The following appeared as a letter to the editor from a Central Plaza store owner."Over the past two years, the number of shoppers in Central Plaza has been steadily decreasing while the popularity of skateboarding has increased dramatically. Many Central

The author of the letter suggests that the city should prohibit skateboarding in Central Plaza so that it can promise the business returning for most of the store owners in plaza. The author proofs his idea by providing the evidence that the increasing number of the skateboarding and the decreasing number of the shoppers over the past two years. This reason looks reasonable at the first glance, however, some flaws make it unconvincing.

First of all, correlational relationship does not imply causation. It is well known that even two factors have a strong correlational relationship, it still cannot conclude that one cause the other. It is very possible to have confounding variables which influence both of the variables. In this case the author saw the growth of the skateboarding as well as the drop of the shoppers so he gets that skateboarding cause the decline of the business. However this conclusion is invalid. To provide a causation, the author can only use experimental study not through observation.

Besides, the author also mentioned that there is also a dramatic increase in the litter and vandalism throughout the plaza. But he fails to fit them to the change of business. Actually, it can be a key reason to prevent shoppers visiting the plaza. It is very possible that skateboarding people do not create litter and vandalism but business is influenced by them. So to make sure the recovering of their business, the author should consider every piece of factors which may affect their business. If he can be certain that skateboarding is the reason to prevent shopper coming, he should provide evidence that any other factors are all irrelevant.

Besides, the author suggests that if the city prohibit skateboarding in Central Plaza, shoppers will return for sure. However, this is also a kind of self-imagine. If there is a new-born business center in a more convenient area of the city or shoppers find some new places to go, it is unlikely for them to come back. If that is true, whether or not stop the skateboarding will have no change to the Central Plaza. If the author is very confident about his conclusion, he should provide the particular reason why people will return after the change of the Plaza. And why these advantages cannot be copied by any other business center.

According to all the reasons listed above. It is too early to say that prohibit skateboarding will lead guests come back. Because the author cannot proof that skateboarding is the reason for the bad business. And also, there is no evidence to support that people will come back after a two years’ leaving. To make his argument valid, the author should evaluate his evidence carefully and provide more detail to strengthen his idea.