http://www.geocities.com/terra1024/stars1.jpg http://www.geocities.com/terra1024/stars2.jpg It seems likely to me that these are service stars, but... if they are, then why are the sizes different? What is the significance of it? The ribbons in stars1.jpg are a Philippine Liberation Medal and a Korean Service Medal. stars2.jpg is a Asiatic-Pacific Campaign Medal.
Perhaps different manufacturers. And there are two sizes of the Campaign Star devices. One for regular size medals and ribbons and one for the miniature sized medals.
Normal medal ribbon size is the same width as a ribbon (a ribbon can be representative of a medal). Miniature medals represent normal size medals, have no ribbon of the same width and are worn on the tuxedo jacket of mess dress.
Campaign stars ya get one for every campaign in that theatre ya served in... like On my Southwest asian victory medal I have 3 campaign stars..
It was mentioned here too http://www.ww2f.com/information-requests/24201-bronze-star-ribbon-question.html