Web Operations

Chapter 11. How Your Visitors Feel: User-Facing Metrics

Alistair Croll

Sean Power

IT OPERATORS ONCE CONCERNED THEMSELVES only with the health of their underlying infrastructure. The thinking went something like this: if the platforms on which the application was running were healthy, the user experience was good, too.

Today, we know this is not the case. A far larger percentage of the applications we build are web based and face a vast, unknown user base. End-user metrics are as critical to the success of a website as backend metrics. What's more, sudden problems with end-user metrics such as availability and page latency are often the first sign that something's wrong with the infrastructure.

Web operators need to know about four major categories of end-user measurements, as shown in Table 11-1.

Table 11-1. The four kinds of end-user metrics

Type of metric	What it's used for	Questions it answers	Who cares most about it
Web analytics	Tracks visitors as they use the site to see whether they did what you wanted them to	What percentage of visitors bought a product? Which segment of visitors is most likely to invite friends? Which content makes people stay longer?	Marketers and merchandisers, product managers
Web performance	Measures the health of the site from the outside perspective	How long does it take to deliver a page to a visitor? Where is the site slowest from? What percentage of the time is the site working properly?	IT operators and those responsible for service levels
Web Interaction Analytics ...