                This court has jurisdiction to consider this appeal
                              As an initial matter, Gold Coast argues that this court lacks
                jurisdiction to hear this appeal because Clark did not timely file the notice
                of appeal. Because Clark's motion for reconsideration was filed within ten
                days of Clark receiving notice of the entry of judgment, the motion is
                properly treated as a Rule 59 motion that tolls the time to appeal. See AA
                Primo Builders, L.L.C. v. Washington, 126 Nev.           „ 245 P.3d 1190,
                1194-95 (2010) (treating a timely filed motion to reconsider as a Rule 59
                motion). Accordingly, this court has jurisdiction to hear this appeal.
                The district court did not abuse its discretion by excluding Clark's expert's
                testimony
                              Clark argues that the district court abused its discretion in
                excluding the testimony of her expert, Joseph DeMaria. This court
                reviews a district court's decision to allow expert testimony for an abuse of
                discretion.   Hallmark v. Eldridge, 124 Nev. 492, 498, 189 P.3d 646, 650
                (2008).
                              A witness may testify as an expert if (1) the witness is
                "qualified in an area of 'scientific, technical or other specialized knowledge'
                (the qualification requirement);" (2) the expert's "specialized knowledge
                must 'assist the trier of fact to understand the evidence or to determine a
                fact in issue' (the assistance requirement);" and (3) the expert's testimony
                is "limited 'to matters within the scope of [the expert's specialized]
                knowledge' (the limited scope requirement)."      Hallmark, 124 Nev. at 498,
                189 P.3d at 650 (quoting NRS 50.275).
                              Hallmark provides the following nonexhaustive list of factors
                to consider in determining whether an expert is qualified in an area of
                scientific, technical, or other specialized knowledge:   "a) formal schooling
                and academic degrees, (2) licensure, (3) employment experience, and (4)
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                practical experience and specialized training." Hallmark, 124 Nev. at 499,
                189 P.3d at 650-51.
                               DeMaria is qualified to testify as an expert in safety
                engineering, the field in which Clark proffered him. His lengthy
                curriculum vitae shows that he has a Ph.D. in occupational safety and
                health engineering, numerous certifications, and a lengthy work history
                relevant to this field. This work history includes employment as the risk
                manager of Rio Suites Hotel and Casino. Accordingly, DeMaria satisfies
                the qualification requirement of NRS 50.275. Thus, the district court
                abused its discretion by excluding DeMaria on the basis that he was
                unqualified.
                               Under the assistance requirement, an expert's opinion must be
                relevant and the product of a reliable methodology. Hallmark, 124 Nev. at
                500, 189 P.3d at 651. To determine whether an expert's opinion is based
                upon reliable methodology, "a district court should consider whether the
                opinion is (1) within a recognized field of expertise; (2) testable and has
                been tested; (3) published and subjected to peer review; (4) generally
                accepted in the scientific community . . . ; and (5) based more on
                particularized facts rather than assumption, conjecture,                   Or

                generalization." Id. at 500-01, 189 P.3d at 651-52. "[T]hese factors are not
                exhaustive, may be accorded varying weights, and may not apply equally
                in every case." Id. at 502, 189 P.3d at 652.
                               In the present case, DeMaria's opinion was that the applicable
                safety standard requires the escalator to come to a gradual stop, while
                here the escalator came to a sudden stop. According to DeMaria, that
                standard requires an escalator to stop within a maximum of three seconds.
                The standard does not mention a minimum stopping time. Gold Coast's

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                 expert stated in his report that the escalator is designed to stop quickly
                 when the safety switch is activated in order to prevent injury if a person is
                 caught in the machinery. DeMaria did not provide a basis for determining
                 how fast the escalator in question actually stopped besides a guestimate
                 from watching the surveillance video. Furthermore, he did not offer an
                 opinion on the correct stopping• time (much less a methodology for
                 calculating a non-negligent stopping time), and he did not provide any
                 explanation for the relative risk involved between a sudden stop and a
                 gradual stop. Because DeMaria's opinion is not based on any recognized
                 methodology, the district court did not abuse its discretion in striking
                 DeMaria as an expert after concluding that DeMaria's opinion "is not of an
                 expert nature."    See Hallmark, 124 Nev. at 500-01, 189 P.3d at 651.
                             Because the district court did not abuse its discretion in
                 concluding that DeMaria's opinion did not satisfy the assistance
                 requirement, we affirm the district court's decision to exclude DeMaria's
                 testimony. See Hotel Riviera, Inc. v. Torres, 97 Nev. 399, 403, 632 P.2d
                 1155, 1158 (1981) ("If a decision below is correct, it will not be disturbed
                 on appeal even though the lower court relied upon wrong reasons.").
                 Res ipsa loquitur is inapplicable
                             Clark next argues that the doctrine of res ipsa loquitur allows
                 her to raise an inference of negligence without expert testimony. We
                 conclude that the doctrine of res ipsa loquitur is inapplicable.
                             An inference of negligence may be raised where the plaintiff
                 shows (1) the defendant was in exclusive control of the instrumentality
                 causing injury, (2) the accident causing injury does not ordinarily happen
                 in the absence of negligence, and (3) the defendant is in a better position
                 than the plaintiff to explain the cause of the accident.   Otis Elevator Co. v.
                 Reid, 101 Nev. 515, 519, 706 P.2d 1378, 1380 (1985).
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                              Other jurisdictions have held that       res ipsa loquitur is
                inappropriate in similar escalator-related cases because a plaintiff cannot
                show exclusive control where the machine was subject to extensive public
                contact or because applying the doctrine would make the owner the
                insurer of all who use the escalator. See, e.g., Parris v. Port of N.Y. Auth.,
                850 N.Y.S.2d 53, 54-55 (App. Div. 2008); Tinder v. Nordstrom, inc., 929
                P.2d 1209, 1213-14 (Wash. Ct. App. 1997). Other jurisdictions have also
                held that expert testimony is required to establish that sudden escalator
                stoppage was caused by negligence and thus the doctrine of res ipsa
                loquitur is inapplicable. See, e.g., Holzhauer v. Saks Si Co., 697 A.2d 89,
                95 (Md. 1997). We find the reasoning of these cases persuasive and
                conclude that the facts of this case do not permit an inference of
                negligence in Clark's favor.
                The district court did not abuse its discretion by denying Clark's motion to
                extend discovery
                              Next, Clark argues that the district court abused its discretion
                by denying her motion to extend discovery because she satisfied her
                burden of showing excusable neglect. The phrase "excusable neglect," as
                used in the applicable local rule, EDCR 2.35, has not been defined by this
                court.
                              This court reviews a district court's decision on discovery
                matters for an abuse of discretion. Club Vista Fin. Servs., L.L.C. v. Eighth
                Judicial Dist. Court, 128 Nev. „ 276 P.3d 246, 249 (2012). This
                court reviews de novo the district court's legal conclusions regarding court
                rules. Casey v. Wells Fargo Bank, N.A., 128 Nev. , , 290 P.3d 265,
                267 (2012).
                              EDCR 2.35(a) provides that a request for additional time for
                discovery made later than 20 days from the close of discovery "shall not be
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                 granted unless the moving party, attorney or other person demonstrates
                 that the failure to act was the result of excusable neglect." The meaning of
                 the term excusable neglect appears well settled. For example, Black's Law
                 Dictionary defines "excusable neglect" as• follows:
                             A failure which the law will excuse—to take
                             some proper step at the proper time (esp. in
                             neglecting to answer a lawsuit) not because of the
                             party's own carelessness, inattention, or willful
                             disregard of the court's process, but because of
                             some unexpected or unavoidable hindrance or
                             accident or because of reliance on the care and
                             vigilance of the party's counsel or on a promise
                             made by the adverse party.
                 Black's Law Dictionary 1133 (9th ed. 2009). A number of Nevada cases
                 have applied "excusable neglect" as grounds for enlarging time under
                 NRCP 6(b)(2) and as a basis for setting aside a judgment under NRCP
                 60(b)(1). The concept of "excusable neglect" does not apply to a party
                 losing a fully briefed and argued motion; instead, the concept applies to
                 instances where some external factor beyond a party's control affects the
                 party's ability to act or respond as otherwise required. See, e.g., Moseley v.
                 Eighth Judicial Dist. Court, 124 Nev. 654, 667-68, 188 P.3d 1136, 1145-46
                 (2008) (concluding that, under NRCP 6(b)(2), excusable neglect may justify
                 an enlargement of time to allow for substitution of a deceased party where
                 the delay was caused by a lack of cooperation from the decedent's family
                 and attorney); Stoecklein v. Johnson Elec., Inc., 109 Nev. 268, 273, 849
                 P.2d 305, 308 (1993) (affirming a district court's finding of excusable
                 neglect under NRCP 60(b)(1) where default judgment resulted from a lack
                 of notice); Yochum v. Davis, 98 Nev. 484, 486-87, 653 P.2d 1215, 1216-17
                 (1982) (reversing a district court's order denying a motion to set aside a



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                       default judgment under NRCP 60(b)(1) where default resulted from a lack
                       of procedural knowledge).
                                    In the present case, the district court entered its order striking
                       DeMaria as an expert witness in June 2012, after briefing by both parties
                       and a hearing. Clark filed her motion in July 2012, over three months
                       after discovery closed, seeking additional time to secure a new expert
                       witness. Clark argues that `Where was no way for Ms. Clark's attorneys
                       to have foreseen the district court going so far afield of the rules for
                       admissibility of experts in premises liability." The notion that one would
                       need an expert with specialized knowledge of escalators in such a case is
                       not unusual or novel, however, and allowing a party to reopen discovery
                       upon losing a motion to strike or a motion in limine would unnecessarily
                       burden the timely and efficient resolution of litigation. Accordingly, we
                       conclude that "excusable neglect" as used in EDRC 2.35(a) does not
                       include circumstances where a party loses a fully briefed and argued
                       motion on its merits. Accordingly, we affirm the district court's order
                       adopting the discovery commissioner's finding refusing to reopen
                       discovery.
                       The district court did not abuse its discretion by denying Clark leave to file
                       an amended complaint to add Otis Elevator Company as a defendant
                                    Last, we reject Clark's argument that the district court abused
                       its discretion by denying Clark leave to file an amended complaint to add
                       Otis Elevator Company, d.b.a. Nevada Elevator Company (Otis) as a
                       defendant. Although NRCP 15(a) provides that leave to amend "shall be
                       freely given when justice so requires," leave to amend is not appropriate in
                       the face of "undue delay, bad faith or dilatory motive." Stephens v. S. Nev.
                       Music Co., 89 Nev. 104, 105-06, 507 P.2d 138, 139 (1973). NRCP 10(a)
                       allows a party to designate an unknown defendant and later amend the
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                     pleadings once the name of the defendant becomes known. NRCP 15(c)
                     allows amended pleadings to relate back to the time the original complaint
                     was filed in certain circumstances.
                                 We have held that amending a complaint under Rule 10(a)
                     requires that the party (1) plead a fictitious or Doe defendant in the
                     caption of the original complaint; (2) plead the basis for naming
                     defendants by other than their true identity, and clearly specify the
                     connection between the intended defendants and the conduct, activity, or
                     omission upon which the cause of action is based; and (3) exercise
                     reasonable diligence in ascertaining the identity of the intended
                     defendants and promptly move to amend the complaint.             Nurenberger
                     Hercules-Werke GMBH v. Virostek, 107 Nev. 873, 881, 822 P.2d 1100, 1106
                     (1991).
                                 Although the complaint contains Doe defendants in the
                     caption, the body of the complaint only mentions the Doe defendants in a
                     vague and cursory manner, without any mention of an entity responsible
                     for maintenance or operation of the escalator.' Gold Coast avers that it
                     produced the maintenance agreement between Otis and Gold Coast in
                     June 2010, while the motion for leave to file an amended complaint was
                     not filed until December 2011.
                                 Clark acknowledges Gold Coast's argument that she waited
                     well over a year to seek leave to file an amended complaint but does not
                     actually address it. Instead, she argues that the statute of limitations had


                            'Clark argues that she made allegations against the installer or
                     repairer of the escalator, but the actual complaint only names Gold Coast
                     as said installer and repairer, and does not relate the installation or repair
                     of the escalator to any mention of Doe or fictitious defendants.


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                 not yet run, thus there could not be any undue delay or lack of diligence.
                 This argument is circular, and adopting Clark's reasoning here would
                 undermine the purpose for having a timeliness requirement for adding a
                 Doe defendant outside of the statute of limitations itself.
                             Clark also argues that because Otis was indemnifying Gold
                 Coast, Otis had notice of the action. Although notice is relevant for
                 determining whether a pleading may relate back, Costello v. Casler, 127
                 Nev. 254 P.3d 631, 634 (2011), it is not a relevant factor in
                 determining whether a new defendant may be named in place of a Doe
                 defendant under NRCP 10. See Nurenberger, 107 Nev. at 881, 822 P.2d at
                 1106. Instead, we conclude that because Clark did not attempt to amend
                 the complaint until over a year after Otis's identity had been disclosed, the
                 circumstances of this case fall clearly outside of the factors set forth in
                 Nurenberger, and thus the district court did not abuse its discretion by
                 denying Clark's motion to file an amended complaint. 2 See Holcomb
                 Condo. Homeowners' Assoc., Inc. v. Stewart Venture, L.L.C.,     129 Nev. ,
                    , 300 P.3d 124, 130-31 (2013) (providing that "this court will not
                 disturb a trial court's denial of leave to amend absent an abuse of
                 discretion"). Accordingly, we



                 2 We conclude that Clark waived her argument that Gold Coast did not
                 timely file its motion for summary judgment. See Thomas v. Hardwick,
                 126 Nev. 142, 158-59, 231 P.3d 1111, 1121 (2010) (concluding that where a
                 party raises an issue for the first time on a motion for reconsideration, and
                 the trial court does not address the merits of the motion, the issue is
                 waived). For the same reasons, we also conclude that Clark waived her
                 argument that she did not need an expert based on her theory that Gold
                 Coast had a nondelegable duty to operate the escalator safely and that the
                 sudden stop was unreasonably dangerous. See id.


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                            ORDER the judgment of the district court AFFIRMED.



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                 cc:   Hon. Michael Villani, District Judge
                       William C. Turner, Settlement Judge
                       Christensen Law Offices, LLC
                       Rogers, Mastrangelo, Carvalho & Mitchell, Ltd.
                       Eighth District Court Clerk




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