I am running a two regression analysis. One between DA and both PROT and AUFEE (DA is the dependent variable). The results seems fine. However, when I run between AUFEE and PROT (AUFEE is the dependent variable) without DA, I am getting really high coefficients and so I though this might be a multicollinearity problem. BUT I check pearson correlation matrix and nothing is above 5, also VIF for the first regression, the maximum is 3 and AUFEE has 1.91. What could be the issue here. All regression results are displayed below. Thanks for your help and please let me know if you need more information.


Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input double DA byte PROT double(AUFEE SIZE) byte(BIG4 LOSS) double(CFO LEV ROA)
   -1.77506422996521 1  .0005100634298287332 25.057283401489258 1 1     .1057608351111412  .5921573638916016   .006255737505853176
  -.9878171682357788 1  .0032628243789076805 19.459911346435547 1 1     .1057066023349762 .47960057854652405 -.0017049635061994195
   -.629041850566864 1  .0013864407083019614  22.23971176147461 1 0   .009604520164430141  .7221246957778931    .07396839559078217
  -2.578303098678589 1 .00037108216201886535  23.63926124572754 1 0    .08683876693248749  .4484545588493347    .16247184574604034
 -1.2266926765441895 1 .00034350951318629086 24.779787063598633 1 0    .10834021121263504  .6821179389953613    .11709622293710709
  -.4336802661418915 0 .00028271027258597314 23.788198471069336 1 0    .08389580994844437  .4919983148574829  -.013157281093299389
 -.07259324193000794 1  .0031915747094899416  22.06157684326172 1 1   .002454848261550069  .6391701102256775  .0009966951329261065
  -1.194482684135437 0   .004108223132789135  17.86733055114746 0 1    .13857948780059814 .46005356311798096    .01779068633913994
 -2.8071320056915283 1   .005903108045458794  18.89883804321289 1 1    .14684134721755981 .28952327370643616    .04217345640063286
 -.17034991085529327 0  .0018484219908714294  20.20169448852539 0 0   .021184036508202553  .4453551173210144    .04076066240668297
 -1.4309687614440918 0  .0029281876049935818 20.163108825683594 1 1   -.01188828144222498  .8372160792350769   -.12140201777219772
 -1.4755034446716309 0  .0016267688479274511 21.595396041870117 1 1  -.016426080837845802  .6334603428840637   .017342787235975266
  -.5812863707542419 0  .0008289089892059565  22.78428077697754 1 1   .038773342967033386  .5982671976089478   -.08160842210054398
 -.37801194190979004 0 .00020431529264897108  23.79512596130371 1 1    .17229267954826355  .5916967988014221  .0018533963011577725
 -2.4270706176757812 1  .0018645942909643054 20.844589233398438 1 0    .10041678696870804  .5422655940055847    .05484011769294739
  -2.214040756225586 1     .0001635854132473 26.547836303710938 1 1    .18973545730113983  .7326921224594116    .16323009133338928
  -4.322081565856934 1  .0017127073369920254      21.1162109375 1 0    .06993813067674637  .6228328943252564   -.01461381558328867
 -4.8460493087768555 1 .00041318219155073166 24.432756423950195 1 0   -.11971073597669601  .5335880517959595   .044326893985271454
  -2.930457592010498 1  .0011416099732741714 21.034889221191406 1 0    .11596635729074478  .5229624509811401   .043734773993492126
 -2.5332694053649902 0  .0008195746340788901 22.704404830932617 1 0   .029205041006207466  .5075162053108215    .06964556872844696
 -3.1961634159088135 1   .001886824145913124  18.57480812072754 0 1   .027096308767795563  .3882003128528595    .01507748756557703
 -1.5971938371658325 1  .0010833105770871043   20.0311222076416 1 1   .021941352635622025  .0936979278922081    .01483910158276558
 -2.6043076515197754 0  .0011206968920305371 22.544471740722656 1 0     .2992260754108429 1.0225106477737427   .034712668508291245
 -4.0094709396362305 1   .001546847284771502  22.36758804321289 1 0    .08913936465978622  .8155287504196167    .09027522802352905
  -3.485934019088745 1  .0005943619762547314  22.87089729309082 1 0    .05572352185845375  .5165572166442871   .020589157938957214
   .2987738847732544 0  .0005632395623251796 20.808130264282227 0 0    .11152207106351852 .44539350271224976    .04704153165221214
  -3.190335988998413 1  .0006560316542163491  23.56637191772461 1 0    .09138687700033188   .764342725276947    .02178344689309597
 -2.3192639350891113 1  .0012950878590345383 21.756084442138672 1 0    .10026520490646362  .5717092156410217    .05916261300444603
  -4.975456237792969 0  .0008192966924980283 21.569862365722656 1 0    .07901201397180557  .6152870655059815    .06175459176301956
 -4.1124444007873535 1  .0023575876839458942 22.448007583618164 1 0    .06681329011917114  .2834998667240143    .06515943259000778
-.030439576134085655 0 .00017899753584060818    23.364013671875 1 1 -.0036373829934746027  .4232049882411957   -.04561563581228256
  -1.523878574371338 1   .003978000022470951  17.16151237487793 0 1     .1197550967335701 .15742012858390808    .10740075260400772
  -4.998481273651123 1   .001160908374004066 20.869361877441406 1 0     .1534736007452011  .2648681104183197     .1134166568517685
 -2.3436777591705322 0  .0009778623934835196 21.162443161010742 1 1  -.024470798671245575  .7120593786239624  -.034860074520111084
   .4077340364456177 0   .000308783637592569 24.278213500976562 1 0    .17704389989376068  .5962098836898804     .1406276822090149
  -3.667536497116089 0  .0060606058686971664 17.899282455444336 0 1   -.06022614240646362  .4874766170978546  -.006249052472412586
  -3.391090154647827 1   .000735024455934763 22.349924087524414 1 1    .13764716684818268  .5338039994239807   .052213918417692184
  -.9894350171089172 1   .002123710000887513  20.21846580505371 1 0    .10093172639608383  .6593039631843567    .03047913685441017
   -3.30741024017334 1  .0004700254648923874 23.299535751342773 1 1    .09622135013341904  .9154244065284729   .016048068180680275
  -1.936282992362976 0 .00033491026260890067 24.435935974121094 1 0    .06813346594572067  .8454703092575073   .033273931592702866
 -3.7366139888763428 0  .0005853009643033147 21.882596969604492 1 1    .07728633284568787  .5231507420539856    .05238722637295723
 -2.7275774478912354 1    .00509294681251049 19.621503829956055 1 0    -.2151138037443161  .8977233171463013    .06880539655685425
 -3.2721617221832275 1  .0020385372918099165 20.344894409179688 1 0    .10724112391471863  .5379195809364319    .05240621417760849
   -3.03253436088562 1  .0018844660371541977 20.401979446411133 0 0    .04866178706288338  .2697513699531555    .09462284296751022
 -3.1526224613189697 1   .002235580235719681 20.686298370361328 1 0    .16011740267276764  .3682038486003876    .09446948766708374
 -1.8770138025283813 0  .0023966713342815638 20.698490142822266 1 0     .3120976984500885  .3938324749469757    .21070003509521484
 -1.1195992231369019 1   .002813705476000905  17.67653465270996 0 0    -.5394664406776428  .4379551410675049   -.42938923835754395
 -1.3462677001953125 1   .005897567141801119 17.319475173950195 0 1    .05908976495265961  .1048816442489624   .060185883194208145
  -3.068446397781372 0  .0007065773825161159 20.953027725219727 1 0    .15786661207675934  1.535201549530029     .1231025978922844
 .010193313471972942 0  .0005363852251321077 22.526493072509766 1 1    .12695351243019104  .5956963300704956    .09368615597486496
  -2.914595365524292 0  .0007282359874807298  21.26860809326172 1 0    .08383487164974213  .7256550192832947     .2044980227947235
 -1.4748319387435913 0  .0011545454617589712  22.35563850402832 1 1    .19604742527008057  .8907349705696106     .1602814644575119
  -4.815817356109619 1  .0007022219360806048  21.82518196105957 1 1    .05495645850896835  .8487784266471863 -.0066214208491146564
  -2.290703773498535 0  .0003095704014413059 25.144704818725586 1 0    .08677300810813904  .7709815502166748    .07731686532497406
 -1.9025307893753052 0   .005741371773183346 20.849018096923828 1 1    .08190374076366425   .518568754196167  -.028378257527947426
  -2.002718687057495 1   .003385481657460332  19.54550552368164 0 1    .15652401745319366 .11930135637521744    .10621558129787445
  -2.218651533126831 0  .0025759460404515266 17.878467559814453 0 1   .049879059195518494  .1543528288602829   -.20338457822799683
 -1.7408822774887085 0   .005897214636206627 18.636768341064453 1 1  -.002373957075178623  .4825372099876404  -.022695595398545265
  -.7971984148025513 0   .001675428356975317 20.604156494140625 1 1    .08049510419368744  .3972340226173401   .028208505362272263
 -3.5342774391174316 0   .000766665325500071  20.75233268737793 1 1   .019441811367869377  .4458874464035034   .018836457282304764
  -2.718313217163086 1  .0005439431988634169  21.14680290222168 1 0    .21723560988903046  .6190924644470215     .1621234118938446
 -1.6080288887023926 0  .0015118964947760105  22.12017822265625 1 0    .11515235900878906    .62225741147995    .08301382511854172
 -1.4211368560791016 1  .0009439182467758656 23.448631286621094 1 0    .05354965850710869  .9157384634017944   .028764251619577408
 -3.1363840103149414 1  .0006473028915934265 23.670963287353516 1 0    .13156293332576752  .5667296051979065    .11231770366430283
  -.2930336892604828 0   .008676238358020783 17.226228713989258 0 0     .4006849229335785 .27163469791412354    .17991217970848083
 -1.6988451480865479 0   .003794526681303978  18.83070182800293 0 0     .0778937041759491 .22343961894512177   -.16197365522384644
  -4.877298355102539 1     .0001635854132473 24.443885803222656 1 0     .1531577706336975  .7263986468315125    .07113102078437805
  -2.597773313522339 0 .00028591600130312145  25.01387596130371 1 0    .04866776987910271  .8434345722198486     .0445549301803112
 -3.5788116455078125 0  .0012292723404243588 21.558387756347656 1 1     .1536177396774292   .602874219417572    .06491269916296005
  -4.097415447235107 1  .0013887437526136637  21.53094482421875 1 0     .0873609408736229  .3752728998661041    .04243464022874832
 -3.7514069080352783 1  .0018248828127980232  22.18464469909668 1 1  -.019827816635370255 1.0067719221115112   -.13189081847667694
  .16378659009933472 0  .0035664751194417477 17.768386840820312 0 1   .014518075622618198  .6193721890449524  -.046961698681116104
 -3.6386020183563232 0 .00042286328971385956 21.955900192260742 1 1    .10639310628175735  .5267820954322815    .03238270431756973
  -4.448879241943359 1  .0014442310202866793  22.01546859741211 1 0    .05211934819817543  1.067402720451355 -.0030213140416890383
  -4.698802947998047 1  .0011119721457362175   21.9959716796875 1 0    .07074777036905289   .776361882686615  -.011118890717625618
 -3.0903754234313965 0  .0015673160087317228 21.519704818725586 1 1   .027651449665427208  .6083189845085144   .025800054892897606
 -1.5777647495269775 0  .0051612211391329765 17.495147705078125 0 0   .007751937955617905  .4762817919254303  -.023264029994606972
  -.9979426860809326 0   .011638970114290714   17.2439022064209 0 1    -.0161106176674366 .39053428173065186  -.012002465315163136
  -3.577202796936035 1  .0006307187722995877 22.510936737060547 1 1   .051061294972896576   .567409336566925    .03981693834066391
   -.984097957611084 0   .002295163692906499 19.015377044677734 0 0    .07296920567750931  .4655444622039795    .08003398776054382
   -3.47652530670166 1  .0026362037751823664 21.136037826538086 1 1   -.03632103279232979  .8874917030334473  -.010589013807475567
  -.6766753792762756 1  .0006130643887445331  24.16021728515625 1 1    .08147625625133514  .4808310866355896    .06898880749940872
 -3.9562315940856934 0   .005665299948304892  16.40139389038086 0 1   .009690645150840282 .04143126308917999 -.0007532956660725176
  -1.467341661453247 1  .0010004903888329864  23.74354362487793 1 0    .14742520451545715  .5963799357414246     .1125042662024498
  -2.239891529083252 0   .000913308234885335  20.49306297302246 0 1     .2767569422721863  .7413440942764282   .016032790765166283
  -3.752398729324341 1  .0016495921881869435 19.710147857666016 0 0    .15582551062107086 .20369334518909454    .10310808569192886
  -.7153881192207336 0   .009840201586484909 16.556995391845703 0 0   -.10281749069690704 .03333333507180214     .2990741431713104
   .1994035840034485 1  .0013395828427746892 22.701974868774414 1 0    .12244898080825806   .552216112613678    .08119279891252518
  -.9942150712013245 0  .0026922868564724922  17.39032554626465 0 1   -.09815884381532669 .10541358590126038    .06565231829881668
  -.9779375791549683 0  .0072632841765880585 17.117292404174805 0 0     .1489812284708023  .7053127884864807    .13795515894889832
 -1.7613250017166138 1     .0058419369161129 19.297889709472656 1 0    .15968061983585358 .44144782423973083    .12675008177757263
 -2.7633066177368164 1  .0010956537444144487 19.613189697265625 0 0      .190653994679451 .26664623618125916    .11005237698554993
 -2.5592386722564697 1     .0001635854132473 26.577451705932617 1 0    .09102248400449753  .4421995282173157    .05652569234371185
  .08647548407316208 1  .0018410219345241785 23.023277282714844 1 1    .04001607745885849  .6781327724456787    .05033937096595764
 -2.4690372943878174 0  .0024267607368528843 19.866682052612305 1 1    .07454824447631836  .6290855407714844   -.17332375049591064
  -2.771878480911255 1   .001774664968252182  20.74678611755371 1 0    .09352010488510132  .4822230935096741     .0918148085474968
  -2.642206907272339 0  .0027788232546299696 19.353973388671875 1 1   .023616479709744453 .19214509427547455   -.12822125852108002
  -4.515648365020752 1   .001311038271524012 21.769018173217773 1 0    .11124951392412186   .557810366153717    .05523034930229187
 -1.7170979976654053 0  .0035499657969921827  18.71006202697754 0 1    .16438032686710358 .11566337198019028    .11468254029750824
 -2.9773106575012207 1   .003366215154528618 19.798328399658203 1 0     .1001773402094841   .630622148513794   .010371801443397999
end
DA>PROT+AUFEE
Source SS df MS Number of obs = 1,656
F(17, 1638) = 17.72
Model 450.951628 17 26.5265663 Prob > F = 0.0000
Residual 2452.73956 1,638 1.497399 R-squared = 0.1553
Adj R-squared = 0.1465
Total 2903.69119 1,655 1.75449618 Root MSE = 1.2237
DA Coef. Std. Err. t P>t [95% Conf. Interval]
AUFEE 10.43736 4.050757 2.58 0.010 2.49215 18.38257
PROT -.2301441 .0644663 -3.57 0.000 -.3565891 -.1036991
BIG4 .003886 .0856561 0.05 0.964 -.1641211 .171893
SIZE -.0501679 .0228979 -2.19 0.029 -.0950801 -.0052556
LEV -.0056546 .1087051 -0.05 0.959 -.2188703 .207561
LOSS .1556403 .0628062 2.48 0.013 .0324514 .2788292
CFO -.2563862 .1489073 -1.72 0.085 -.548455 .0356827
ROA -.0780845 .1520259 -0.51 0.608 -.3762701 .2201012
Variable VIF 1/VIF
AUFEE 1.91 0.524244
PROT 1.15 0.870306
BIG4 1.89 0.529326
SIZE 3.12 0.320868
LEV 1.15 0.866217
LOSS 1.09 0.920694
CFO 2.98 0.335817
ROA 2.81 0.355428
AUFEE>PROT
Source SS df MS Number of obs = 1,656
F(16, 1639) = 92.96
Model .082816424 16 .005176027 Prob > F = 0.0000
Residual .091256798 1,639 .000055678 R-squared = 0.4758
Adj R-squared = 0.4706
Total .174073222 1,655 .00010518 Root MSE = .00746
AUFEE Coef. Std. Err. t P>t [95% Conf. Interval]
PROT .0001482 .0003931 0.38 0.706 -.0006228 .0009192
BIG4 .0020111 .0005199 3.87 0.000 .0009912 .0030309
SIZE -.002384 .0001266 -18.83 0.000 -.0026323 -.0021357
LEV .004129 .000655 6.30 0.000 .0028443 .0054137
LOSS -.0006796 .0003826 -1.78 0.076 -.0014301 .0000708
CFO -.0163637 .0008131 -20.13 0.000 -.0179585 -.014769
ROA .0093227 .000898 10.38 0.000 .0075615 .011084
Variable VIF 1/VIF
PROT 1.15 0.870382
BIG4 1.87 0.534158
SIZE 2.56 0.390286
LEV 1.13 0.887221
LOSS 1.08 0.922467
CFO 2.39 0.418806
ROA 2.64 0.378802

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