Small-Merchant Solutions: Nine Tips for Using the Merge/Purge

Contacting customers with a direct mail piece, such as a catalog, requires data processing. Data processing can be as simple as 1) deciding that you want to mail anyone who made a purchase from your company in 2006; 2) selecting the customers’ names and addresses from your computer system; and 3) printing the mailing information on peel-and-stick address labels. Not very complex, but definitely doable in three easy steps.

Using a data processing service to prepare your mailings provides several advantages, however. From identifying duplicate records to revealing unique buyers within the same household, the opportunity to cultivate information from the data becomes more accessible. This accessibility gives you insight into segmenting the customers you want to mail and better identifying those you want to omit from the mailing.

Preparing for a mailing usually includes sending the data processing provider all the lists to be evaluated and considered for the mailing. Examples include customer records, catalog requestors, inquiries, sweepstake entrants, rented names, and suppression files. Along with the records, you will send “the list of lists,” a document of every list segment and its corresponding identifiers such as list name, list description, quantity, keycode, list ID, family ID, and merge hierarchy and instructions. Each element has an important role as you decide who will receive the mailing. Thus begins the merge/purge.

In its basic form, the merge/purge is the process of merging all lists together and purging duplicates. And in doing so, however, you can gain additional data insights to help with audience segmentation. Here are the type of data to look for and how to use them.

  1. Descending order

    Providing the data in a hierarchy from most important to least important is one of the simplest ways to visually recognize data. Particularly helpful to companies that cannot send unique records by customer segment, the merge/purge will omit duplicates while retaining the record highest in the priority. What do we mean by that? Assume that there are 2,000 records in the 2007 customer group, which you’ve designated as hierarchy 1, and 10,000 records in the 2006 customer group, assigned as hierarchy 2. After the merge/purge, the 1,500 duplicates between hierarchy 1 and 2 will be removed from the hierarchy 2 group and retained in group 1. Now you’ll have a clear picture of the 1,500 customers who made an additional purchase from 2006 to 2007.

  2. Family IDs

    Another way to reveal interaction among lists is to assign family IDs with like segments. Most of the time, family IDs help identify and omit internal duplicates from the file. When you assign the 2007, 2006, and 2005 buyers the same family ID, for instance, the duplicates will drop, and one instance of the record will be retained with the highest list in the hierarchy (in this case, the 2007 buyers).

    If you use family IDs with rented lists, each list rental is usually assigned its own family ID to create multibuyers. If all list rentals had the same family ID, then duplicates would be omitted instead of recognized as a multis among the various lists.

    Granted, there are times when you may want to group some lists within the same family ID. If you don’t mail your catalog frequently, there might be a financial advantage to omitting duplicates instead of creating multis.

  3. Rental hits

    If you build the list hierarchy with your customers at the highest priority and list rentals toward the bottom, then any customers found on both the rental list and your customer file will be identified as a rental hit. Since this record is a duplicate, it will drop from the rental list and be retained with the customer segment. The identification of a rental hit alerts you to additional buying activity in the marketplace. You may choose to mail only these customers, particularly when you’re trying to reactive older customer segments, catalog requests, and sweepstakes entrants.

  4. Rental multis

    When merging lists and purging duplicates, the result — and benefit — of this interaction is most evident with rental lists. For example, if a record from a rental list is not found on your customer file but is found on two other rental files, then the record is considered a two-time (2x) multibuyer. You will mail the record from one of the lists now, and you have the opportunity to mail the record one more time in the future. (If you have assigned all the rental lists the same hierarchy placement, as is commonly done, the record will randomly remain with one of the two lists.)

    When the merge/purge is complete, the report for the rental multis is also parsed to isolate 2x, 3x, 4x, 5x, 6x, 7x, 8x, and 9x+ multis representing the original tally of duplicates. The 2x multis will account for the plurality of these dupes, and the 9x+ will be the scarcest — after all, it is less likely to find a rental name on nine or more rental lists than on just two lists.

  1. Unique household names

    Often a mailing strategy is designed to send one catalog per household. Though this is a practical strategy, it denies you the opportunity to identify additional buyers at the same address. This is particularly true with roommate situations. As you write the merge/purge instructions, ask the service bureau to look for unique names at the same household. You can then identify additional recipients to include with the mailing instead of omitting one of the records as a household duplicate.

    Reviewing data on an individual level, you can also look at gender-based first names among people sharing a last name at the same household to help identify married people (say, “John Davis” and “Amy Davis”). You can then decide if you want to mail both or only one.

  2. Maiden/married name

    Similar to the process of recognizing unique household names, identifiying a person who may be on the list under her maiden name as well as her married name is equally important as you strive to avoid mailing two catalogs to one recipient. By having the service bureau look for the maiden-now-married naming convention, you can clearly call out this type of duplication.

  3. Maximum contacts

    Each business-to-business merchant uses different criteria to determine how many catalogs to send to a single address. One way to help guide your decision is to ask to review the merge/purge results and evaluate the fields for “title” and “contact name.” As an example, if your company’s policy is to send up to five catalogs per mailing address, you might want to eliminate records without a title or a contact name. Perhaps for your situation, you may choose to add a title slug, “authorizing purchasing agent” or “school principal.” As you review the output from the merge/purge, the information can help provide options and reveal opportunities.

  4. E-mail hits

    If your internal systems are not integrated, you may not be able to identify catalog customers who also have a promotable e-mail address, information that is helpful if you are trying to manage the number of customer contacts you make via print and other media. One easy way to gain this visibility is to send the file of all e-mail customers with a promotable e-mail address to the service bureau and have it matched to the customers included with merge/purge. The objective is to have an e-mail flag identifying customers on your mailing list who have also agreed to receive promotional e-mail. This allows you to decide if you want to send these customers fewer catalogs but more e-mail messages, for instance, and if you’d like to keycode them separately.

  5. NCOA

    The National Change of Address (NCOA) processing can serve many functions. The purpose of cleansing the file and identifying any new movers focuses on the importance of mailing the catalog to each recipient’s current address. You also have the opportunity send a catalog to the old address as a prospecting opportunity. Depending upon the merchandise assortment, the demographic of the old address may be aligned with your target market. Another byproduct of NCOA processing are all the deliverability reports, which enable you to mail to addresses that might not have been deliverable exactly as they appeared on your file. NCOA can also reveal temporary addresses, such as those of “snowbirds” — northerners moving to southern states for the winter months. These part-time southerners may need a different merchandise assortment or marketing messages. As always, more information gives you more options.

Also remember that with NCOA processing, you should update your customer database, not just the names you’re mailing this particular time, with the new NCOA information. If you don’t apply the updates to your system, you will continually pay for the same NCOA changes each time you ask the data processing provider to run NCOA. One way to tell if your system has been applying the data is to review the reports indicating each record’s move date. When you regularly update your system, the move dates will be more recent; when you don’t regularly update your system, you’ll find move dates well beyond six months.

Merge/purge processing is a necessary step when preparing a mailing. The opportunity to use the results from the output can be a valuable segmentation tool. Talk with your vendor to help you develop the right instructions for the merge/purge. If you tell him what you want to do with the data, he will explain how you can access the information, as well as if there are additional costs beyond the basic merge/purge, and if the process will require more time. Most likely you already pay for the data — now use the information as a segment tool. These techniques can increase the productivity of your mail plan.


Gina Valentino is the owner of Hemisphere Marketing, a catalog consultancy based in Kansas City, MO.