[转帖]项目管理常用分析方法汇集三

翔羽

网络计划技术： <a href="http://col.njtu.edu.cn/zskj/3012/wwwroot426/JC/chap14/010100.htm">http://col.njtu.edu.cn/zskj/3012/wwwroot426/JC/chap14/010100.htm</a><a href="http://col.njtu.edu.cn/zskj/3012/wwwroot426/JC/chap14/020400.htm"></a> KNZaetje.pdf (150.25 KB, 下载次数: 12)

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[转帖]项目管理常用分析方法汇集三

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翔羽

<strong><font color="#000000">决策树</font></strong><p class="MsoNormal" style="LAYOUT-GRID-MODE: char; TEXT-INDENT: 33pt; LINE-HEIGHT: 15pt;"><font color="#000000"><span style="FONT-FAMILY: 宋体;">有时我们会碰到这样的情况，一个决策方案对应几个相互排斥的可能状态，每一种状态都以一定的可能性（概率</span><span lang="EN-US">0-1</span><span style="FONT-FAMILY: 宋体;">）出现，并对应特定结果，这时的决策就被称为风险型决策。风险型决策的目的是如何使收益期望值最大，或者损失期望值最小。期望值是一种方案的损益值与相应概率的乘积之和。下面我们用决策树来说明风险型决策方法。</span></font></p><p class="MsoNormal" style="LAYOUT-GRID-MODE: char; TEXT-INDENT: 33pt; LINE-HEIGHT: 15pt;"><span style="FONT-FAMILY: 宋体;"><font color="#000000">决策树就是用数枝分叉形态表示各种方案的期望值，剪掉期望值小的方案枝，剩下的最后的方案即是最佳方案。<span style="COLOR: red;">决策树由决策结点、方案枝、状态结点、概率枝</span>四个要素组成。</font></span></p><p class="MsoNormal" style="LAYOUT-GRID-MODE: char; TEXT-INDENT: 33pt; LINE-HEIGHT: 15pt;"><font color="#000000"><span style="FONT-FAMILY: 宋体;">例如：某企业在下年度有甲、乙两种产品方案可供选择，每种方案都面临滞销、一般和畅销三种市场状态，各种状态的概率和损益值如下表所示：</span><span lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span></font></p><table class="MsoNormalTable" cellspacing="0" cellpadding="0" border="1" style="BORDER-RIGHT: medium none; BORDER-TOP: medium none; MARGIN-LEFT: 18.65pt; BORDER-LEFT: medium none; BORDER-BOTTOM: medium none; BORDER-COLLAPSE: collapse;"><tbody><tr style="HEIGHT: 40pt;"><td width="169" rowspan="2" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 1.5pt solid; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: windowtext 1.5pt solid; WIDTH: 126.8pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 40pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><line id="_x0000_s1025" to="126.75pt,39.75pt" from="-5.25pt,-2.25pt" style="Z-INDEX: 1; LEFT: 0px; POSITION: absolute; TOP: 0px; TEXT-ALIGN: left;"><font color="#000000"></font></line><line id="_x0000_s1026" to="126.75pt,108pt" from="-5.25pt,-1.5pt" style="Z-INDEX: 2; LEFT: 0px; POSITION: absolute; TOP: 0px; TEXT-ALIGN: left;"><font color="#000000"></font></line><line id="_x0000_s1027" to="42.75pt,110.25pt" from="-5.25pt,6pt" style="Z-INDEX: 3; LEFT: 0px; POSITION: absolute; TOP: 0px; TEXT-ALIGN: left;"><font color="#000000"></font></line><font color="#000000"><span lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span><span style="FONT-FAMILY: 宋体;">市场状态</span></font></p><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><font color="#000000"><span lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span><span style="FONT-FAMILY: 宋体;">概率</span></font></p><p class="MsoNormal" style="TEXT-INDENT: 20.9pt; LINE-HEIGHT: 15pt;"><span style="FONT-FAMILY: 宋体;"><font color="#000000">损益值</font></span></p><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span style="FONT-FAMILY: 宋体;"><font color="#000000">方案</font></span></p></td><td width="107" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 1.5pt solid; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 80.2pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 40pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span style="FONT-FAMILY: 宋体;"><font color="#000000">滞销</font></span></p></td><td width="108" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 1.5pt solid; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 81pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 40pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span style="FONT-FAMILY: 宋体;"><font color="#000000">一般</font></span></p></td><td width="120" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 1.5pt solid; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 90pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 40pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span style="FONT-FAMILY: 宋体;"><font color="#000000">畅销</font></span></p></td></tr><tr style="HEIGHT: 65.7pt;"><td width="107" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 80.2pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 65.7pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span lang="EN-US"><font color="#000000">0.2</font></span></p></td><td width="108" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 81pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 65.7pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span lang="EN-US"><font color="#000000">0.3</font></span></p></td><td width="120" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 90pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 65.7pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span lang="EN-US"><font color="#000000">0.5</font></span></p></td></tr><tr style="HEIGHT: 27.6pt;"><td width="169" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: windowtext 1.5pt solid; WIDTH: 126.8pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 27.6pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span style="FONT-FAMILY: 宋体;"><font color="#000000">甲方案</font></span></p></td><td width="107" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 80.2pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 27.6pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span lang="EN-US"><font color="#000000">20</font></span></p></td><td width="108" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 81pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 27.6pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span lang="EN-US"><font color="#000000">70</font></span></p></td><td width="120" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 90pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 27.6pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span lang="EN-US"><font color="#000000">100</font></span></p></td></tr><tr style="HEIGHT: 25.35pt;"><td width="169" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: windowtext 1.5pt solid; WIDTH: 126.8pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 25.35pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span style="FONT-FAMILY: 宋体;"><font color="#000000">乙方案</font></span></p></td><td width="107" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 80.2pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 25.35pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span lang="EN-US"><font color="#000000">10</font></span></p></td><td width="108" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 81pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 25.35pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span lang="EN-US"><font color="#000000">50</font></span></p></td><td width="120" style="BORDER-RIGHT: windowtext 1.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 90pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1.5pt solid; HEIGHT: 25.35pt;"><p class="MsoNormal" style="LINE-HEIGHT: 15pt;"><span lang="EN-US"><font color="#000000">160</font></span></p></td></tr></tbody></table><p class="MsoNormal" style="LAYOUT-GRID-MODE: char; LINE-HEIGHT: 15pt;"><font color="#000000"><span lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span><span style="FONT-FAMILY: 宋体;">试用<a name="baidusnap0"></a>决策树法选择最佳方案。</span></font></p><p class="MsoNormal" style="LAYOUT-GRID-MODE: char; TEXT-INDENT: 30.85pt; LINE-HEIGHT: 15pt;"><font color="#000000"><span style="FONT-FAMILY: 宋体;">依据已知条件，绘制决策树</span><span lang="EN-US">&nbsp;&nbsp;&nbsp; </span><span style="FONT-FAMILY: 宋体;">甲方案的期望值</span><span lang="EN-US">:=20×0.2+70×0.3+100×0.5=75</span></font></p><p class="MsoNormal" style="LAYOUT-GRID-MODE: char; TEXT-INDENT: 20.6pt; LINE-HEIGHT: 15pt;"><font color="#000000"><span style="FONT-FAMILY: 宋体;">乙方案的期望值</span><span lang="EN-US">:=10×0.2+50×0.3+160×0.5=97</span></font></p><p class="MsoNormal" style="LAYOUT-GRID-MODE: char; TEXT-INDENT: 20.6pt; LINE-HEIGHT: 15pt;"><font color="#000000"><span style="FONT-FAMILY: 宋体;">乙方案的期望值大于甲方案的期望值</span><span lang="EN-US">,</span><span style="FONT-FAMILY: 宋体;">所以选择乙方案。</span></font></p>