The article “Structural Performance of Rounded Dovetail Connections Under Different Loading Conditions” (T. Tannert, H. Prion, and F. Lam, Can J Civ Eng. 2007:1600–1605) describes a study of the deformation properties of dovetail joints. In one experiment, 10 rounded dovetail connections and 10 double rounded dovetail connections were loaded until failure. The rounded connections had an average load at failure of 8.27 kN with a standard deviation of 0.62 kN. The double-rounded connections had an average load at failure of 6.11 kN with a standard deviation of 1.31 kN. Can you conclude that the mean load at failure is greater for rounded connections than for double-rounded connections?
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