5.7
Effective Frequency vs Recency
Two opposed rules for scheduling the same budget: buy enough repetition to cross a threshold, or spread continuous light coverage so an ad is present close to the purchase.
Effective frequency from Michael Naples (1979); recency planning from Erwin Ephron (1997), building on John Philip Jones' single-source work
What it does
Converts a budget into a schedule, which is the decision media planning actually makes. The two rules produce different plans from the same money. One concentrates weight on fewer people; the other buys presence across more weeks. Holding them against each other forces a planner to state what they believe about how the ad works.
When it breaks
Both break when treated as constants. The three-exposure threshold was a summary of the evidence available in 1979 and has never held as a universal number; recency assumes buying is continuous and randomly timed, which fails in seasonal and considered-purchase categories where there is a window and it is knowable. The deeper problem is that the two rules are not reconcilable. A planner citing whichever one supports the plan already chosen is using neither.
Case
Ephron argued from single-source data that the first exposure does most of the work and that what matters is being present near the purchase occasion, directly against the effective-frequency doctrine that had governed media buying for two decades. The dispute was never resolved empirically; both rules remain in active use.
Recency & receptivity · marketing lessons from Erwin Ephron ↗In the wild
Unchecked · not part of the tier
What people have written about this tool in the last twelve months. A machine found these and nobody has read them. Everything above this line was checked by hand.
Loading…