3.1.2. Data Sources

This study covered nine provinces in the Yellow River Basin from 2010 to 2019. In the establishment of the index system of this paper, the actual operability and feasibility were considered. Thus, the statistical data from government departments were selected. The original data were from the "China Tourism Statistical Yearbook", the "China Energy Statistical Yearbook", the "China Transportation Statistical Yearbook", the EPS database, the provincial statistical yearbook, and the social and economic development bulletin. In this paper, data with inconsistent accounting ranges in different years were processed, and some missing data were supplemented and improved by third-order moving average.

The "bottom-up" method was used to calculate the carbon emissions in advance for the undesired output data of tourism's carbon emission efficiency (TCEE). The "bottomup" carbon emission calculation method is based on the six elements of tourism, such as tourism transportation, tourism accommodation, and tourism activities. It is actually the best choice for the carbon emission calculation, according to the actual situation in China, and this method has been widely used in the tourism field in China. Because China has yet to establish a dedicated database of carbon accounts for tourism satellites, much of the data are not available. Therefore, the "bottom-up" carbon emission calculation is more reasonable and effective. The data measured by the symbiotic interaction model come from the evaluation results of tourism's carbon emission efficiency (TCEE) and the tourism economy's high-quality development (TEHQD).
