Review the following statements about effective testing of partnership strategies for user growth and determine which statement(s) are correct:
- Statement I: A successful influencer partnership is evaluated by both the increase in brand awareness and the direct impact on sales or conversions attributed to the influencer's content.
- Statement II: When a business collaborates with another company for joint marketing efforts, the effectiveness of the partnership can be measured by analyzing cross-promotional engagement metrics and the mutual growth of customer bases.
- Statement III: In an affiliate marketing program, tracking the sales conversions from affiliate links provides a clear indicator of the program's effectiveness in driving user growth.
- Statement IV: For partnerships with niche blogs or content creators, assessing the referral traffic and its conversion rate on the brand's website helps determine the success of the collaboration.
Select the correct statement(s).