Radix tokens will have an initial short pegged period ($1 = 1 RDX) after which the token will be allowed to float free. As demand for the currency increases, the total circulation of Radix low-volatile coin will also be increased.
If demand reduces, the system has a few mechanisms in place to burn tokens in circulation as well. If these systems fail, the currency will decrease in value, in real terms, against other currencies (such as the dollar), until demand regains.
The full details of this system will be outlined in the upcoming economics white paper.