The hotel problem

May 16, 2008 in Google Analytics: What it is
Tags: naman chakraborty, namanchakraborty, bihar, www.yahoo.com, www.google.com, The hotel problem. analytics, www.wikipedia.org, computer peripherals, banana bar, monza bar, bandra, santa cruz, motihari, aurangabad, hastinapur, dilhi jal board, uttar pradesh, uttaranchal, jharkhand, hawa mahal, jaipur, rajasthan, rawatbhata, thermal power project, web analytics, excelan, kanwal@rekhi.com, TIE, New visitors + repeat visitors unequal to total visitor

A very famous problem in analytics. It deals with the problem of the cumulative total of unique visitor, per day of the month not adding up to the total number of unique visitors that month. It has baffled the new analytics professionals for a long time and probably is the first problem that is encountered, by a new analytics professional.

An inexperienced user may tend to take it as an anomaly with the software and the

The way to picture the situation is by imagining a hotel. The hotel has two rooms (Room A and Room B).

	Day 1	Day 2	Day 3	Total
Room A	John	John	Jane	2 Unique Users
Room B	Mark	Jane	Mark	2 Unique Users
Total	2	2	2	?

 

 

Thus there is a concept which is as follows:

New visitors + repeat visitors unequal to total visitors

 

Another common misconception in web analytics is that the sum of the new visitors and the repeat visitors ought to be the total number of visitors. Again this becomes clear if the visitors are viewed as individuals on a small scale, but still causes a large number of complaints that analytics software cannot be working because of a failure to understand the metrics.

Here the culprit is the metric of a new visitor. There is really no such thing as a new visitor when you are considering a web site from an ongoing perspective. If a visitor makes their first visit on a given day and then returns to the web site on the same day they are both a new visitor and a repeat visitor for that day. So if we look at them as an individual which are they? The answer has to be both, so the definition of the metric is at fault.

A new visitor is not an individual; it is a fact of the web measurement. For this reason it is easiest to conceptualize the same facet as a first visit (or first session). This resolves the conflict and so removes the confusion. Nobody expects the number of first visits to add to the number of repeat visitors to give the total number of visitors. The metric will have the same number as the new visitors, but it is clearer that it will not add in this fashion.

On the day in question there was a first visit made by our chosen individual. There was also a repeat visit made by the same individual. The number of first visits and the number of repeat visits will add up to the total number of visits for that day.

Some related links on www.wikipedia.com

• Web log analysis software
• Web bug
• Business Intelligence
• Customer engagement
• Win-loss analytics
• Emetrics Summit
• Path analysis

• Web Traffic Data Sources and Vendor Comparison by GA Experts

• Naor, Moni; Pinkas, Benny (1998). “Secure and Efficient Metering“. Advances in Cryptology – EUROCRYPT 1998: International Conference on the Theory and application of Cryptographic Techniques. Retrieved on 2007-12-27. 

• Naor, Moni; Pinkas, Benny (April 14-18, 1998). “Secure Accounting and Auditing on the Web“. Seventh International World-Wide Web (WWW) Conference, 1998. Retrieved on 2007-12-27. 

• Franklin, Matthew; Malkhi, Dahlia (1998). “Auditable Metering with Lightweight Security” (PostScript). Journal of Computer Security, 1998 6 (4): 237-256. Retrieved on 2007-12-27.