• by Laurie Sullivan  @lauriesullivan, December 9, 2010

About 22% of Google searches in October were done using Google Instant, head terms continue to gain importance, and searchers see more ads per search session. This is according to comScore Search Evangelist Eli Goodman, who unveiled research Thursday on the impact of Google Instant on search and advertisers at the MediaPost Search Insider Summit in Park City, Utah.

Goodman told attendees the number of core searches across Google's search engine rose from 17.0 billion queries in August to 17.7 billion in September to 18.4 billion in October. The research firm uses August and October because the two represent full cycles of either no or full Google Instant for the entire month.

Search penetration in August 2010 reached 82% vs. October 2010 at 83%. Sessions per user for the months came in at 19.5 vs. 20.1, and the key driver queries per session came in at 2.5 vs. 2.75, respectively. Goodman says queries per session and queries per user attributed roughly half to Google Instant. This analysis is limited to Google Web Search, as opposed to core search.

The research also looked at the impact on query length. There are two types of queries that can be measured: typed vs. suggested by Instant. comScore has seen two interesting phenomena take place. First, Google Instant is effectively reducing the amount of typing users do, a prime objective of the feature. But it also reduces the length of the queries submitted by 17% in terms of characters and 3% in words.

Instant appears to drive users toward head terms, as demonstrated by reduced query length and an increase in branded searches. The search tool exposes searchers to more ads, although the influence is likely dampened somewhat by lower click-through rates, Goodman says. While it's way too early to say with any certainty what the impact will be, comScore did find that searches in Google Instant are 15% more likely to have ads because more are brand terms. The number of ads per search is not statistically significant.

While Correlation isn't causation, Google has increased loyalty since launching Google Instant. Looking at how Instant impacts loyalty, comScore looked at that primary user base and share of requirements. The research firm examined the percentage of each engine user base that relies on the engine as their primary tool -- more than half of their searches. In this scenario, Google saw a small increase in those months.

comScore also looked at the average share of requirement for each engine. So, Google users conducted an average of 76% of their searches on the engine in October, compared with 72% in August.

Squashing another misnomer, Goodman says "the system is not being gamed in any capacity" and comScore has not seen any issue with Google pushing out any categories. When Google Instant launched, the blogosphere lit up with the belief that the engine would favor certain topics to their financial benefit. Not true, he says.

Google Instant, like slide shows and contextual search, is a clear example of the evolution in search. While no measurement system is perfect, comScore believes it has found a good way to measure impact. Goodman defines "Explicit Search" as searches entered with user intent. "Implicit Search" is when query results are presented. And although the searcher takes no action, the query counts because of the three-second rule.