What do trend lines represent in Tableau visualizations?

Trend lines in Tableau visualizations depict the pattern and direction of data trends over a specified range. They are used to reveal underlying relationships in the data by showing how values change over time or in relation to other variables.

By adding a trend line to a chart, users can easily identify whether a particular variable is increasing, decreasing, or remaining stable, which provides valuable insights into the data's trajectory. Trend lines can also assist in forecasting future values based on past behavior, making them instrumental in decision-making processes.

The other options relate to different data analysis concepts. For instance, arranging data in sequential order refers to sorting, which aligns more with data organization techniques. The average value of a dataset over time is related to measures of central tendency rather than trends. Lastly, a statistical comparison between two variables points towards correlation or regression analysis but does not specifically capture the notion of observing trends in data visually.