A linear attribution model aims to divide each ad interaction in the user path evenly, as if the contribution of each ad impression and each click, regardless of the medium or the context of the advertising, was evenly spread. Linear attribution models are some of the most uncommon attribution models, given the limitations and flaws these posses:

• With diminishing access to user level data, collecting ad interaction data is mostly blocked by browsers
• Advertisers operating on offline channels will not be able to include those ad interaction data points
• Different mediums (Search, Social, TV..) have vastly different impact and impact curves