The formula is proved for precompact sets M of weakly compact operators on a Banach space. Here ϱ(M) is the joint spectral radius (the Rota-Strang radius), is the Hausdorff spectral radius (connected with the Hausdorff measure of noncompactness) and r(M) is the Berger-Wang radius.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-sm149-1-2, author = {Victor S. Shulman and Yuri\u\i\ V. Turovskii}, title = {Formulae for joint spectral radii of sets of operators}, journal = {Studia Mathematica}, volume = {151}, year = {2002}, pages = {23-37}, zbl = {1016.47006}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-sm149-1-2} }
Victor S. Shulman; Yuriĭ V. Turovskii. Formulae for joint spectral radii of sets of operators. Studia Mathematica, Tome 151 (2002) pp. 23-37. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-sm149-1-2/