The board of directors of the Westville Community Center is interested in obtaining feedback from its donor base about various programmatic initiatives the center is contemplating. The board has hired a consultant to develop a survey instrument that will be sent to a random sample of 300 individuals in the donor base.

The consultant points to emerging research that finds that individuals who receive surveys via expedited delivery methods (such as next day delivery service) tend to complete surveys at a higher rate than individuals who receive surveys via traditional bulk-rate mail service (the standard way the Center has always administered surveys). The board is intrigued by this idea, but the board members want more evidence on how the expedited delivery methods would actually affect their donor base. Accordingly, the consultant devises an experiment. Th e survey is sent via expedited delivery to half of the individuals in the sample selected at random; the remaining 150 surveys are sent via bulk mail. A month after the survey has been sent, the consultant assembles a cross-tabulation on method of delivery and response rates. The data are coded as follows: 

Delivery method

1 = survey sent using expedited service

0 = survey sent using standard delivery method

Response

1 = returned completed survey

0 = did not return survey

Based on the cross-tabulation, what can the consultant tell the board about the results of the experiment?