Decision Trees <ul><li>Enable a business to quantify decision making </li></ul><ul><li>Useful when the outcomes are uncertain </li></ul><ul><li>Places a numerical value on likely or potential outcomes </li></ul><ul><li>Allows comparison of different possible decisions to be made </li></ul>
Decision Trees <ul><li>Limitations: </li></ul><ul><ul><li>How accurate is the data used in the construction of the tree? </li></ul></ul><ul><ul><li>How reliable are the estimates of the probabilities? </li></ul></ul><ul><ul><li>Data may be historical – does this data relate to real time? </li></ul></ul><ul><ul><li>Necessity of factoring in the qualitative factors – human resources, motivation, reaction, relations with suppliers and other stakeholders </li></ul></ul>
The Process Expand by opening new outlet Maintain current status Economic growth rises Economic growth declines 0.7 0.3 Expected outcome £300,000 Expected outcome -£500,000 £0 A square denotes the point where a decision is made, In this example, a business is contemplating opening a new outlet. The uncertainty is the state of the economy – if the economy continues to grow healthily the option is estimated to yield profits of £300,000. However, if the economy fails to grow as expected, the potential loss is estimated at £500,000. There is also the option to do nothing and maintain the current status quo! This would have an outcome of £0. The circle denotes the point where different outcomes could occur. The estimates of the probability and the knowledge of the expected outcome allow the firm to make a calculation of the likely return. In this example it is: Economic growth rises: 0.7 x £300,000 = £210,000 Economic growth declines: 0.3 x £500,000 = -£150,000 The calculation would suggest it is wise to go ahead with the decision ( a net ‘benefit’ figure of +£60,000)
The Process Expand by opening new outlet Maintain current status Economic growth rises Economic growth declines 0.5 0.5 Expected outcome £300,000 Expected outcome -£500,000 £0 Look what happens however if the probabilities change. If the firm is unsure of the potential for growth, it might estimate it at 50:50. In this case the outcomes will be: Economic growth rises: 0.5 x £300,000 = £150,000 Economic growth declines: 0.5 x -£500,000 = -£250,000 In this instance, the net benefit is -£100,000 – the decision looks less favourable!