It's debatable. Ljungberg doesn't even have any managerial experience, unlike Solskjaer when he took over Man United, and it's tough to say he'll turn things around at Arsenal. Heck, I guess any decent manager out there would likely do a better job than the clueless Emery right now.
You never know with clubs who are desperate. Think Mourinho will do well in the short term, just not in the long term obviously.