Let X be an infinite-dimensional Banach space. The measure of solvability ν(I) of the identity operator I is equal to 1.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-ba52-2-8, author = {D. Caponetti and G. Trombetta}, title = {A Note on the Measure of Solvability}, journal = {Bulletin of the Polish Academy of Sciences. Mathematics}, volume = {52}, year = {2004}, pages = {179-183}, zbl = {1115.47041}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ba52-2-8} }
D. Caponetti; G. Trombetta. A Note on the Measure of Solvability. Bulletin of the Polish Academy of Sciences. Mathematics, Tome 52 (2004) pp. 179-183. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ba52-2-8/