Social Media Mining: An Introduction

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CUUS2079-END CUUS2079-Zafarani 978 1 107 01885 3 January 13, 2014 19:33

Notes 297

7. In the original paper, instead ofa, the authors use ln(a+1) as the variable. This
   helps remove the effect of a power-law distribution in the number of activated
   friends. Here, for simplicity, we use the nonlogarithmic form.


8. Note that maximizing this term is equivalent to maximizing the logarithm; this is
   where Equation8.41comes into play.

Chapter 9

1. In Matlab, this can be performed using thesvdcommand.