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Selecting a line item based on priority

Last updated on January 30, 2017

After applying business rules, targeting, and then frequency cappingUsing cookies to track the impression count of ads served and stop any given ad being shown to a single visitor more than the set number of times. to select a candidate set of line items for an impressionA single display of an ad on a web page, mobile app, or other delivery medium. See also billable impression, forecasted impressions., OpenX looks at the buying modelThe terms under which a specific inventory purchase is made, as well as the priority order in which OpenX considers a line item for selection, including 1. Guaranteed – exclusive; 2. Guaranteed – share of voice; 3. Guaranteed – volume goal; 4. Non-guaranteed – preferred access; 5. Non-guaranteed; 6. House for each line itemThe primary unit of execution for an OpenX order, which represents a specific inventory purchase and the required conditions for ad delivery. to determine the priorityIndicates which deal or line item should take precedence in the case that multiple deals or line items are eligible to serve for a given ad request. order in which they are eligible for the impression.

  1. Guaranteed - Exclusive line items have first priority.

    The goal of these line items is to fill all targeted impressions, considering schedules and frequency capping. If OpenX selects more than one of these line items as eligible for the same impression, the impression is oversold, and OpenX must use its tie-breaking logic to select the winning line item.

  2. Guaranteed - Share of Voice (SoV) line items have second priority.

    The goal of these line items is to fill a percentage of all targeted impressions, considering schedules and frequency capping. For example, a 25% SoV indicates that the line item should win approximately one in every four impressions.

    Share of Voice pie chart

    If the sum of the share of voice percentages for the eligible SoV line items is less than 100%, then it is possible for the impression to “fall through” to the next priority tier. If the sum is over 100%, the impression is oversold, and OpenX must scale down the percentages, relatively, to equal 100%.

    Line Item

    User-Entered %

    System-Calculated %

    A

    50%

    33.3333333...%
    B

    50%

    33.3333333...%
    C 50% 33.3333333...%
  3. Guaranteed - Volume GoalA setting for guaranteed line items. A volume goal for impressions is used to reach a set number of impressions as soon as possible, depending on the Priority setting for the line item. line items have third priority.

    The goal of these line items is to ensure paced-delivery of impressions over a specific date range. OpenX attempts to pace the delivery based on your configured delivery curve, and a given line item’s preference for smooth or non-smooth pacingA pacing configuration that delivers 95 percent of the goal impressions by the halfway mark for the line item's date range.. OpenX uses a real-time prioritization system to evaluate each line item’s eligibility and make quick priority adjustments based on changes in delivery or traffic patterns.

    If OpenX selects more than one of these as line items as eligible for the same impression, then the system sorts candidate line items based on their Priority (1-10, 1 is highest), Make Good setting, eCPMEffective cost per mille tells a publisher what he or she would have received if they sold advertising inventory on a CPM basis., and system-managed priority (for pacing). OpenX does not consider any other tie-breaking logic, and it is possible that a volume guarantee line item does not win a given impression, at least in cases where there is excess inventoryAd space available on a website or app. The basic unit of inventory for OpenX is an ad unit. to meet the pacing needs of each candidate line item. The line item's Priority setting is only meaningful when you expect inventory contention – that is, the impression is oversold and you want to indicate which line items will starve first (those with a lower priority). This does not mean that higher priority line items will deliver in their entirety before lower priority line items.

    For example, assume that the system-determined priority is a percentage indicating the ratio of eligible impressions that a line item must take to stay on schedule. For example, a priority of .5 means that 1 of every 2 eligible impressions must be allocated to the line item for it to remain on schedule. A priority of 1.2 indicates that a line item is behind schedule and needs more impressions than it has access to.

  4. Non-guaranteed line items have fourth priority.

    The goal of these line items is to deliver to as many targeted impressions as possible, considering frequency capping and possible impression caps. This class of line item is generally eCPM optimized to ensure maximum yield, since there is no delivery guarantee to a buyerA company that pays a demand partner to purchase ad inventory on OpenX Ad Exchange.. If OpenX selects more than one of these line items as eligible for the same impression, the system uses its tie-breaking logic to select the winning line item.

  5. House line items have last priority.

    Generally, these line items are used for internal promotions or fallback ads. Revenue calculations treat impressions given to house lines as non-billable. If OpenX selects more than one of these line items as eligible for the same impression, the system uses its tie-breaking logic to select the winning line item.

Delivery curves

For Guaranteed - Volume Goal line items, you can customize both smooth and non-smooth delivery curves at a global level. These curves tell the system how to pace line item delivery to achieve the desired delivery schedules. To make adjustments to these curves, please contact your account manager.

This topic applies to Ad Server.

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