<arg type='s' name='app_id' direction='in'/>
<arg type='a{sv}' name='select_rule' direction='in'/>
<arg type='i' name='error_code' direction='out'/>
- <arg type='a{sv}' name='statistics' direction='out'/>
+ <arg type='aa{sv}' name='statistics' direction='out'/>
</method>
<method name='Reset'>