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Website Optimization Metrics Chapter 10

Without quantifiable metrics, website optimization (WSO) is a guessing game. But with hundreds of billions of e-commerce dollars at stake, most companies cannot afford to guess.

With web metrics, you can progressively improve your search engine marketing (SEM) campaigns, conversion rates, and website performance. The results of using these controlled experiments are more profits, happier customers, and higher return on investment (ROI). The folks at Amazon.com have a saying that nicely sums up the gist of this chapter: “data trumps intuition.”

Nevertheless, website owners are awash in a sea of data. With such a surfeit of statistics the variety of metrics available to analyze can be overwhelming. You can use web analytics software such as WebTrends to analyze server log data and provide standardized reports. But how do you choose the best metrics to measure website success? How do you best run controlled experiments such as A/B split tests, multivariate tests, and parallel flights? What is the best Overall Evaluation Criterion (OEC) for your particular goal?

This chapter will boil down this statistical tsunami to highlight the most effective metrics and techniques that you can use to optimize the effectiveness of your website. We show the most effective metrics for each subject area (SEM and performance), selected metrics in action, and show the best tools that you can use to measure and tweak websites. Let the optimization begin!

What follows is an outline of this chapter:


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is a metric developed by Paul Holstein of CableOrganizer.com.
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In Web- Net 2000 (San Antonio, TX: October 30-November 4, 2000), 227-232. Round-trip times range from 20 to 90 ms across the United States. Overseas RTT ranged from 140 to 750 ms for a satellite link to Bangladesh. About 40% to 60% of total web page latency is from the initial request to receiving the first byte, due mainly to overhead, not server delay.
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A service level agreement (SLA)
is a formally negotiated agreement between two parties that records a common understanding of the level of service.

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