Digital Marketing and Social Media
This domain tests channel economics, funnel metrics and measurement honesty. Questions give a campaign table and ask what it proves, what it costs, or what to do next.
Core metrics
- Funnel: impression → click → landing → conversion → repeat purchase.
- CPC = spend ÷ clicks; CPM = spend ÷ (impressions/1,000); CPA = spend ÷ conversions; conversion rate = conversions ÷ clicks.
- ROAS = revenue ÷ media spend. CAC = spend ÷ new customers. LTV is the discounted margin stream from a customer.
- Organic reach is not guaranteed; on most social platforms paid amplification is needed for scale. Engagement rate = engagements ÷ reach.
Measurement discipline
- Last-click attribution over-credits search and branded terms; first-click over-credits awareness. Neither shows incrementality, which needs holdout or geo-lift tests.
- Privacy regimes (consent requirements, cookie restrictions, app tracking prompts) degrade cross-site tracking - plan for modelled and first-party data.
- SEO splits into technical, on-page and off-page; paid search bids interact with Quality Score, so relevance lowers CPC.
Worked example
Spend £20,000, 2,000 clicks, 100 orders, revenue £30,000. CPC = £10; conversion rate = 5%; CPA = £200; ROAS = 1.5. But average order value is £300 at 40% gross margin, so contribution per order is £120 - below the £200 CPA. The campaign loses £80 per order. Fixes: raise AOV through bundles, cut CPA via better landing-page conversion, or target higher-margin lines.
Traps
- Presenting ROAS as profit; ROAS ignores margin and fulfilment cost.
- Counting clicks or impressions as people (frequency and duplication are lost).
- Letting branded search cannibalise credit for sales that would have happened anyway.