Views Arguments Title
Edit your argument for configuration
Add validator options for your argument by selecting PHP Code from the select box
Add following code in it

 $usr = user_load(array(uid =&gt; (int)arg(2))) //Check the appropriate position of uid
 $view-&gt;display['page_2']-&gt;handler-&gt;handlers['argument']['date_argument']-&gt;options['title'] = $usr-&gt;field_first_name . "'s content";


Here page_2 is views identifier and date_argument is argument identifier.