At SMX East, WebMetro presented an eye-opener for SEMs on Google's keyword mapping algorithm. Senior Vice President Michael Behrens shared how online advertisers can take back control of their Google PPC campaigns.

1. Uncovering the Truth about Google
Keyword Mapping

2. Multiple Options… Which Keyword to Choose
Keywords
Search Query
• For A Typical Account ?
– Almost every search query will match more than one keyword
• If ‘wrong’ Ad-Group matches
– May show sub-optimal ad-copy or landing page!
• If more than one keyword is triggered over a short period of time
– Makes bid management harder, more keyword chaos
• Google publish rules for how keyword are matched to queries…
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3. How Google Determines which Keyword wins the Auction?
The Original Way After the 2008 Update
Use keyword matching query exactly Use keyword matching query exactly
(exactly matching) (exactly matching)
Use most restrictive match type (for Use most restrictive match type (for
same keyword) same keyword)
Use longer keyword (Match Length) Use longer keyword (Match
Length)**Ad Group Only
Use keyword with highest Ad-Rank
(Quality X Bid)
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4. Multiple Mappings: Same Query Mapping to Different Keywords
Visualization of queries (pink) and
keywords (blue).
Red lines show multi-mapped queries.
Queries triggering more
than one keyword
Result in chaotic account behavior
Severely reduce accuracy of
portfolio modeling and bidding
Create data integrity problems for
analysis
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5. Multiple Mappings: Example 2
Multi-Mapped
Queries
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6. Multiple Mappings: Example 3
Two of the top campaigns have severe mapping issues
providing little control and not allowing the bid
management platform to effectively execute models.
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7. Campaign vs. Ad Group Multiple Mapping
Cross Campaign Query Matching Cross Ad-Group Query Matching
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8. Multiple Mappings: Quantifying the Frequency
Keyword Counts by Query (30 Days)
60%
50%
40%
30%
20%
10%
0%
2 3 4 5 6 7 8
Non ‘Expected’ Multi-Match Queries
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9. So to determine the severity of the
problem and how much is
potentially caused by the Ad Rank
Rule we built our own search
engine with old school match rules
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10. Building a New Search Engine (Old School Rules)
1. Decide sensible criteria for ‘ideal’ matching
Rule (1) – Use keyword matching query exactly
Rule (2) – Use most restrictive match type
Rule (5) – Use longer keyword (match length)
2. Program a new matching algorithm
Use open source search engine Apache
3. Run search query stream through algorithm
Can take a long time, speed up using multi-core CPU
4. Pivot table results with KPI’s
Excel the results
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11. Mapping Definitions in the New Search Engine
Definition Description
Expected Expected keyword was matched to query (as per rules 1, 2 & 5)
MatchTypeLength A longer matching keyword (and/or narrow type) was found
ExactMiss An exact match keyword was found
ExactlyMiss An exactly matching keyword was found (broad or phrase)
NarrowerType The same keyword with a more restrictive type was found
NarrowerTypeBMM As above but specific to broad match modified type
Session Keyword was matched through session based matching
Duplicate Duplicate keywords were found
Ambiguous More than one keyword matched the query equally well
Unclassified Unable to classify match definition
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12. New Search Engine Results
Definition Cost Cost % Conv CPA CTR • Only 53% of the time
did our new rules
Expected $ 108,441 53.13% 604 179.5 6.1%
match Google’s actual
MatchTypeLength $ 48,566 23.79% 113 429.8 14.1% match selection.
Ambiguous $ 13,936 6.83% 37 376.6 8.9%
ExactMiss $ 9,185 4.50% 30 306.2 5.3% • Match Type Length
appears to be the most
Duplicate $ 8,812 4.32% 32 275.4 8.7%
frequently over-ridden
Session $ 7,665 3.76% 13 589.7 23.8% rule
Unclassified $ 4,152 2.03% 8 519.0 4.3% – CPA Higher
NarrowerTypeBMM $ 1,842 0.90% 3 614.0 12.8%
– Google’s Yield (CTR)
Higher
NarrowerType $ 1,190 0.58% 2 595.0 19.6%
ExactlyMiss $ 323 0.16% 15 21.5 14.1%
Grand Total $ 204,112 100.00% 857 238.2 7.1%
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13. New Search Engine Results:
Example Match Type Length Miss
KW Served
Best Match
Queries
In this example, a shorter keyword took precedence over a longer keyword

14. How can I take back control…
Use Negative Keywords
Force matching through negatives. The use of negatives is a great way to put up Google roadblocks and assist their
algorithms in selecting the right ad group by not allowing the wrong selection
Tightly Themed Ad-Groups
Maximize Ad Group match length rule. This will not help with creative as this rule only applies to the ad group, but
sometimes the bid is the biggest challenge for search marketers when it comes to inconsistent mapping
Remove Duplicates/Ambiguous
Sometimes a problem we uncover during account audits is the use of duplicate keywords. The problems is difficult
enough to manage without having to double your challenges by giving Google another eligible keyword.
Maintain Campaign Budgets
This can be deadly and can easily be isolated by running and IS Loss to Budget Report. Using budget capping to control
investment by campaign is sub optimal from a pure mathematical perspective and is a huge catalyst to cross campaign
multi mapping
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15. Thank you
Questions/Comments/Ideas….
Michaelb@webmetro.com
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