I am dealing with temperature data that are measured in different distances away from the forest edge (0m, 10m,30m,50m,80m) and I would like to find out whether the temperature will drop as the distance away from the edge increases. I tried to use geom_point to plot the temperature with respect to the distance, however, the x axis value are not labelled as 0m, 10m,30m,50m and 80m, may I ask how to change it?
Also I would like to ask is it appropriate to run correlation using temperature and distance from the edge to show that they are negatively correlated in this situation? I saw correlation should be based on two continuous variable, but the distances from the edge are discrete variable, so should I just present the result using boxplot? Or is computing regression appropriate in this case?