Description of problem:
Changed to device type RAID. Clicked Apply. Changed to raid0, clicked Apply. Beging installation.
The following was filed automatically by anaconda:
anaconda 19.24-1 exception report
Traceback (most recent call first):
  File "/usr/lib/python2.7/site-packages/blivet/devices.py", line 789, in create
    raise DeviceCreateError(str(e), self.name)
  File "/usr/lib/python2.7/site-packages/blivet/deviceaction.py", line 272, in execute
    self.device.create()
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 237, in processActions
    action.execute()
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 303, in doIt
    self.devicetree.processActions()
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 162, in turnOnFilesystems
    storage.doIt()
  File "/usr/lib64/python2.7/site-packages/pyanaconda/install.py", line 117, in doInstall
    turnOnFilesystems(storage, mountOnly=flags.flags.dirInstall)
  File "/usr/lib64/python2.7/threading.py", line 766, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/threads.py", line 141, in run
    threading.Thread.run(self, *args, **kwargs)
DeviceCreateError: ('mdcreate failed for /dev/md/nameroot: running mdadm --create /dev/md/nameroot --run --level=0 --raid-devices=4 --metadata=1.0 --bitmap=internal /dev/sda1 /dev/sdb1 /dev/sdc1 /dev/sdd1 failed', 'nameroot')

Version-Release number of selected component:
anaconda-19.24-1.fc19.x86_64

Additional info:
cmdline:        /usr/bin/python  /sbin/anaconda --liveinst --method=livecd:///dev/mapper/live-osimg-min --lang en_US.UTF-8
cmdline_file:   initrd=initrd0.img root=live:CDLABEL=Fedora-Live-Desktop-x86_64-19-Be rootfstype=auto ro rd.live.image quiet  rhgb rd.luks=0 rd.md=0 rd.dm=0  BOOT_IMAGE=vmlinuz0 
core_backtrace: 
executable:     /sbin/anaconda
hashmarkername: anaconda
kernel:         3.9.0-301.fc19.x86_64
other involved packages: python-blivet-0.12-1.fc19.noarch, python-libs-2.7.4-3.fc19.x86_64
packaging.log:  
product:        Fedora
release:        Fedora release 19 (Schrödinger’s Cat)
type:           anaconda
ureports_counter: 1
version:        19

Truncated backtrace:
Traceback (most recent call last):
  File "/usr/lib64/python2.7/site-packages/pyanaconda/threads.py", line 141, in run
    threading.Thread.run(self, *args, **kwargs)
  File "/usr/lib64/python2.7/threading.py", line 766, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/install.py", line 117, in doInstall
    turnOnFilesystems(storage, mountOnly=flags.flags.dirInstall)
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 162, in turnOnFilesystems
    storage.doIt()
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 303, in doIt
    self.devicetree.processActions()
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 237, in processActions
    action.execute()
  File "/usr/lib/python2.7/site-packages/blivet/deviceaction.py", line 272, in execute
    self.device.create()
  File "/usr/lib/python2.7/site-packages/blivet/devices.py", line 789, in create
    raise DeviceCreateError(str(e), self.name)
DeviceCreateError: ('mdcreate failed for /dev/md/nameroot: running mdadm --create /dev/md/nameroot --run --level=0 --raid-devices=4 --metadata=1.0 --bitmap=internal /dev/sda1 /dev/sdb1 /dev/sdc1 /dev/sdd1 failed', 'nameroot')