If you want to measure the effectiveness of your various AdWords campaigns, you probably turn to the analytics tools within your AdWords Dashboard. You see the number of clicks, impressions, your click through rate (CTR), and details about how many conversions correspond with your various ads and keywords, as well as your overall costs.

But perhaps your numbers aren't where you'd like them to be. You notice that certain keywords are generating a good number of clicks, but you're not seeing many conversions. Meanwhile, keywords that generate few clicks have high rates of conversion.

While there are a number of factors that can contribute to the success or failure of a PPC campaign, if you're only looking to your AdWords data, you're not seeing the complete picture. You're seeing the what, but not the why. This is often due to the common, but mistaken thinking that PPC ads alone lead to conversions.

To really gauge the performance of your PPC campaign, you need to pay close attention to the associated landing pages. Keeping this in mind, here's three web analytic metrics that can help you fully evaluated your PPC campaigns:

Average Visit Duration

They're clicking on your ad, but are they staying on your site once they get there? That's what "average visit duration" can help you determine.

What's considered to be low average visit duration varies from campaign to campaign, as well as what's required of a customer once they reach your landing page. Let's say the call-to-action asks the prospect to fill out a form. Does your low average visit duration match up with the average amount of time that would be needed to complete the form? If so, this can be a sign of an effective landing page.

If the average time is lower than what would be reasonably needed to complete the call-to-action, this can be a sign of an ineffective landing page. Perhaps the form is confusing or asking prospects to give an amount of information they aren't comfortable with. Adjust the form and see if this improves your average visit time.

A low average visit duration could also indicate that something isn't matching up between your ad copy and it's associated landing page, meaning a prospect is clicking on your ad expecting to find one thing, only to find something else once they are taken to your site. Adjust the content or specific landing page associated with that ad. And make sure that they compliment each other, using similar keywords, and fitting thematically.

Slow site load times can also effect your average visit duration. If your average is extremely low (less than three seconds), take a look your site speed averages in Google Analytics. Slow load times might be dragging your efforts down. And statistics show that if a site takes more than four seconds to load, visitors are likely to click off and go back to their search results for something else.

Bounce Rate

If a visitor lands on your site and leaves without viewing any other pages, this is referred to as a bounce. Again, what's considered a high bounce rate will vary based on the business and the campaign. In general, a bounce rate less than 50% is considered good, as it means half of your visitors are staying on your site after being brought to a landing page.

But what if your landing page contains a lead form or a phone number? In this case, you are hoping that prospects will convert from the landing page itself, meaning you'd ideally see a higher bounce rate, 80% or above.

Again, the relevance of your ad copy to your landing page for that ad can have a major impact on how high or low your bounce rates are for each keyword and campaign. If you're seeing higher than expected bounce rates, take a look at what kinds of expectations your ad copy sets up for it's associated landing page. Does the content match up?

Pages Per Visit

When looking at your average pages per visit metric, you want to be aware of any extreme highs or lows. On one hand, a high page per visit average means prospects are not only finding your site, but staying on it.

However, if they aren't ultimately converting after viewing a number of pages, it could be a sign that potential customers don't find the content on your site useful, and are opting to go back to the search results to find a more relevant site.

The same can be said for a low amount of pages per visit, except in this scenario, they are landing on your page, but find it's not relevant to their search. Another cause of low pages per visit could be that the prospect isn't sure what to do after viewing your landing page. Does the page tell customers what to do next? Or are they left to their own devices?

An effective PPC campaign drives clicks to your site. An effective landing page helps convert. That's why it's important to review and adjust each on a regular basis. Monitor your progress and test accordingly.

If your ads or landing pages include phone numbers, it's important that you consider the impact offline phone call conversions are having. By implementing a session-level call tracking software, you'll be able to see which keywords, ads, and landing pages are leading to those offline conversions, data that without call tracking would be lost forever.

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