Hi!<br><div class="gmail_quote"><br>I haven&#39;t found any answer to this problem online, and so am hoping that someone can help me here.<br>I need to:<br>a) create a new series that comprises only the positive observation of a series<br>
b) only use the observations for which the new series are not equal to 0 in a NLS <br>
<br>How would I go about that?<br><br>Thanks in advance for your help!<br><br>Caroline Landry<br>
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