SharePoint 2010 Search : Tuning Search (part 3) - The noindex Class & The Ratings Column

6. The noindex Class

One way SharePoint 2010 allows administrators and developers to manage noise in the search engine is by implementing the noindex class value in the HTML of the page. Of course, this works only for web pages or other content written with HTML. Many web pages are largely based on the same templates. These templates include branding and navigation so every web page looks the same or similar and has a similar navigational structure. This is friendly and familiar to web-browsing end users. However, a large number of the important terms for the organization appear on every document. That generates noise in the search engine. Adding this class value to tags in the HTML will tell the crawler not to index the content of those tags and focus only on the terms that appear in the "content" section of the web page.

To include the noindex class, simply find the tag that holds the content that should not be indexed. This is usually a header, footer, news Web Part, or navigation. Add the following values to that tag:

class="noindex"

It should be noted that some nested tags will require their own noindex class to respect the rule. Here is a typical example:

...
 <div class="noindex">
 <table>
 <tr>
 <td style="text-align:right;line-height:70%;">
 <a href=http://www.prosharepointsearch.com/about.html">About Us</a>
 </td>
 </tr>
...

7. Popularity (Click-Through)

Although not something that an administrator can actively modify to improve search, click-through relevancy adjustments can improve search without any administrative influence. This "social search" capability records a number of all the clicks for a given query with the document of choice. This document's ranking value is then, over time, increased to improve its ranking. This is an advantage insofar as the search engine learns based on the experience and knowledge of the end users. It relies on the fact that the end users know what they are looking for in respect to the query they made to find it. And they would naturally click the only document that is the correct one for their query. In actual practicality, this is probably not totally true. Users will click in and out of different documents, looking for the right one. This may or may not adversely affect ranking. However, over thousands, if not hundreds of thousands of queries, a useful pattern should emerge that will help ranking, not hinder it.

Should ranking appear to degrade over time, the Search service application can be removed and a new index, database, and ranking values applied to start again. At this point, there is no other way to manually affect this mechanism.

8. Social Tagging

Social tagging is a mechanism in SharePoint to allow users to personalize the content by adding tags to it. The tags can be anything the user wants and are unique to him or her. The tags can affect relevancy as well, helping content be handled by search. The term folksonomy is often applied to this type of user-generated tagging, and it is becoming more and more prevalent on web sites on the Internet. The concept is of a user-generated taxonomy that grows with user experience. Folksonomies can be a useful way to share interests and identify socially interesting concepts but should not be left as the core method for tagging and managing documents' taxonomies. A more managed structure should always be available for end users.

9. The Ratings Column

Although not technically part of adjusting relevancy, the ratings column can allow users to filter on results, along with the other search refinement mechanisms to find documents that are considered valuable by other users. The ratings column is a feature in SharePoint that will allow users to give documents in a given library or items in a list a rating by clicking from one to five stars in a column beside the document. Although this may seem trivial in an organization where all documents have value and purpose, if a given list or library is a collection of information on a given topic, the ratings column can allow users to rate and filter based on that what best represents that topic. The rating values can also be displayed on the results page to allow users to quickly identify which documents were ranked useful by their colleagues.

9.1. Adding a Ratings Column

To add a ratings column to a list or library follow these steps:

Figure 9. Including values in the search index

Figures 19 and 10 are two views of the same mapping, one from the crawled property and one (Figure 10) from the mapped property, which is the one we will eventually call from the user interface. One must be set for mapping the crawled property and the other to include its values in the search index.

Figure 10. Adding the AvgRating metadata mapping

9.2. Displaying Ratings in the Results

The next thing to do is to make this rating value visible in the result list. This will help users identify which documents are rated higher by their peers.

To add the ratings values to display on the results page, do the following:

Example 1. XSLT to display the rating stars<!-- Ratings -->

<xsl:choose>
<xsl:when test="avgrating &gt; 0 and avgrating &lt; .75">
                <span class="ms-currentRating"><img class="ms-rating_0_5"

 src="/_layouts/Images/Ratings.png" alt="Current average rating is half a star."/></span>
        </xsl:when>
        <xsl:when test="avgrating &gt;= .75 and avgrating &lt; 1.25">
                <span class="ms-currentRating"><img class="ms-rating_1"

 src="/_layouts/Images/Ratings.png" alt="Current average rating is 1 stars."/></span>

        </xsl:when>
<xsl:when test="avgrating &gt;= 1.25 and avgrating &lt; 1.75">
                <span class="ms-currentRating"><img class="ms-rating_1_5"

 src="/_layouts/Images/Ratings.png" alt="Current average rating is 1.5 stars."/></span>
        </xsl:when>
        <xsl:when test="avgrating &gt;= 1.75 and avgrating &lt; 2.25">
                <span class="ms-currentRating"><img class="ms-rating_2"

 src="/_layouts/Images/Ratings.png" alt="Current average rating is 2 stars."/></span>
        </xsl:when>
<xsl:when test="avgrating &gt;= 2.25 and avgrating &lt; 2.75">
                <span class="ms-currentRating"><img class="ms-rating_2_5"

 src="/_layouts/Images/Ratings.png" alt="Current average rating is 2.5 stars."/></span>
        </xsl:when>
        <xsl:when test="avgrating &gt;= 2.75 and avgrating &lt; 3.25">
                <span class="ms-currentRating"><img class="ms-rating_3"

 src="/_layouts/Images/Ratings.png" alt="Current average rating is 3 stars."/></span>
        </xsl:when>
<xsl:when test="avgrating &gt;= 3.25 and avgrating &lt; 3.75">
                <span class="ms-currentRating"><img class="ms-rating_3_5"

 src="/_layouts/Images/Ratings.png" alt="Current average rating is 3.5 stars."/></span>
        </xsl:when>
        <xsl:when test="avgrating &gt;= 3.75 and avgrating &lt; 4.25">
                <span class="ms-currentRating"><img class="ms-rating_4"

 src="/_layouts/Images/Ratings.png" alt="Current average rating is 4 stars."/></span>
        </xsl:when>
<xsl:when test="avgrating &gt;= 4.25 and avgrating &lt; 4.75">
                <span class="ms-currentRating"><img class="ms-rating_4_5"

 src="/_layouts/Images/Ratings.png" alt="Current average rating is 4.5 stars."/></span>
        </xsl:when>
        <xsl:when test="avgrating &gt;= 4.75">
                <span class="ms-currentRating"><img class="ms-rating_5"v
 src="/_layouts/Images/Ratings.png" alt="Current average rating is 5 stars."/></span>
        </xsl:when>

					  

<xsl:otherwise>
              <b>Not yet rated</b>
              <br/>
            </xsl:otherwise>
</xsl:choose>
<!-- Ratings End -->

The ratings should now appear on the result list. See Figure 11. This XSLT will check the value of the AvgRating property you have mapped and compare it with ranges between every half unit, starting at three-fourths. This will allow for half ratings based on the decimal values of the ows_AverageRating property, which is an average of all accumulated ratings.

The XSLT uses the built-in image Ratings.png, which is actually a larger image of all ratings stars, and sets them to be displayed using the built-in cascading style sheet (CSS). If the default CSS is changed, the ratings images will not display correctly. There are certainly more clever ways to create this XSLT, but this is a simple start to set the ratings value on the result template.

Figure 11. Ratings shown in the search results