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 decresing while the popularity of skateboarding has increased in dramatically. Many Central plaza store owners believe that the decrease in their business is due to the number of skateboard users in the plaza. There has also been a dramatic increase in the amount of litter and vandalism throughout the plaza. Thuse, we recommend that the city prohibit skatboarding the Central Plaza. If skateboarding is prohibited here, we predit that business in Central Plaza will return to its prviously high levels."

What questions should be answered to decide whether the recommendation will have the predicted result?

In this letter, the store owners recommend the city prohibit skateboarding in the Central Plaza as they believe that skateboarding causes business shrinkage in the Central Plaza. However, several questions need to be answered to ensure the recommendation will have its merit.

First and the most important question is where is the evidence that proves skateboarding cause all these questions. Even though it should be true that the number of skateboard users in Central Plaza has increased and the number of shoppers has decreased, but no solid evidence is provided by the store owners. All the statements come from their believes. The letter also brings up the litter problem, but still, it isn't linked with skateboard users directly. The litters can come from anyone in the Central Plaza. Indeed, litters might be thrown by the store owners themselve. Proper evidence is important as it is also the support for the prediction. To support these believes, the owners should provide data about the relation between decrease of business and increase of skateboard users as well as the relation between the users and increase of litters.

Moreover, the letter comes from one store owner with several owners opinions. We are really interest in knowing where are other people's opinions? Where are the shoppers' opinions and the skateboard users' opinions? Will the shoppers enjoy watching skateboarding and thinking the store owners should improve their services? If the opinion of the shoppers is opposite to the store owners, the prohibition may bring the result to the other end of the prediction.

At the end, if the store owners' believes are true. Prohibition of skateboarding can help to elevate the business level. How long will it take? If this move will take more than two years to show improvement, it will not help the sellers in any aspects. To renew the whole Central Plaza or to arrange some activities in the plaza may give more help to the business.

In conclusion, the idea that skateboarding affects business is rational, but litter is lake of persuasive fact to support the prediction. In addition, the recommendation is only from sellers. Ignorance of the buyers' opinions, who are the other half of business, also causes the result unpredictable. The efficiency of this action should not be considered at the same time.