How to exclude directories from phpunit coverage report

I tried the following configuration:

<?xml version="1.0" encoding="UTF-8"?>
<phpunit>
    <testsuites>
      <testsuite name="My Test Suite">
         <directory suffix=".php">Test/Case/Model</directory>
        <exclude>Test/Case/Model/Behavior</exclude>
      </testsuite>
    </testsuites>
</phpunit>

but it does not exclude the behaviour from coverage report. How to exclude these directories or files from the coverage report?

Refer to the exclude element phpunit documentation.

Here is an example phpunit.xml:

<?xml version="1.0" encoding="utf-8"?>
<phpunit>
  <filter>
    <whitelist>
      <directory suffix=".php">../</directory>
      <exclude>
        <file>../ext_emconf.php</file>
        <directory suffix=".php">../tests</directory>
      </exclude>
    </whitelist>
  </filter>
</phpunit>