A city conducted a traffic study. It reported that having more signals does not indicate a shorter or longer commute time for drivers. What can be determined? There is no correlation between number of signals and commute time. There is a correlation between number of signals and commute time. However, there is no causation. This is because there is probably an increase in the commute time with an increase in the number of signals. There is a correlation between number of signals and commute time. There may or may not be causation. Further studies would have to be done to determine this.