Sep 252013

Controlling Google's Inconsistent PLA Target Serving

Many moons ago, RKG's George Michie wrote a post lamenting the fact that Google will often serve broad match keywords with higher bids over an exact match term that matches the query but has a lower bid. This phenomenon shouldn't happen according to Google's own literature, which details that a keyword should only be served in the place of a more closely matching keyword if it has a lower bid and higher ad rank.

Our own experience has proven this to be inaccurate, however, and diving into the way Google's Product Listing Ads autotargets are served, we find much the same story.

Different levels of PLA autotargets act in much the same way as matchtypes. A Product ID target can only be served if the product shown through PLAs exactly matches that ID, much like an exact match keyword can only
be served if the query exactly matches the keyword.

Broader targets, such as All Products, adwords_grouping and product_type behave more like broad match keywords, with the granularity of the target controlling the scope of how many products can be served through these targets.

As such, it would seem that the optimal strategy for PLAs would be to have as much traffic going to Product ID targets as possible, so that bids are calculated at this most granular level. However, this isn't as simple as it sounds.

Higher Bids Rule Most of the Time

Google recommends that advertisers keep an All Products target active in their PLA campaigns as a catch all to 'ensure that all of the products in the product feed are eligible to show' through PLAs. At RKG, we've found that if Product ID bids are carefully monitored and kept above the bids for broader targets, such as All Products, that the product may fall under, the Product ID targets can get close to 100% of the traffic that goes to the products that have these targets.

This isn't always the case, however, as there are instances where Google seems to ignore Product ID targets regardless of bids. For example, a Product ID target for one advertiser was launched with a bid that was 85% higher than the All Products target, yet Google ignored the more granular target and instead sent hundreds of clicks a week to the All Products target.

This is problematic for a couple of reasons:

1)      The reason the Product ID was launched with a higher bid was because this was a well performing SKU and we wanted more PLA traffic on it. Funneling this traffic to the All Products target with a lower bid keeps us from being able to dial up traffic on this particular item.

2)      The All Products target was absorbing all of the well performing traffic on that Product ID, which performed at a significantly higher sales per click than the All Products target as a whole. Thus, the apparent performance of the All Products target is inflated.

While instances like these appear to be the exception, it still doesn't make very much sense that the broader target would be served with a lower bid, and draws into question how well Google is able to assign quality score to a Product ID target. This is especially true of accounts that have long standing active All Products targets when the Product IDs are added. As Google has more history for the All Products target, this target is assigned a higher quality score and garners traffic that could have gone to more granular targets.

In order to combat this, RKG has found that by slowly raising the bids for more granular targets while at the same time reducing the bid for the All Products target, traffic will slowly move over to the more granular targets.

No Point to Granular Targets with Low Bids?

Most paid search advertisers aim to hit a certain cost to sales ratio as their primary efficiency metric.  If sales per click goes up, the advertiser can afford to bid more at the same efficiency, and they will drive more traffic.

This carries over to PLAs as well. Similar to keywords, though, Google will often choose to serve less granular targets if the bids are higher than those for more granular targets that could be served.

In situations where a particular product is getting a lot of traffic under a broader target but not performing as well as other products in that target, it would be nice to be able to launch a Product ID target with a lower bid to maintain efficiency for this traffic. With the target cascade method of serving that Google is currently using, however, this seems impossible as the broader target with the higher bid will absorb the traffic while the Product ID target is ignored.

Lack of Control for Shifts in Demand

Shifts in consumer demand for a product can drive the PLA performance of a particular product up or down quickly. Even if an advertiser launches a Product ID target with a higher bid than those for more general targets because the product is performing well, performance for that product could become worse than that of broader targets at any time.

In this case it would be best if the Product ID target could be bid down below the broader targets in order to maintain the return on ad spend for that product. This traffic would mostly just go to the broader targets, however, rendering the Product ID target useless unless performance picks back up and allows the advertiser to increase the Product ID bid back above the broader targets.

Controlling Traffic with Negatives

In the case of broad match keywords superseding exact match terms with lower bids, one solution that works fairly well is to apply exact match negatives for all exact match keywords to broad match terms. This eliminates the broad match terms from being triggered for those searches.

Negatives can be used similarly with PLA targets in order to prevent different targets from showing on particular queries for which an advertiser would prefer to show a different product. For example, if an advertiser were selling the new iPhone 5c and there was a Product ID target, it would make sense to add negatives such as 'iPhone 4' to the ID target to prevent that product from showing to people searching for the older model.

One aspect where the keyword matchtype to PLA target type analogy differs, however, is that a Product ID can be triggered by multiple relevant queries, whereas an exact match term can only be triggered by one query. This makes it more difficult to control traffic for a product from going to a broader target as many different negatives would need to be added. These negatives would also have to be added not only to the All Products target, but any category level targets that the Product ID may fall under as well.

In the iPhone 5c example, this product could be triggered by queries as broad as 'cellphone' or 'smart phone.' In order to keep an All Products target from showing the iPhone 5c product for which there is an ID target, negatives for these broader queries might have to be added to keep that product from showing through the broader target. Further, if there is a category target such as 'iPhones' that the iPhone 5c also falls under, those negatives would have to be added for this target as well.

Thus, while negatives do help to control which targets get traffic from different keywords, they are difficult to implement if the goal is to shift traffic for a product from a broader target to a more targeted one.


If you're going to launch more granular targets for PLAs, whether they be more specific category targets or Product IDs, it makes the most sense to launch only those that you have the ability to bid more for than the more general targets that the products in these targets could fall under, such as All Products. Otherwise, the traffic will, for the most part, just be headed to the broader targets.

It would be nice if Google provided some way to prevent broader targets from getting traffic on products that have Product ID targets launched. This could either be through back end adjustments that Google makes to ensure the more granular target is respected, or by allowing advertisers to block specific IDs from being shown through broader targets with ID negatives. As Bing begins to flesh out their own product ads, I hope they'll consider building such functionality into their approach.


11 Responses to "Controlling Google's Inconsistent PLA Target Serving"
Paul Rice says:
Great article Andy. I agree that Google should use product "ID negatives" as a way to force traffic to the proper target. That is the ultimate solution.
Peter Humleker says:
It's actually pretty simple as long as you have an ad group for each individual product. If you're using a 'catchall campaign' then you set the max cpc to $.05 cents and the other PLA campaigns to a higher than $.05 max cpc. So the other PLA campaigns would be .15 cents, .20 cents etc.. or individual bids for each product as long as minimum bid is higher than .05 cents. Then throw your junk search terms like 'iphone', 'smart phone', 'cell phone' etc into a negative keyword list in your 'Shared Library' so that those terms are negative keywords in all campaigns EXCEPT your catchall. This way your catchall with max cpc of .05 cents picks up those very broad terms and your campaigns with granular product id's like 'iphone 5s' will show for those search terms. If Google shows the wrong pla to a search term, for example search term is 'iphone 4s' and Google shows your pla ad group for product 'iphone 5s' you just make that search term a negative keyword at the "Ad Group" level.... This forces Google to show the correct product next time that search term shows up. I've had great success using the above strategies. Hope it helps others! Peter
Thanks Paul. Hopefully Google will see the benefit they can provide advertisers by making such a feature available. Peter, I agree the use of negatives can help to segment traffic to different targets, but my point is that it is difficult to use them to move traffic for a product from a less granular target to a more granular target. This is because we're not talking about 'junk terms,' but instead are talking about all of the different queries that can trigger a product to show. So if the iPhone 5s product ID is being triggered by the term 'cell phone' and performing well with it, that's fine, we just don't want that product to be shown through another, less granular target for that query as it then nullifies the bid that we have assigned the product ID as what we are willing to pay for that product to show. Further, most of our clients have many levels of granularity to their PLA targeting, not just a catchall and everything else, with different negatives applied to different levels. Thus, simply adding all negatives to everything but All Products is not optimal.
Peter Humleker says:
I think I was misunderstood. We don't set up just 2 campaigns, one catchall and the other everything else. We create an Ad Group for each individual product. So if a client has 3000 products we do an ad group for each product. That is as granular as you can possibly get. We also do an individual bid for every single product. Again, as granular as you can get... So therefore when I do a Auto Target > See Search Terms > All report I can see exactly what exact product was shown for each search query. Then I can create negative keywords and manage which products show for which terms. However yes I agree it would be nice if Google provided a way to add negative product id's. It would create a lot less work doing the search query management! :-) Great article by the way Andy!
Thanks Peter. Sorry for the misunderstanding. The search term reports are definitely a good way to see what queries are triggering each product ID, but Google sadly has no reporting feature available to see what product was served for a specific query through a broader target, such as All Products. Just another feature that Google could provide to help advertisers. Thanks for reading and the great input!
Cathy N says:
Hi Andy, You mentioned in your post: "For example, a Product ID target for one advertiser was launched with a bid that was 85% higher than the All Products target, yet Google ignored the more granular target and instead sent hundreds of clicks a week to the All Products target." Can I ask - How were you able to see traffic for an individual product within your All target?
Hi Cathy, Great question. We use a redirect for tracking which captures the final destination of a click as well as which target it was associated to. Thus, I can figure out which products are getting the traffic within any target.


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