So how big is the mouse pointer?
In the research of creating a design standard for touch applications, the size of the average finger pad comes up as an important figure (1cm x 1cm)
But what about the interaction method we have been using for years... the mouse pointer... How big is it?
Some say 48x48, 32x32 or 16x16. These are all in pixels, a size that depends on the pixel density. But of course, if the pixel density changes, the pixel-sized-controls we are supposed to interact with changes as well.
Is this the reason why no one writes about the size? - Because the mouse pointer is a variable compared to our finger pads? In that case, what size is the optimal size?
The physical size of a touchscreen controls do matter since you can't shrink down your fingers, however the physical size of the mouse pointer is not very relevant, as long as the pointer is not too small to be difficult to see, it will work well. Although one could argue that pointers that is too big will be aesthetically disturbing. A more useful comparison is the size of the actual mouse itself, it will depend on habit and hand size; I know people who preferred laptop mouse size since they have smaller hands while I'm most comfortable with the regular sized mouse.
what's important here is the detection area of the target, not the size of the pointing device, although the research I've seen suggests that the size of the pointing device becomes important when it = some ratio of the detectable area of the target.
Simply put, mouse pointer size doesn't matter very much besides personal preference.
A finger is only as accurate as it is big. A mouse pointer is always accurate to one pixel even if the display icon for it is larger than that. So the issue of size when talking about a mouse isn't nearly as critical as it is for touch.