2.3 Data analysis
We used the Mann-Whitney U test and one-way ANOVA to determine whether the presence or absence of a sample line of animal trails influenced the degree of preference for marking by pandas, based on whether the independent variables conformed to a normal distribution and the chi-squaredness of the variance; for the degree of preference for different terrain we used the Kruskal Wallis test. In addition, we used the Mann-Whitney U test as well as the chi-square test to determine whether individual variables were significantly different between the marker and control samples, and between the marked and control trees. Afterwards, we used Pearson Correlation Analysis to determine the correlation among the variables, and after eliminating the significantly correlated variables, we used stepwise regression to build the best model to determine which variable had the greatest effect on the selection of marking sites by giant pandas. In this study, we determined that the differences were statistically significant at P< 0.05 and all tests were two tailed. All data analysis was carried out in IBM SPSS Statistics 27.0.1.