From Powers v. Union Pac. RR, 2009 U.S. Dist. LEXIS 22131 (E.D. Tex. Mar. 19, 2008):

Trial courts are charged with the responsibility of acting as the gatekeepers of expert testimony. ***

[Footnote 3] This being said, "the trial court's role as gatekeeper is not intended to serve as a replacement for the adversary system." See United States v. 14.38 Acres of Land Situated in Leflore County, Mississippi, 80 F.3d 1074, 1078 (5th Cir. 1996). "'Vigorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof are the traditional and appropriate means of attacking shaky but admissible evidence.'" Id. (quoting Daubert, 509 U.S at 596). "[T]he district court should approach its task 'with proper deference to the jury's role as the arbiter of disputes between conflicting opinions.'" Id. at 1077.

The first [Rule 702] requirement of the reliability inquiry is one of sufficiency, inquiring whether the expert's testimony is grounded upon sufficient facts and data. This consideration is quantitative rather than qualitative in nature. ***

The second and third prongs of the reliability inquiry are qualitative in nature, requiring that the principles and methods be both reliable in and of themselves and reliably applied to the facts of the case. Courts have considered various factors as indicators of whether these two requirements have been satisfied:

(1) whether the theory or technique underlying the expert's testimony can be or has been tested;

(2) whether the theory or technique has been subject to peer review and publication;

(3) the technique's known or potential rate of error and the existence and maintenance of standards and controls;

(4) whether the theory or technique is generally accepted in the relevant field of expertise;

(5) whether the theory or technique was developed independent of or expressly for the purpose of litigation;

(6) whether the expert has unjustifiably extrapolated from an accepted premise to an unfounded conclusion;

(7) whether the expert has adequately accounted for obvious alternative explanations;

(8) whether the expert has utilized a standard of care comporting with the standard generally required by the field of expertise; and

(9) whether the field of expertise is known to reach reliable results.

[Citations omitted.]

The above referenced list of factors is not exclusive and all factors do not apply in every case.