Minimizing and Maximizing Profile Key Values Programmatically

Question

Background:

One of our clients has contracted us to create a "siloing" feature on their site, using personalization. Basically, a visitor would come to the site and optionally self-identify as a particular type of professional. Each type of professional is associated with a single profile key and pattern card. If a user self-identifies as a particular type of professional, the visitor is scored to the max value of the associated profile key. Should the visitor re-identify as a different type of professional, the old identification is completely cleared out (set to the minimum value) and the new data is scored to the max.

Question:

This is the first time that I have had to set profile key values to a maximum or minimum. In Sitecore, I have set the maximum to 0 and the minimum to 100 for each of the profile key items that I have created. I know that these items do not control the profile key items that I am scoring in the code, but if in the code I set the scores to float.MinValue and float.MaxValue for minimum and maximum, respectively, will this cause an issue down the line for reporting?

Side-note:

The client does not intend to do any reporting/analytics based on this "siloing" feature. If they decide to add that in the future, we will add additional personalization events that do not get cleared out to the feature.

Answer 1

Background

The way in which you are using visitor profiles is non-standard, so I will first explain some details about the internals of the feature.

Once you've defined a set of profile keys, some pattern cards and profile cards, you would normally assign profile cards to your website pages. Every time a user visits a page that has an associated profile card, Sitecore will go over profile key values of the card and add the non-negative values of profile keys to the user's profile. There are two important conclusions:

1. The max value of user profile values is virtually unlimited and is not related to the max value of the corresponding profile key.
2. Profile values are not supposed to be negative.

When a user is matched to a pattern card, the matching process considers the user's profile and all available pattern cards into points in an N-dimensional space, where N is the number of defined profile keys. The profile is translated into a point based on the profile type (Sum, Percentage or Average).

Whichever pattern card point has the smallest Euclidean distance to the user profile point, that pattern card becomes the user's new matched pattern that will be used in personalization rules from that point on.

Recommendation

You are not using Sitecore's profile scoring feature, instead you override the profile to have specific values. Only one profile key will have a value greater than zero—both in the pattern cards and in the visitor profile. Which is why it doesn't really matter what values you use for the non-zero key.

I recommend that you put 0 to all profile keys and 1 to the one that you want to be matched to a specific pattern card. This is the simplest and least error-prone solution that will definitely work in your case.

Answer 2

In addition to @DmytroSchevchenko's answer, I want to provide a little extra insight into the code required to actually implement this.

As Dmytro mentioned, profile values are not supposed to be negative, and in fact the OOTB Profile class' Score() method checks to make sure that each score value is >= 0.0 and will only apply the score if it is. As such, a new class will need to be created to extend the Profile class and override the OOTB Score() method (which is virtual).

UPDATE:

Based on comments from Dmytro, I realized that rather than override the Score method, I can continue following the same pattern that Sitecore took with the Profile class' methods, and instead add a new RollBackScore method that is public and accepts an IEnumerable<KeyValuePair<string,float>> as a parameter. This is because the OOTB RollBackScore method that accepts the same parameter is unfortunately private.