什么是项目管理中的龙卷风图？

Project managers should not ignore the uncertainty; instead, they should analyze and understand them better as part ofrisk management进行强大的决策过程。

在初始阶段，由于信息的可用性有限，不确定性很高。但是，随着项目的进行，情况变得清晰，项目计划通过渐进式阐述.

预测在项目计划中起着关键作用，龙卷风图有助于提高项目预测的信心水平。

龙卷风图是确定预测置信度的简单工具。这种预测技术使您可以可视化不确定性的影响，例如一个变量的变化如何影响输出变量。

结果从最大到最小的分类。由于资源有限，项目无法应对所有风险。b0b体育app因此，您将它们对其进行排名，并将资源集中在解决具有重大影响的变b0b体育app量上。

什么是龙卷风图？

A tornado diagram is a risk mapping tool similar to a bar chart. It helps carry out sensitivity analysis for comparing the relative importance of variables.

Since the shape of this chart looks like a tornado, this diagram is known as a tornado diagram.

A tornado diagram is a sensitivity analysis tool that allows you to study how uncertainty in the output of a mathematical model can be distributed among input variables. Other sensitivity analysis tools include spider diagrams, correlations, critical indexes, probability Gantt charts, and schedule impact indicators.

A project has many variables, and you must know the impact of a variable on the outcome. The concerned outcome can be cost, project duration, or quality. You should know how sensitive the output is to a particular variable and know how to prioritize it.

To analyze the impact of a value, only one input variable is considered at a time while keeping others at the baseline.

绘制图表后，您可以看到哪个变量对结果具有最大的影响。您可以审查的一些结果包括经济指数，例如内部收益率（IRR），净现值（NPV），雇用资本回报率（ROCE）和净现金回报（NCR）。

How to Create a Tornado Diagram

步骤1：制定模型

Here, you use a deterministic model, i.e., a formula against a statistical one called stochastic. Project models can be economical, schedule, quality, cost, etc.

For example, you may want to analyze a high NPV or IRR project, schedule, etc.

These desired outcomes depend on several variables. Therefore, you will need to analyze them individually to find which variable affects the outcome most.

这有助于制定缓解计划。

Step 2: Assess the Range

对于每个变量，分配一个合理的值范围。示例包括：

最糟糕的情况 - 最低价值/缺点

基本案例 - 基线价值/很可能

最佳/乐观的情况 - 最高价值/上升空间

该范围应适度建议+/- 10％。

变量不应超过范围集。在这里，经验和专家判断有助于设定适当的最差案例，最佳基准和基线价值。

步骤3：选择值度量

选择选定结果的值度量。假设NPV，为此插图。

步骤4：计算值度量的范围

This is the highest and lowest value.

Here, you tweak one variable while keeping other variables at baseline and examine the impact on the NPV. Record the outcomes for upside and downside, and then tabulate.

您将研究三个输入变量的典型情况是汇率，资本支出和销量。

注意,这些输入的不确定性,和你are examining which fluctuations (uncertainty) will influence the NPV most.

Step 5: Plot the Tornado Chart

Using MS Excel, plot the bar chart for the upside and downside, then rank it; it will look like a tornado.

The diagram shows how sensitive the NPV is to each variable. You can see that the exchange rate is the most impactful variable. You can now develop a risk response plan to manage this variable.

Relationship between Tornado Diagram, Monte Carlo Simulation, and Decision Tree

These are all diagrammatic decision-making tools; however, tornado diagrams consider the effect of one variable on the output and do not involve probability.蒙特卡洛模拟and Decision Tree use probabilistic distribution or stochastic approach.

龙卷风图的好处

• 它有助于优化资源利用率。
• 它可以帮助您找到每个变量的相对重要性。
• A quick view shows you the most impacting variable.

Limitations of Tornado Diagram

• 它一次处理一个变量，因为这些变量是互连的，因此可能与实际情况不符。单独研究时，变量的行为可能会有所不同。

概括

A tornado diagram is a great tool for analyzing the impact of a variable on the desired outcome. Project managers can study it, make better decisions, and invest resources in variables that matter most.