But the average Japanese does not own a car (as an individual). I don't have the figures but someone told me that less than half of those of driving age do not own a car, moreso, of those who do have a license, a relatively small percentage of those with licenses own their own car, many are paper drivers.

It makes use of two new reddening-free concepts: a distance indicator called pseudomagnitude, and a quasi-experimental observable that is independent of distance and specific to each star, called the differential surface brightness (DSB).

The scientists repeated the experiment in order to confirm the result.

As usual, it is simpler to begin by looking at a more general setting—in this case, commutative rings—before getting involved with polynomial rings. It turns out that the nature of the ideals in a commutative ring is important: for example, we have already seen that gcd's exist in PIDs, while this may not be true in other commutative rings.