| Name | Type | Description | Notes |
|---|---|---|---|
| alternative_subject | string | The alternate email subject line to use for A/B testing. | |
| test_size | int | The percentage of contact recipients to participate in the A/B Test. For example, if the value is 30, then 30% of contacts will receive the email campaign with subject line A, and 30% of contacts will receive the email campaign with subject line B. Valid values include <code>5</code> to <code>50</code> percent. Currently, A/B tests support subject line only. | |
| winner_wait_duration | int | The number of hours Constant Contact waits after the A/B test is sent before determining the winning subject line. The winner is the subject line with the highest number of contact opens. Valid values include <code>6</code>, <code>12</code>, <code>24</code>, and <code>48</code>. After the winner is determined, Constant Contact automatically sends the email campaign with the winning subject line to all the remaining contacts, which did not participate in the A/B test. |