Uncorrected vision is prevalent among rural children and those who migrate from rural areas to urban areas with their parents in China, of which more than 20 per cent are nearsighted. Since 2012 the Rural Education Action Program (REAP) has carried out the largest empirical vision care project...

About 500 million to 1 billion poor people in the world need eyeglasses but do not get them. Visual impairment is more than just a health problem; it has economic, educational, and public safety implications. In 2005, the French multinational Essilor launched a 'bottom of the pyramid' initiative...

I examine online and offline prices for popular disposable contact lenses. Idiosyncratic features of this market make it likely that offline firms set prices on the assumption that most of their customers are unaware of online prices. Consistent with lower online search costs, offline prices are...

Die Marke Fielmann kennt heute jeder und Günther Fielmann selbst dürfte einer der bekanntesten Schleswig-Holsteiner sein. Das Buch porträtiert den erfolgreichen Unternehmer und zeichnet die Firmengeschichte vom ersten Optikerladen in Cuxhaven bis zum Markt bestimmenden Konzern nach. Die...

I use an original dataset on the display inventories of several hundred eyewear retailers to study how firms' product-range choices depend on separation from rivals in geographically-differentiated markets. A two-stage estimation approach is used to model firms' initial location decisions and...