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>
 <a 
  name="x35-50001f3"></a>
    Consider a decision tree algorithm attempting to find the
 right feature for a node. If the first query returns a value of <!--l. 2031--><math 
xmlns="http://www.w3.org/1998/Math/MathML" 
mode="inline">
 <mrow 
><msub><mrow 
><mover 
accent="true"><mrow 
><mi 
>D</mi></mrow><mo 
class="MathClass-op">&#x0302;</mo></mover></mrow><mrow 
><mi 
>&#x03C7;</mi></mrow></msub 
></mrow></math> with a confidence
 of <!--l. 2031--><math 
xmlns="http://www.w3.org/1998/Math/MathML" 
mode="inline">        <mrow 
><mi 
>&#x03B4;</mi></mrow></math>
 then the branching factor would be approximately <!--l. 2031--><math 
xmlns="http://www.w3.org/1998/Math/MathML" 
mode="inline">
 <mrow 
><mi 
>m</mi> <mo 
class="MathClass-punc">&#x22C5;</mo><msub><mrow 
><mover 
accent="true"><mrow 
><mi 
>I</mi></mrow><mo 
class="MathClass-op">&#x0302;</mo></mover></mrow><mrow 
><mi 
>&#x03C7;</mi></mrow></msub 
><mrow><mo 
class="MathClass-open">(</mo><mrow><mi 
>&#x03B4;</mi></mrow><mo 
class="MathClass-close">)</mo></mrow></mrow></math>.
 This branching factor would be approximately the same for further queries
 required by the algorithm to make a decision about what feature to use.
 This results in a total multiplied choice space size of approximately <!--l. 2031--><math 
xmlns="http://www.w3.org/1998/Math/MathML" 
mode="inline">
 <mrow 
><msup><mrow 
><mfenced separators="" 
open="["  close="]" ><mrow><mn>4</mn><mi 
>m</mi> <mo 
class="MathClass-punc">&#x22C5;</mo><msub><mrow 
><mover 
accent="true"><mrow 
><mi 
>I</mi></mrow><mo 
class="MathClass-op">&#x0302;</mo></mover></mrow><mrow 
><mi 
>&#x03C7;</mi></mrow></msub 
><mrow><mo 
class="MathClass-open">(</mo><mrow><mi 
>&#x03B4;</mi></mrow><mo 
class="MathClass-close">)</mo></mrow></mrow></mfenced></mrow><mrow 
><mi 
>F</mi></mrow></msup 
></mrow></math> which can be
 reduced to <!--l. 2031--><math 
xmlns="http://www.w3.org/1998/Math/MathML" 
mode="inline">        <mrow 
><mi 
>F</mi></mrow></math>
 or less using a batch query.
     
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