Dapatkah seseorang tolong jelaskan pembengkokan waktu dinamis untuk menentukan kesamaan deret waktu?

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Saya mencoba memahami ukuran kelengkungan waktu dinamis untuk membandingkan deret waktu bersama. Saya memiliki tiga dataset deret waktu seperti ini:

T1 <- structure(c(0.000213652387565, 0.000535045478866, 0, 0, 0.000219346347883, 
0.000359669104424, 0.000269469145783, 0.00016051364366, 0.000181950509461, 
0.000385579332948, 0.00078170803205, 0.000747244535774, 0, 0.000622858922454, 
0.000689084895259, 0.000487983408564, 0.000224744353298, 0.000416449765747, 
0.000308388157895, 0.000198906016907, 0.000179549331179, 9.06289650172e-05, 
0.000253506844685, 0.000582896161212, 0.000386473429952, 0.000179839942451, 
0, 0.000275608635737, 0.000622665006227, 0.00036075036075, 0.00029057097196, 
0.000353232073472, 0.000394710874285, 0.000207555002076, 0.000402738622634, 
0, 0.000309693403531, 0.000506521463847, 0.000226988991034, 0.000414164423276, 
9.6590360282e-05, 0.000476689865573, 0.000377572210685, 0.000378967314069, 
9.25240562546e-05, 0.000172309813044, 0.000447627573859, 0, 0.000589333071408, 
0.000191699415317, 0.000362943471554, 0.000287549122975, 0.000311688311688, 
0.000724112961622, 0.000434656621269, 0.00122292103424, 0.00177549812586, 
0.00308008213552, 0.00164338537387, 0.00176056338028, 0.00180072028812, 
0.00258939580764, 0.00217548948513, 0.00493015612161, 0.00336344416683, 
0.00422716412424, 0.00313360554553, 0.00540144648906, 0.00425728829246, 
0.0046828437633, 0.00397219463754, 0.00501656412683, 0.00492700729927, 
0.00224424911165, 0.000634696755994, 0.00120550276557, 0.00125313283208, 
0.00164551010813, 0.00143575017947, 0.00237006940918, 0.00236686390533, 
0.00420336269015, 0.00329840900272, 0.00242005185825, 0.00326554846371, 
0.006217237596, 0.0037103784586, 0.0038714672861, 0.00455830066551, 
0.00361747518783, 0.00304147465438, 0.00476801760499, 0.00569875504121, 
0.00583855136233, 0.0050566695728, 0.0042220072126, 0.00408237321963, 
0.00255222610833, 0.00123507616303, 0.00178136133508, 0.00147434637311, 
0.00126742712294, 0.00186590371937, 0.00177226406735, 0.00249154653853, 
0.00549127279859, 0.00349072202829, 0.00348027842227, 0.00229555236729, 
0.00336862367661, 0.00383477593952, 0.00273999412858, 0.00349618180145, 
0.00376108175875, 0.00383351588171, 0.00368928059028, 0.00480028982882, 
0.00388823582602, 0.00745054380406, 0.0103754506287, 0.00822677278011, 
0.00778350981989, 0.0041831792162, 0.00537228238059, 0.00723645609231, 
0.0144428396845, 0.00893333333333, 0.0106231171714, 0.0158367059652, 
0.01811729548, 0.0207095263821, 0.0211700064641, 0.017604180993, 
0.0165804327375, 0.0188679245283, 0.0191859923629, 0.0269251008595, 
0.0351239669421, 0.0283510318573, 0.0346557651212, 0.0270022042616, 
0.0260845175767, 0.0349758630112, 0.0207069247809, 0.0106362024818, 
0.00981093510475, 0.00916507201128, 0.00887198986058, 0.0073929115025, 
0.00659077291791, 0.00716191546131, 0.00942304513143, 0.0106886280007, 
0.0123527175979, 0.0171022290546, 0.0142909490656, 0.0157642220699, 
0.0265140538974, 0.0194395354708, 0.0241685144124, 0.0229897123662, 
0.017921889568, 0.0155115839714, 0.0145263157895, 0.017609281127, 
0.0157671315949, 0.0190258751903, 0.0138453217956, 0.00958058335108, 
0.0122924304507, 0.00929741151611, 0.00885235535884, 0.00509319462505, 
0.0061314863177, 0.0063104189044, 0.00729117134253, 0.010843373494, 
0.0217755443886, 0.0181687353841, 0.0155402963498, 0.017310022503, 
0.0214746959003, 0.026357827476, 0.0194751217195, 0.0196820590462, 
0.0184317400812, 0.0130208333333, 0.0128666035951, 0.0120045731707, 
0.0122374253228, 0.00874940561103, 0.0114368092263, 0.00922893718369, 
0.00479041916168, 0.00644107774653, 0.00775830595108, 0.00829578041786, 
0.00681348095875, 0.00573782551125, 0.00772002058672, 0.0112488083889, 
0.00908907291456, 0.0157722638969, 0.00994270306707, 0.0134179772039, 
0.0126050420168, 0.0113648781554, 0.0153894803415, 0.0126959699913, 
0.0116655865198, 0.0112065745237, 0.0122006737686, 0.010251878038, 
0.010891174691, 0.0148273273273, 0.0138516532618, 0.0136552722011, 
0.00986993819758, 0.0097852677358, 0.00889011089726, 0.00816723383568, 
0.00917641660931, 0.00884466556108, 0.0182179529646, 0.0183156760639, 
0.0217806648835, 0.0171099125907, 0.0186579938377, 0.019360390076, 
0.0144603654529, 0.0177730696798, 0.0153226598566, 0.0134016909516, 
0.0126480805202, 0.0115501519757, 0.0127156322248, 0.0124326204138, 
0.0240245215806, 0.0130234933606, 0.0144222706691, 0.00854005693371, 
0.0053560967445, 0.00504132231405, 0.00288778877888, 0.00593526847816, 
0.00455653279644, 0.00433014040152, 0.00535770564135, 0.0131095962244, 
0.0126319758673, 0.0154982879798, 0.0125940464508, 0.0169948745616, 
0.0257535512184, 0.0256175663312, 0.0265191262043, 0.0228974403622, 
0.0193122555411, 0.0165794768612, 0.015658837248, 0.0168208578638, 
0.0129912843282, 0.0119498443154, 0.0112663755459, 0.00838112042347, 
0.00925767186696, 0.0113408269771, 0.0210861519924, 0.0156036134684, 
0.0121687119728, 0.011006497812, 0.0107891491985, 0.0134615384615, 
0.0147229755909, 0.015756893641, 0.0176257128046, 0.016776075857, 
0.0169553999263, 0.0179193118984, 0.0190055672874, 0.0183088625509, 
0.0155489923558, 0.0152507401094, 0.0160748342567, 0.0161532350605, 
0.0139190952588, 0.0161469457497, 0.0118186629035, 0.0109259765092, 
0.00950587391265, 0.00928986154533, 0.00815520645549, 0.00702576112412, 
0.00709539362541, 0.00827287768869, 0.0104688211197, 0.0130375888927, 
0.0160891089109, 0.0188415910677, 0.0203265044814, 0.0183175033921, 
0.0139940353292, 0.0124648170487, 0.0131685758095, 0.00957428620277, 
0.0119647893342, 0.00835800104475, 0.0101892285298, 0.00904207699194, 
0.00772134522992, 0.00740740740741, 0.00776823249863, 0.00642254601227, 
0.00484237572883, 0.00361539964823, 0.00414811817078, 0.00358072916667, 
0.00433306007729, 0.00485008818342, 0.00905280804694, 0.00931847250137, 
0.00779271381259, 0.00779912497622, 0.00908230842006, 0.0058152538582, 
0.0102777777778, 0.00807537012113, 0.00648535564854, 0.0145492582731, 
0.00694127317563, 0.00759878419453, 0.00789242911429, 0.00635050701629, 
0.00785233530492, 0.00607964332759, 0.00531968282646, 0.00361944157187, 
0.00305157155935, 0.00276327909119, 0.00318820364651, 0.00184464029514, 
0.00412550211703, 0.00516567972786, 0.00463655399342, 0.00702897308418, 
0.0100714154917, 0.00791168353266, 0.00959190791768, 0.00736, 
0.00738007380074, 0.012573964497, 0.0117919562013, 0.00842919476398, 
0.00778887565289, 0.00623967700496, 0.0062232955601, 0.00447815755803, 
0.00511135450894, 0.00502557659517, 0.00330328263712), .Tsp = c(1, 
15.9583333333333, 24), class = "ts")

T2 <- structure(c(0, 0, 0, 0, 0.000109673173942, 0, 0, 0, 0, 0, 0, 
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9.66183574879e-05, 0, 
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9.43930526713e-05, 
0, 0, 0, 8.95255147717e-05, 0, 0, 0, 0, 0.000191699415317, 0.000207792207792, 
0, 0, 0, 0.00019727756954, 0.000205338809035, 0.000205423171734, 
0.000704225352113, 0.000450180072029, 0.000493218249075, 0.000120860526952, 
0.000410846343468, 0.000384393619066, 0.000643264105863, 0.000189915487608, 
0.000915499404925, 0.000185099490976, 0.000936568752661, 0.000451385754266, 
0.000757217226692, 0.000273722627737, 0.000187020759304, 0.000211565585331, 
0.000141823854772, 9.63948332369e-05, 0.000117536436295, 0.000287150035894, 
0, 0, 0.000400320256205, 0.000388048117967, 0.000345721694036, 
0.000296868042155, 0.000609533097647, 0.000424043252412, 0.000290360046458, 
0.000546996079861, 0.000556534644282, 0.00036866359447, 0.000275077938749, 
0.000964404699281, 0.00152310035539, 0.00113339145597, 0.00061570938517, 
0.000362877619523, 0.000472634464505, 0.000102923013586, 0.000187511719482, 
0.000294869274622, 0.00011522064754, 0.000248787162582, 0, 0.00035593521979, 
0.000392233771328, 0.000551166636046, 0.000165727543918, 0.000143472022956, 
0.00012030798845, 0.000438260107374, 0.000195713866327, 0.000184009568498, 
0.000537297394108, 0.000365096750639, 0.000102480016397, 0.000452857531021, 
0.000180848177955, 0.000770745910765, 0.00219818869252, 0.000357685773048, 
0.000362023712553, 0.000660501981506, 0.000419709560984, 0.000488949735967, 
0.00177758026886, 4e-04, 0.000475661962898, 0.000879816998064, 
0.0014942099365, 0.00378173960022, 0.00274725274725, 0.00192545729611, 
0.0016462841016, 0.00176238855484, 0.00260780478718, 0.00447289949132, 
0.0034435261708, 0.00290522941294, 0.002694416055, 0.0041329904482, 
0.00729244577412, 0.0296930503689, 0.00982375036117, 0.00453023439039, 
0.00327031170158, 0.00221573169503, 0.00211237853823, 0.00108719286801, 
0.00131815458358, 0.000983008004494, 0.00132253265002, 0.00227790432802, 
0.00247054351957, 0.00307455803228, 0.0029314767314, 0.00222755311857, 
0.00492610837438, 0.00454430699318, 0.00753880266075, 0.00671845475541, 
0.00590490003108, 0.00288356368698, 0.00294736842105, 0.00248601615911, 
0.00197089144936, 0.00326157860404, 0.00302866414278, 0.00202256759634, 
0.00258788009489, 0.00169043845747, 0.00137000737696, 0.000433463372345, 
0.000908368343363, 0.000805585392052, 0.00142653352354, 0.00189328743546, 
0.00558347292016, 0.00161899622234, 0.00162631008312, 0.00276960360048, 
0.00585673524553, 0.00519169329073, 0.0045125282033, 0.00562344544176, 
0.00322815786733, 0.00330528846154, 0.00255439924314, 0.00285823170732, 
0.00240894199268, 0.00218735140276, 0.00201826045171, 0.00168701002282, 
0.000460617227084, 0.00127007166833, 0.00109529025192, 0.000819336337567, 
0.00158170093685, 0.000588494924231, 0.00120089209127, 0.00305052430887, 
0.00161583518481, 0.00211579149837, 0.0010111223458, 0.00346270379455, 
0.00228091236495, 0.00207627581685, 0.00295140718878, 0.0022121765894, 
0.00240718451995, 0.00224131490474, 0.0031867431485, 0.00176756517897, 
0.00233382314807, 0.00178303303303, 0.00169794459339, 0.00162778079219, 
0.000737939304492, 0.00135906496331, 0.000733205022454, 0.000875060768109, 
0.00114705207616, 0.000967385295744, 0.00182179529646, 0.00359130903214, 
0.00420328620558, 0.00446345545843, 0.00376583361862, 0.00659687365553, 
0.00433810963586, 0.00353107344633, 0.00333955407131, 0.00341788091383, 
0.0024939877082, 0.00538428137212, 0.00906989151698, 0.00773778473309, 
0.0210421671775, 0.00859720803541, 0.00511487506289, 0.00406669377796, 
0.00117164616286, 0.00206611570248, 0.00107260726073, 0.00148381711954, 
0.000741761152909, 0.00104973100643, 0.00110305704381, 0.00209753539591, 
0.00452488687783, 0.00486574157506, 0.00850507033039, 0.0101159967629, 
0.0163991223005, 0.0150452373691, 0.0156443766097, 0.0112310639039, 
0.00635593220339, 0.00627766599598, 0.00583041812427, 0.00622371740959, 
0.00624897220852, 0.00420769166036, 0.00305676855895, 0.00291133656815, 
0.00120006857535, 0.00501806503412, 0.00490575781048, 0.00593119810202, 
0.00226874291018, 0.00304999336958, 0.00339087546239, 0.00541958041958, 
0.00445563734986, 0.00431438754455, 0.0038016243304, 0.0037928519329, 
0.00491460867428, 0.00460782305959, 0.00508734881935, 0.00300725278613, 
0.00390896455872, 0.00367811967345, 0.00953591862683, 0.00529614264278, 
0.00243584167029, 0.00427167876976, 0.00291056623743, 0.00227624510607, 
0.00439422473321, 0.00232246538633, 0.00317623830372, 0.00263466042155, 
0.00180200473026, 0.00190912562047, 0.0034896070399, 0.00338638672536, 
0.00548090523338, 0.00697836706211, 0.00720230473752, 0.00746268656716, 
0.00367056664373, 0.0032167269803, 0.00523135203391, 0.00299196443837, 
0.00299119733356, 0.00287306285913, 0.00154657933042, 0.00214861235452, 
0.00163006177076, 0.00157407407407, 0.00137086455858, 0.00124616564417, 
0.000790591955727, 0.00107484854407, 0.00121408336706, 0.00108506944444, 
0.00105398758637, 0.000881834215168, 0.00184409052808, 0.00237529691211, 
0.0013637249172, 0.00190222560396, 0.00264900662252, 0.00156564526951, 
0.00263888888889, 0.00183531139117, 0.00303347280335, 0.0120768352986, 
0.00365330167139, 0.00351443768997, 0.00263080970476, 0.0029703984431, 
0.00265143789517, 0.0014185834431, 0.00150557061126, 0.00144777662875, 
0.00111890957176, 0.000716405690308, 0.000797050911627, 0.000512400081984, 
0.000868526761481, 0.00113392969636, 0.00134609632067, 0.00240013715069, 
0.00128181651712, 0.00110395584177, 0.00156958493198, 0.00208, 
0.00184501845018, 0.00110946745562, 0.000736997262582, 0.00208250694169, 
0.00229084578026, 0.00137639933933, 0.00111462010032, 0.000822518735149, 
0.00200803212851, 0.000987166831194, 0.00041291032964), .Tsp = c(1, 
15.9583333333333, 24), class = "ts")

T3 <- structure(c(0.00192287148809, 0.00149812734082, 0.00192410475681, 
0.00151122625216, 0.00120640491336, 0.00167845582065, 0.00121261115602, 
0.000802568218299, 0.00109170305677, 0.00250626566416, 0.00273597811218, 
0.00242854474127, 0.00160915430002, 0.00124571784491, 0.00192943770673, 
0.00329388800781, 0.00191032700303, 0.00156168662155, 0.00174753289474, 
0.0014917951268, 0.00143639464943, 0.000543773790103, 0.000929525097178, 
0.00141560496294, 0.000966183574879, 0.000719359769805, 0.00190740419629, 
0.00137804317869, 0.00197177251972, 0.001443001443, 0.00203399680372, 
0.00158954433063, 0.00256562068285, 0.00228310502283, 0.00302053966975, 
0.00227352221056, 0.00263239393001, 0.00202608585539, 0.00272386789241, 
0.00269206875129, 0.0027045300879, 0.00276480122033, 0.00405890126487, 
0.00341070582662, 0.00351591413768, 0.00336004135436, 0.00358102059087, 
0.00257289879931, 0.00235733228563, 0.00239624269146, 0.00136103801833, 
0.000862647368926, 0.00145454545455, 0.00168959691045, 0.00246305418719, 
0.0020964360587, 0.00335371868219, 0.00390143737166, 0.00349219391947, 
0.00334507042254, 0.00255102040816, 0.00332922318126, 0.00386753686246, 
0.00246507806081, 0.00432442821449, 0.00312442565705, 0.00408318298357, 
0.00375354756019, 0.00416473854697, 0.00263942103023, 0.0028888688273, 
0.00321817321344, 0.00310218978102, 0.002150738732, 0.00296191819464, 
0.00134732662034, 0.00221708116445, 0.00152797367184, 0.00157932519742, 
0.00220077873709, 0.00207100591716, 0.00260208166533, 0.00310438494373, 
0.00311149524633, 0.00385928454802, 0.00292575886871, 0.00222622707516, 
0.00329074719319, 0.00282614641262, 0.00287542899545, 0.00221198156682, 
0.00311754997249, 0.00315623356128, 0.00287696733796, 0.00296425457716, 
0.00263875450787, 0.00208654631226, 0.00179601096512, 0.00164676821737, 
0.00206262891431, 0.00235895419697, 0.00241963359834, 0.0028610523697, 
0.00516910352976, 0.00160170848905, 0.00254951951363, 0.00275583318023, 
0.00298309579052, 0.00286944045911, 0.00288739172281, 0.00394434096636, 
0.00254428026226, 0.00285214831171, 0.0034924330617, 0.00246440306681, 
0.00266448042632, 0.00389457476678, 0.00253187449136, 0.00171276869059, 
0.00184647850171, 0.00134132164893, 0.00153860077835, 0.000990752972259, 
0.00117518677075, 0.00312927831019, 0.00188867903566, 0.0024, 
0.00269541778976, 0.00263945099419, 0.00242809114681, 0.00378173960022, 
0.00274725274725, 0.00165039196809, 0.00211665098777, 0.00290275761974, 
0.00149017416411, 0.00105244693913, 0.00309917355372, 0.00240432779002, 
0.00297314875035, 0.0015613519471, 0.00196335078534, 0.00227707441479, 
0.00279302706347, 0.00295450068938, 0.00316811446091, 0.00211501661799, 
0.00168990283059, 0.00195694716243, 0.00131815458358, 0.00112343771942, 
0.00214911555629, 0.00157701068863, 0.00171037628278, 0.00230591852421, 
0.00183217295713, 0.00102810143934, 0.00130396986381, 0.00151476899773, 
0.00188470066519, 0.00220449296662, 0.00238267895991, 0.00238639753406, 
0.00147368421053, 0.00113942407292, 0.0018192844148, 0.00152207001522, 
0.00151433207139, 0.00117096018735, 0.000862626698296, 0.00095087163233, 
0.00137000737696, 0.00119202427395, 0.00170319064381, 0.000805585392052, 
0.0012680297987, 0.00189328743546, 0.00186115764005, 0.000719553876597, 
0.000903505601735, 0.000865501125151, 0.00210241778045, 0.00146432374867, 
0.00130625816411, 0.0011895749973, 0.00135374362178, 0.00120192307692, 
0.00160832544939, 0.0015243902439, 0.00240894199268, 0.00218735140276, 
0.00230658337338, 0.00188548179022, 0.0016582220175, 0.00263086274154, 
0.00155166119022, 0.00204834084392, 0.00194670884536, 0.00308959835221, 
0.00154400411734, 0.00152526215443, 0.00343364976772, 0.00269282554337, 
0.00235928547354, 0.00230846919636, 0.00300120048019, 0.00327833023713, 
0.00347844418678, 0.00259690295277, 0.00157392833997, 0.00345536047815, 
0.00336884275699, 0.0023862129916, 0.00216094735932, 0.00478603603604, 
0.00330652368186, 0.00551636824019, 0.00313624204409, 0.00253692126484, 
0.00201631381175, 0.00243072435586, 0.00229410415233, 0.00386954118297, 
0.00298111957602, 0.00305261267732, 0.0038211692778, 0.00334759159383, 
0.00479287915098, 0.0045891294995, 0.00525831471014, 0.00800376647834, 
0.0076613299283, 0.00638604065479, 0.00587868531219, 0.00633955709944, 
0.00453494575849, 0.00617283950617, 0.00314804075884, 0.00425604358189, 
0.00536642629549, 0.00422936152908, 0.00234329232572, 0.00454545454545, 
0.00305280528053, 0.00389501993879, 0.0040267034015, 0.00275554389188, 
0.00409706901986, 0.00506904387345, 0.0065987933635, 0.00594701748063, 
0.00343473994112, 0.00579983814405, 0.00750664048966, 0.00365965233303, 
0.00467423447486, 0.00348250043531, 0.00464471968709, 0.00603621730382, 
0.00358154256205, 0.00445752733389, 0.00501562243052, 0.0035344609947, 
0.00410480349345, 0.00467578297309, 0.00265729470255, 0.00210758731433, 
0.00223771408899, 0.00218998083767, 0.00309374033206, 0.00291738496221, 
0.00184956843403, 0.00297202797203, 0.00329329717164, 0.00318889514162, 
0.00397442543632, 0.00481400437637, 0.002580169554, 0.00440303092361, 
0.00335956997504, 0.00318415000884, 0.00269284225156, 0.00242217637032, 
0.00381436745073, 0.00238326418925, 0.0037407568508, 0.00290474156343, 
0.00335156112189, 0.00227624510607, 0.00376647834275, 0.00223313979455, 
0.00197441840501, 0.00214676034348, 0.00225250591283, 0.00140002545501, 
0.0034896070399, 0.00220115137149, 0.002828854314, 0.00418702023726, 
0.00176056338028, 0.00393487109905, 0.00217939894471, 0.00331724969843, 
0.00234508884279, 0.00282099504189, 0.00239295786685, 0.00269893783737, 
0.00263828238719, 0.00250671441361, 0.00231640356898, 0.00231481481481, 
0.00127947358801, 0.0017254601227, 0.00207530388378, 0.00185655657612, 
0.00131525698098, 0.00227864583333, 0.0018737557091, 0.00220458553792, 
0.00184409052808, 0.00109629088251, 0.00253263198909, 0.00228267072475, 
0.00170293282876, 0.00134198165958, 0.000833333333333, 0.00269179004038, 
0.00198744769874, 0.00209205020921, 0.00146132066855, 0.00113981762918, 
0.00185131053298, 0.00194612311789, 0.00203956761167, 0.00111460127673, 
0.00170631335943, 0.00186142709411, 0.00183094293561, 0.00194452973084, 
0.0014944704593, 0.00153720024595, 0.00184561936815, 0.00151190626181, 
0.000897397547113, 0.00222869878279, 0.00201428309833, 0.00202391904324, 
0.00244157656087, 0.00256, 0.00184501845018, 0.00160256410256, 
0.00115813855549, 0.0016858389528, 0.001741042793, 0.0026610387227, 
0.00167193015047, 0.00201060135259, 0.00219058050383, 0.00233330341919, 
0.000963457435827), .Tsp = c(1, 15.9583333333333, 24), class = "ts")

Saya tahu bahwa T1 dan T2 berkorelasi dan menganggapnya sebagai kebenaran dasar sehingga metrik jarak apa pun harus memberi tahu saya bahwa (T1, T2) lebih dekat daripada (T2, T3) dan (T1, T3). Namun, ketika menggunakan dtwdalam R, saya mendapatkan yang berikut:

> dtw(T1, T2, k = TRUE)$distance; dtw(T1, T3, k = TRUE)$distance; dtw(T3, T2, k = TRUE)$distance
[1] 1.107791
[1] 1.568011
[1] 0.4102962

Adakah yang bisa menjelaskan cara menggunakan Dynamic Time Warping untuk pertanyaan tetangga terdekat?

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1
Bisakah Anda menjelaskan apa yang Anda maksud dengan "permintaan tetangga terdekat" dalam konteks ini dan bagaimana hal itu terkait dengan dtw?
whuber
@whuber: Kesan saya pada DTW adalah metrik jarak untuk deret waktu. Dan ada makalah ini yang menunjukkan bahwa: Faster Retrieval with a Two-Pass Dynamic-Time-Warping Lower Boundoleh Daniel Lemire et. al dengan kode yang disediakan di code.google.com/p/lbimproved Namun, saya mencoba memahami metrik ini sebelum menggunakannya.
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Jawaban:

22

Pembengkokan waktu dinamis membuat asumsi tertentu pada kumpulan data Anda: satu vektor adalah dereteched deret waktu non-linear . Tetapi juga mengasumsikan bahwa nilai aktual berada pada skala yang sama.

x=1..10000Sebuah(x)=1dosa(0,01x)b(x)=1dosa(0,01234x)c(x)=1000dosa(0,01x)

SebuahbSebuahcSebuahcSebuahb

DTW bukan senjata ajaib Anda untuk menyelesaikan semua kebutuhan pencocokan seri waktu Anda. Itu membuat asumsi khusus pada jenis kesamaan yang Anda minati . Jika itu tidak cocok dengan data Anda, itu tidak akan berfungsi dengan baik. Menilai dari seri data yang Anda bagikan, Anda tidak perlu penyelarasan temporal (yang dilakukan DTW), tetapi sebenarnya beberapa normalisasi yang sesuai dan mungkin transformasi fourier sebagai gantinya. Jarak lintas treshhold mungkin juga cocok untuk Anda, lihat misalnya:

  • Pencarian Kesamaan pada Time Series Berdasarkan pada Threshold Queries,
    Johannes Aßfalg, Hans-Peter Kriegel, Peer Kröger, Peter Kunath, Alexey Pryakhin dan Matthias Renz, EDBT 2006
Memiliki QUIT - Anony-Mousse
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+1 Terima kasih atas saran Anda. Bisakah Anda mengarahkan saya ke beberapa pekerjaan pada transformasi Fourier? Dan akhirnya, saya bertanya-tanya - apakah ada implementasi praktis yang bisa saya coba? Maksud saya, beberapa database yang benar-benar mengimplementasikan ini dalam tindakan.
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1
Saat mencari lebih banyak tentang ini, saya menemukan karya representasi simbolis SAX dari Keogh et. al dari Univ. dari Riverside. Apakah Anda punya komentar tentang itu?
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Seorang teman bereksperimen dengan SAX untuk seri waktu gerak (yaitu klasifikasi gerakan). Itu tidak berhasil untuknya. Itu sebabnya saya tidak menyarankannya. Keogh menghasilkan karya-karya seperti orang gila, tetapi mereka tidak terlalu meyakinkan IMHO. Dia pasti telah mengusulkan setidaknya 10 fungsi jarak untuk deret waktu, yang tentu saja semua mengungguli satu sama lain.
Memiliki QUIT - Anony-Mousse
2
@Anony, saya mengambil umbrage dengan “Keogh menghasilkan kertas seperti orang gila, tapi mereka tidak terlalu meyakinkan IMHO. Dia pasti telah mengusulkan setidaknya 10 fungsi jarak untuk deret waktu, yang tentu saja semuanya mengungguli satu sama lain. "Saya belum mengusulkan" fungsi jarak setidaknya 10 untuk deret waktu ". Saya sangat menganjurkan untuk 2 fungsi jarak untuk deret waktu 1) Jarak Euclidean (ED): dua ribu tahun 2) DTW: 50 tahun Kedua ukuran itu digunakan di 90% dari kertas saya, dan saya tidak mengusulkan atau menciptakan keduanya. Saya telah mengusulkan perubahan kecil untuk ED dan DTW. Anda mengatakan "mereka tidak IMHO sangat meyakinkan.". ...
2
Saya menguji dengan eksperimen yang dapat direproduksi pada setiap dataset publik di dunia, dan memberikan semua kode saya. Mungkin beberapa orang di sini mengalami kesulitan menggunakan salah satu ide saya, tetapi lebih dari 2.000 orang telah berhasil menggunakan salah satu ide saya (tekan Google) jadi mungkin masalahnya bukan pada ide.
4

Pada 1980-an, waktu dinamis warping adalah metode yang digunakan untuk pencocokan templat dalam pengenalan ucapan. Tujuannya adalah untuk mencoba mencocokkan serangkaian waktu dari pidato yang dianalisis dengan templat yang tersimpan, biasanya dari seluruh kata. Kesulitannya adalah orang berbicara dengan kecepatan berbeda. DTW digunakan untuk mendaftarkan pola yang tidak diketahui ke templat. Itu disebut "lembaran karet" yang cocok. Pada dasarnya Anda mencari melalui beberapa kemungkinan terkendala tentang bagaimana deret waktu dapat dikembangkan secara lokal untuk mengoptimalkan kecocokan global. Pendekatan ini terbukti hampir sama dengan model Markov tersembunyi.

Mike Allerhand
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4

Pertama, Anda mengatakan "metric time warping metric", namun DTW adalah ukuran jarak, tetapi bukan metrik (tidak mematuhi ketimpangan segitiga).

Paper [a] membandingkan DTW dengan 12 alternatif pada 43 dataset, DTW benar-benar bekerja dengan sangat baik untuk sebagian besar masalah.

Jika Anda ingin mempelajari lebih lanjut tentang DTW, Anda dapat melihat tutorial Keoghs http://www.cs.ucr.edu/~eamonn/Keogh_Time_Series_CDrom.zip (peringatan 500 mcg)

Pass-nya pas.

Ada juga tutorial tentang SAX http://www.cs.ucr.edu/~eamonn/SIGKDD_2007.ppt

[a] Xiaoyue Wang, Hui Ding, Goce Trajcevski, Peter Scheuermann, Eamonn J. Keogh: Perbandingan Eksperimental Metode Representasi dan Ukuran Jarak untuk Data Seri Waktu CoRR abs / 1012.2789: (2010)

Eamonn Keogh
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+1 Terima kasih banyak atas jawaban Anda. Saya membuat koreksi untuk pertanyaan saya. Sekarang, saya mengerti Anda adalah pelopor dalam rangkaian waktu. Akan lebih baik jika Anda memiliki beberapa saran tentang kasus spesifik saya yang saya masukkan di salah satu komentar: Data deret waktu yang saya miliki adalah dari jaringan seperti twitter internal dan seri itu sendiri mewakili jumlah pesan yang dihasilkan pada suatu tema. Saya ingin mencari topik lain yang memiliki timeline yang sama dengan yang diberikan. Sekali lagi terima kasih atas waktunya.
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