Before revision:  This relation is used to obtain the ion-preferential coefficients, which shows that ion-RNA interactions can be quantitatively measured in single molecule experiments . Our simulations predict a plausible link between the stability of the 5^{\prime} hairpin and efficiency of PRF .
After revision:  This relation is used to obtain the ion-preferential coefficients, which shows that ion-RNA interactions can be quantitatively measured in single molecule experiments , as done previously for DNA hairpins. A by product of our work is the suggestion that the frameshift efficiency is likely determined by the stability of the 5^{\prime} hairpin and efficiency of PRF .