For a motorist entering mall parking lots, the questions always is the same: Should I park on the fringe and walk or cruise the lot and maybe, just maybe, find that empty slot near the main entrance?
Two university assistant professors of industrial engineering finally have an answer. According to Richard Cassady of Mississippi State and John Kobza of Virginia Tech, the more aggressive driver who zooms through the parking lot in search of the close-in space may be wasting time.
Titled "A Probabilistic Approach to Evaluate Strategies for Selecting a Parking Space," their study appears in the current issue of the journal Transportation Science.
"In our study of a 'typical' lot, the more conservative driver who enters, selects a row flowing in the correct direction and enters the first available space takes an average of 61 seconds to park and walk to the front door," said Cassady.
The findings are from a study Cassady conducted while a doctoral student at Virginia Tech. It concludes that the more aggressive driver who goes from row to row in search of the closest space takes an average of 71 seconds to park and walk to the front entrance.
Cassady, who joined the MSU faculty in 1996, said the research is based on a parking lot with four entrances, seven rows with 72 spaces each, handicapped parking, employees spaces, shopping cart return locations and directional restrictions.
The project began as a discussion between Kobza and his wife about parking habits.
"I don't like to drive around in parking lots very much," Kobza said. "I tend to go in, find a spot rather quickly and walk to the store. However, because my wife doesn't like to walk a long way, we sometimes are not able to find a parking space that makes us both happy."
Cassady began the study by visiting the lot of a large discount store, counting parking spaces and measuring the lot's physical dimensions. He and Kobza then used mathematical and probability models, as well as observation of driver behavior, to complete the study.
Will their mathematical proof help change people's behavior? Probably not, Cassady admits.
"I guess if walking isn't a problem for a driver, being very conservative and taking the first available spot is probably the way to go," he said. "On the other hand, if you cycle around enough, you can usually get closer and have to walk less."
Both engineers expressed hope that, while not Earth-shattering in its implications, their study of this decades-old question can provide the basis for more detailed studies by engineers working on improved parking lot designs. And that's not all.
"This kind of information also could be incorporated into on-board (computer) information systems to help direct drivers in crowded areas, such as huge parking lots or congested urban areas," Cassady said.