项目的范围不变化或者较少变化,而是在项目范围如果必须要发生变化时,如何与业主达成共识!这一点至关重要.工程项目管理过程中,经常发生项目时间,成本,绩效在定量的条件下没有问题,问题就是出在项目的范围控制上面.

我们可能有这样的感觉,许多项目经理在完成了一个或者两个成功的项目之后,常常把自己看作是独立的"王国",喜欢将自己从企业中分离出来,期望将自己名片上的项目经理换成分公司的经理,感觉项目管理成功的趋向就是逐渐独立,这一点对实施项目管理是比较致命的打击,一个企业能否在项目管理上面取得长远的成功,关键是如何控制这些感觉有点飘飘然的家伙,评价一个项目的成功,要注重检查项目的管理是否仍然在公司的方针,政策,程序,规章和指导的方向下进行!

同样,评价项目的成功,还需要检查项目的文化是否融入公司的整体文化范围之中.我在检查自己公司的一些项目发现:一些感觉良好的项目经理,喜欢搞一些游离于企业文化之外的东西,这就无法保证其对公司的忠诚度,在某种程度上来讲:这与项目经理如何正确认识企业的发展与项目发展的长远关系.

二八定律：把时间花在最重要的事情上，可以化忙为闲      管理学中有一个重要的定律——“二八定律”，大意是，在任何特定群体中，重要的因子通常只约占20%，而不重要的因子约占80%，因此，只要能控制20%的重要因子，就能控制住全局。如果我们能够找出最重要的事情，将时间花在最重要的20%的事情上，而不是花在80%琐碎的事情上，自然可以化忙为闲。

时间管理四象限定律：按重要和紧迫的程度，确立做事顺序     还有一个“时间管理四象限”定律。它告诉我们：我们面临的工作任务有两个维度，一个是重要性维度，一个是紧迫性维度。这两个维度的地位是不同的，重要性是第一维度，紧迫性是第二维度，也就是说，重要性比紧迫性重要。当面临众多的工作任务时，正确的做事顺序是：首先，做“重要且紧迫”的事情；然后，做“重要但不紧迫”的事情；接下来，做“不重要但紧迫”的事情；最后，做“不重要也不紧迫”的事情。我们安排自己的各种活动时，不妨运用一下“时间管理四象限”定律。比如，和家人共度温馨时光是非常重要的事情，怎么来安排呢？把和家人共处这个事情安排在必须做的事情里，如果这个活动日程是以周或者月为单位的，那么你就会发现，再忙自己也有时间来完成它。

“马赛克”时间块定律：把握每件事之间的工作间隙，可偷得几分钟的闲 在紧张的工作日，又如何给自己留出休息的空隙呢？我们可以把每一个工作日看做是由大量10来分钟的小时间单元拼嵌而成的，姑且把这些时间小单元叫做“马赛克”时间块吧。当你做好了一件事情，在接着干另一件事之前，注意留出10来分钟的“马赛克”时间块，休息放松。如果你能灵活机敏地考虑你的时间安排，一天就能拿出许多个放松身心的“马赛克”时间块。

候鸟定律：依托团队，善于授权于他人 要忙里偷闲，还有一个重要的“候鸟定律”别忘了。你观察过群徙的候鸟吧，有没有发现它们是以“V”字形起飞的？据生物学家研究，这是候鸟合理地利用团队的力量，减低气流冲撞造成的压力。而这种团队飞行，要比单独飞行远72%以上。所以，当面临众多的工作任务时，你也不要试图一个人就把所有工作都承担下来，应该问问自己：工作中哪些事是可以授权他人去做的？