Weather, Live Television, and the Changing Predictive Value of Demand Signals in France

ABSTRACT Managers rely on observable demand signals to forecast audiences and allocate advertising inventory, but these signals may lose value when digitalization expands the set of available substitutes. This paper asks whether daily weather remained equally informative for live television demand in France during the 2010s. Using about 24.7 million individual‐day audience observations from Médiamétrie, matched to regional daily weather data from Météo‐France over 2011–2018, we test whether the relationship between sunshine and live television viewing weakened after 2014. Before 2015, sunnier days are associated with significantly lower live television viewing. From 2015 onward, this negative relationship becomes significantly weaker. The attenuation is concentrated in live television, with smaller changes for other television‐set uses, which suggests that live television became a less exclusive indoor fallback activity as indoor substitutes expanded. For managers, historical demand relationships may therefore provide less reliable guidance for audience forecasting and inventory planning, and forecasting rules built on past regularities should be periodically revalidated.