A few of the common dimensions in Google Analytics are user, session, and interaction. An example of a user dimension is a geographic location. An example of a session dimension is a traffic source. An example of an interaction dimension is an action a user takes on your site, it could be a page title. Metrics help you understand the behavior of your users. Metrics count how often things happen. For example, the total number of users on a website or app. This would be considered an Audience metric. A behavior metric tracked is the average number of page views. This is calculated by the total number of page views divided by the total number of visitors, to give you a page view average. Google Analytics can also be configured to track conversion metrics, as I've discussed in a previous blog post.
The metric called Visitors or Users measures the number of unique users that visit your site during a specific time period. Visitors can be divided in to two groups, new and returning users. Sessions also known as Visits, are defined as a period of consecutive activity by the same user. A session persists until a user stops interacting for 30 minutes. This is the default session timeout length. This can be changed in Google Analytics configuration settings.
Page view counts every time a page is viewed. Google Analytics can also track other interactions, such as each time a video is viewed. These are called events. Events require customizations to your implementation. These events keep a page view "active." By default, once a visitor stops engaging, or generating events for more than 30 minutes their session expires.
All of the time-based metrics rely on hits or a stream of user activity to be calculated properly. Google Analytics tracks when each interaction happens. They take the last interaction and subtract it from the first to determine the length of the visit duration. To calculate time on page they take the time they landed on a particular page and subtracts the time from the next page view.
Another important metric to understand are bounce rates. Bounce rates are the percentage of sessions with only one user interaction. The goal is to have this number very low if possible. For example, when I first setup this blogger site my bounce rate was 99.99% something ridiculously high. Bounce rates are counted when someone lands on your site and then leaves immediately. A bounce is counted if they only visit one page and do not generate any other events or interactions. There is no second interaction to track visit duration or time on page.
Why might you have a high bounce rate?
- Setting the wrong expectations
- Poor user experience on landing page