Google analytics work fine for small and medium-sized websites, but when the data volume increases, some of the reports are sampled. See in this presentation some of the most common issues and how you can overcome them.
- 1. Google Analytics sampling limitations and how to overcome them GeorgePapadongonas WebAnalyst,AmazeeMetrics 16/7/2013
2. How Google Analytics stores data All unfiltered data of a web property (up to 10 million hits per month) are stored in the Google Analytics database Each standard report has an associated data table in the Google Analytics database with unsampled data Reports for accounts with more than 200,000 visits per day are processed daily Reports for accounts with less than 200,000 visits per day are processed more often 2 3. Google Analytics Report Sampling Sampling starts when the requested date range has more than 500,000 visits The sample size can be arranged by using the Google Analytics sampling slider. The default setting is for 250,000 visits, maximum setting is 500,000 Visits are counted for the specific date range on a Web Property level, not on a Profile level Standard reports without filters, advanced segments or secondary dimensions use always unsampled data Sampling applies to custom reports 3 4. Organic Search trac report is unsampled 4 5. By adding a second dimension, sampling is applied 5 6. Adjust the sampling size 6 7. Prefer the higher precision setting 7 8. Google Analytics Report Sampling 8 9. How sampling is calculated Web property has 24,580,303 visits Profile has 492,786 visits Default sampling is: 250,000x492,786/24,580,303 = 5,012 visits (1%) Maximum sampling is: 500,000x492,786/24,580,303 = 10,024 visits (2%) 9 10. Avoid the faster processing setting 10 11. Prefer the higher precision setting 11 12. Pageviews or events reports can be unreliable 12 13. Google Analytics Report Sampling Visits and Visitors reports are usually reliable, even with a small sample E-commerce transactions, individual pageviews, adwords data, revenue and goal conversions are less reliable 13 14. Solutions 14 15. 1. Buy Google Analytics Premium Only$150.000 / year 1 Billion hits processed per month Unsampled reports Data processing every 4 hours 15 16. 2. Create custom profiles Instead of creating reports with specific advanced segments, create custom profiles using filters The default reports of all profiles are always unsampled, even if the visitors are more than 500,000 16 17. 3. Enable Data Sampling Sample your data , by adding a line in the Google Analytics tracking code code_gaq.push(['_setSampleRate', '80']); Sets sampling rate at 80% Not a perfect solution, as the data are still sampled, but you have control and can avoid tracking interruption (for more than 10 million hits per month) 17 18. 4. Use smaller date range Break you report in smaller data ranges, each one having less than 500.000 visits This ensures that the data are unsampled Export the reports using the Google Analytics API Aggregate the data in Excel and create the master report 18 19. 5. Use analyticscanvas.com Analytics Canvas oers query partitioning, using the Google Analytics API. Reports are exported in smaller date ranges, so that they are unsampled and they are then merged automatically with Analytics Canvas. 19 20. 6. Download Google Analytics data locally It is possible to keep a local copy of Google Analytics data Add a line in the Google Analytics tracking code _gaq.push(['_setLocalRemoteServerMode']); Add _utm.gif to your web server root 20 21. 6. Download Google Analytics data locally 126.96.36.199 www.mysite.com - [01/Oct/2007:03:34:02 +0100] "GET /__utm.gif?utmwv=1&utmt=var&utmn= 2108116629 HTTP/1.1" 200 35 "http://www.mysite.com/pageX.htm" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 1.1.4322)" "__utma=1.117971038.1175394730.1175394730.1175394730.1; __utmb=1; __utmc=1; __utmz=1.1175394730.1.1.utmcid=23|utmgclid=CP-Bssq-oIsCFQMrlAodeUThgA| utmccn=(not+set)|utmcmd=(not+set)|utmctr=looking+for+site; __utmv=1.Section One" 21 Data are recorded in the server log files Use http://analytics.angelfishstats.com/ to analyze them, as Urchin is discontiniued 22. Thanks! 22