Google Analytics & 'no data'

[pcun]

I'm using GA for several websites. When I look at the keywords visitors use to get to certain pages, there is always a substantial number of visits with the 'no data' keyword.

Does anybody have an answer as to why this is and how I can get the actual data.

Also, why is it that the website being monitored is also sometimes the top referral site?

[pcun]

What the "no data" means is that there was no keyword set when the visitor
started the session if they came from a campaign. This can happen for a
variety of reasons, but sometimes it can be the result of the visitors
hitting a redirect before landing on your site and the keyword information
gets lost due to the redirect.

There are a couple of reasons due to which a website may appear as a
self-referral.

1. Redirect. Generally, a website may appear as a self-referral if there
is a redirect. If a website redirects from www.example.com to
www.domain.com, Google Analytics will record the referral as
www.example.com. When the user is redirected, the tracking code records
the referral source as website the user was redirected from. If there is a
redirect on your website, we suggest you remove the redirect or add the
redirected URL as the Website URL in your account. Your webmaster or your
hosting company should be able to assist you in removing the redirect.

2. Frames: Frames may also result in self-referrals. This is because a
frame in your website may be used to load another webpage.

3. Tracking code not installed on all of the web pages: If the tracking
code is not installed on all of your webpages, Google Analytics will not
be able to track the referral webpage and will assume the previous page to
be a referral.

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I'm still not happy why the 'no data' figure can be so high sometimes.
I'm looking for further information on the 'variety of reasons' why this may be happening.