The impact of climate information on milk demand: Evidence from a field experiment
通过在瑞典17家零售店进行随机田野实验，研究发现提供碳标签信息使气候认证牛奶的需求增加约6-8%，但效果仅在大超市显著且持续时间短。
It has been suggested that carbon labelling of food, on voluntary or non-voluntary basis, could reduce emissions of greenhouse gases. However, there is limited empirical evidence on the influence of such labels on consumer purchases. The purpose of this study was to investigate whether voluntary carbon labelling affects the demand for milk. A randomized field experiment was conducted in 17 retail stores in Sweden, where a sign provided consumers with qualitative information about the carbon impact of climate-certified milk. The results suggest that the sign increased the demand for the climate-certified milk by approximately 6–8%, and the result is robust to alternative model specifications. The effect is entirely driven by large stores, such as supermarkets. We find no statistically significant impact on total milk sales, and the dataset is too small to verify the consequences for other milk brands. The effect on the demand for the labelled milk is short-lived.