How the measurement is done

Pavel Brecik
A free video tutorial from Pavel Brecik
Web Analyst and Data Evangelist
4.4 instructor rating • 3 courses • 14,047 students

Learn more from the full course

Ultimate Google Analytics course + 50 practical examples

Practical Google Analytics course based on real experience including 50 practical examples + 100 quiz questions

04:40:45 of on-demand video • Updated February 2021

  • Understand how the tool works, what data is there and the most important find the business value in it
  • Ability to make the right data decisions
  • Know which are important Google Analytics reports
  • Among others we'll go through 50 practical examples!
  • You'll practice achieved knowledge with 100 quiz questions
  • How to think in context and not act hastily
English Google Analytics measurement is based on cookies. And don't worry not the ones you buy in the store. In tech terminology cookies are small files stored in a browser and I stress the word browser. They have limited size and they don't store any information about the pages viewed before or how many times you've already visited a website. For purposes of Google Analytics cookie is just identifier of user or to be more precise browser. So, yes the number of users we all see in our accounts is in fact the number of browsers that visited our website. Let's have a close look on how GA cookie looks like. So this is how Google Analytics cookie looks like. Pretty simple right. We have a couple of numbers in here separated by dots. Lets in more detail what it actually means. So GA dot one dot two is every time the same. And it's the version of Google Analytics measurement. It's everything the same. So we don't have to worry about it that much. Then we have two more number sequences. The first one is actually nothing but the random number. It's generated by javascript measurement code which you all have on your website. And then the second one is the first timestamp. This is actually the time when you for the first time visited a website. And these two numbers together make something we call Client ID which is user unique identification. And as we know the user is nothing but a browser. So this is actually the client id that measurement code takes every time you visit a website and he's able to recognize you as the same user who has already been on the website. We already know that GA is one huge table. To make it work correctly. it's of course necessary to have the javascript snippet on every page of your website. Once it's loaded together with the rest of your website's code in a very simplified version it only sends information that some users who we know is a browser has viewed a certain page at certain time. Time is represented by a timestamp which is nothing but time format. And this is it. There is of course some more information sent but for understanding of how it works it's OK to remember just this. Try to imagine a simple scenario: You typed URL address into your browser and your browser is now downloading and parsing an HTML code. Part of this code is also Google Analytics code which ensures measurement and once it's loaded it asks your browser a question: Is there a Google Analytics cookie? If yes, it takes the client id from it and knows it's returning visitor if not it's a signal for a GA code that it has to create a cookie and take the Client ID from it. Either way we now have a Google Analytics cookie so we can send all the information on Google Analytics servers. This is exactly how Google Analytics server call looks like. We are calling a GA server. We are sending there an information that we're viewing a page, we want to send it into this particular Google Analytics account. UA-123456-1 We are sending there information that this is our client id which we took from GA cookie and were sending there an information that we just viewed this particular URL called contact page. Once all this information hit google analytics server they are parsed there and stored in a database, which we know is a huge table. After that we are able to see all the beautiful charts and tables in the interface. And now let's take a look at the very basic metrics definition. We have to start with the users as humans, real people who can visit your website and now we have to make a switch to who is user from Google Analytics perspective. They are browsers. Yes browsers. And even if you use the same computer on which you have three browsers from Google Analytics perspective you will be taken as three users. Every user can make a session during which he or she can view multiple pages. So this is the very simple definition of how we got from users as humans to page views. And now we're going to look of how the session is define. Session might seem as something so obvious that we wouldn't even think about its definition. I think it's worth remembering of how exactly the session is defined in Google Analytics. It's the group of user interactions with website and by interaction I mean mostly page views, Some events like adding products into cart or a transaction. And here we have a very nice example of how a session can look like. We have a user who viewed four pages he started at nine o'clock and we have an exit at 9:25. Next thing good to know is that there are three possibilities of when a session can expire. The first one is midnight. So if you're browsing a website around midnight, the first page view after a midnight starts a new session. The second case is when you arrive via different campaign either by clicking on a banner or clicking on a different result from a search engine. And the third and I think the most common case is so-called inactivity window. This window is by default set to 30 minutes. Let's have a look on the second example to see what I mean. As you can see the second session starts very much like the first one up to the second page view. As we can see there is exactly a 40 minutes window. And as we said by default the inactivity window is set to 30 minutes which means that the third page view starts a new session. The inactivity window can be adjusted in the interface. It can be either shorten just a few seconds or prolonged to a couple of hours. There's one more metric we have to define it's conversion rate. And we will use it very often during this course. Sometimes it's almost the holy grail for all the marketers. It's the percentage of sessions that completed a goal. A goal can be purchase, sending a lead, reading more than five pages on a blog and so on. In-general goal is any action ww define and take as component by which we evaluate our website. A quick example of how it's calculated. Let's assume we have 1000 sessions from which 25 purchased something. 25 divided by 1000 is 2.5% 2.5% The higher, the better. Try to remember this one because we'll use it often in the upcoming lessons.