Properties of the XML representation:
Generate xsi namespace? - Used for emitting the standard definition of the xsi namespace prefix which is associated with the http://www.w3.org/2001/XMLSchema-instance namespace. This is useful if you are using the Null Value Support in XML documents and don't wish to have a Namespace Container just to define the xsi namespace.
Omit XML declaration on output - When you select this checkbox, the XML output of a map will not start with the usual XML declaration <?xml version ="1.0"?>. This is useful when you want to append multiple XML documents in a single file.
See also the common properties associated with representations.