Three psychologists performed the following experiment. They had groups of people ranging in size from just one person to as many as fifteen people stand on a street corner and stare up into the sky. They then observed how many passersby stopped and also looked up at the sky. They found that with only one person looking up, very few passersby stopped. If five people were staring up into the sky, then more passersby stopped, but most still ignored them. Finally, with fifteen people looking up, they found that 45 percent of passersby stopped and also stared up into the sky. How could you use the idea of an information cascade to explain this result?