What is the test for negligence in Section 7 of the Civil Rights Act?

"The section does not define negligence, leaving that question to be determined ... `by the common law principles as established and applied in the federal courts.' ... What constitutes negligence for the statute's purposes is a federal question, not varying in accordance with the differing conceptions of negligence applicable under state and local laws for other purposes. Federal decisional law formulating and applying the concept governs." (Urie v. Thompson (1949) 337 U.S. 163, 174, 69 S.Ct. 1018, 93 L.Ed. 1282.)