Zero Observations String Variable

[Sky Emanuel]

Hi,

I try to import data from an xls file, containing both numeric as well as alphabetic values. Please see how my data looks like. When I use the command 'summarize', however, the variable Country says zero observations. This, even if it states that Country has a "str3" storage type.
How should I proceed?

Date	Country	NPL_Ratio	GDP_Growth	Unemployment_rate	Inflation_Rate	Interest_Rate	Private_Debt_Change	Stock_Return
1999	AUT	-1,769551079	-0,003596191	0,047	0,005689938	0,038426		-0,095191797
2000	AUT	-1,619788758	-0,09241522	0,0469	0,023448629	0,057533	0,051618	-0,008361147
2001	AUT	-1,619788758	0,000673837	0,0401	0,026500008	0,050996	0,016779	0,001044988
2002	AUT	-1,522878745	0,084719761	0,0485	0,018103579	0,050646	0,003698	0,013364127
2003	AUT	-1,522878745	0,223881294	0,0478	0,013555537	0,042233	0,029472	0,112757295

[Rich Goldstein]

Stata does not allow the use of the -summarize- command on string variables; you did not supply a data example using -dataex- (please read the FAQ), but it appears that the -destring- command is what you want; see

h destring

[Sky Emanuel]

Stata does not allow the use of the -summarize- command on string variables; you did not supply a data example using -dataex- (please read the FAQ), but it appears that the -destring- command is what you want; see

h destring

I do not want to destring the variable. I want to keep it as string since it contains categorical data. However, I wonder what the issue is since it does not show any number of observations.

Please see dataex below:

* Example generated by -dataex-. For more info, type help dataex
clear
input int Date str3 Country double(NPL_Ratio GDP_Growth Unemployment_rate Inflation_Rate Interest_Rate Private_Debt_Change Stock_Return)
14245 "AUT"   -1.76955107862173    -.00359619144939654                .047   .00568993765885587               .038426                      .  -.09519179672544546
14610 "AUT" -1.6197887582883939      -.092415220140246 .046900000000000004  .023448628535727697               .057533     .05161809928247165 -.008361146817868263
14976 "AUT" -1.6197887582883939   .0006738373772020043               .0401    .0265000077279529               .050996    .016779224396017554  .001044987891582142
15341 "AUT" -1.5228787452803376     .08471976102475824 .048499999999999995    .0181035787764132   .050646000000000004   .0036976170912080895  .013364126523785477
15706 "AUT" -1.5228787452803376     .22388129367120513               .0478    .0135555370896445               .042233    .029471960704052325   .11275729455391012
16071 "AUT" -1.5686362358410126     .14916783622162558               .0583  .020612061803286598               .042664   -.014512922465208767   .43314089161075725
16437 "AUT"  -1.585026652029182    .049601587675601765 .056299999999999996    .0229913785639285               .035641     .03160513751597063   .45650117592707196
16802 "AUT" -1.5686362358410126     .06333572582659588               .0524    .0144154851119019               .033271   -.006388110292679767   .30447304254722934
17167 "AUT" -1.6575773191777938     .15739909247155795 .048600000000000004    .0216855528800755                 .0406    .030505805943712005    .1919113351728225
17532 "AUT" -1.7212463990471711      .1098936107350134 .041299999999999996    .0321595033239883               .042169    .012286732874967945   -.2805998574329867
17898 "AUT" -1.6382721639824072     -.0710223261304846                .053   .00506308827696486               .039981    .006917803911703883   -.3680588511991074
18263 "AUT"  -1.548103086646509   -.021748068264216106               .0482    .0181353438995065               .037512     .02598213728061948    .2054538423087556
18628 "AUT" -1.5675406232859719     .09937467364586915 .045599999999999995    .0328657914875376               .035407   -.011322822182991521  .008655582050343101
18993 "AUT" -1.5507746915781435    -.05085158094479031               .0487    .0248567562177017               .032696    .002093467151037541  -.13389542816988592
19359 "AUT"  -1.542641993656244     .05012925321180196 .053399999999999996    .0200015616900603                .01923    .030107526881720525   .12710629255427333
19724 "AUT" -1.4592489510977256     .02906110456372313               .0562    .0160581182954471               .021311   -.027139874739039723  -.01157841843103307
20089 "AUT" -1.4694366203889289    -.13708863132738044               .0572   .00896563335260302               .005434   -.006866952789699631  .008683961965352038
20454 "AUT" -1.5694057793134415     .03591005471060967               .0601   .00891591752655335               .007672     .00802568218298563 -.030426199999999994
20820 "AUT" -1.6254532720610406     .05404217037965471                .055    .0208126911385587               .005705  -.0008574228319451664   .33848191855019183
21185 "AUT" -1.7252811644919177     .09130357648029076 .048499999999999995    .0199837981429546               .006692    .009317150913326041   .07442764708647295
21550 "AUT"  -1.788180236228491   -.023128396873448476               .0449    .0153089564152645                .00452   -.008198712498481761  -.06729750004661685
21915 "AUT"  -1.802228631052083    -.02202307329030517               .0536    .0138191063351859 -.0008680000000000001     .06741779437878873    -.183444956209487
22281 "AUT"                   .      .1053424301584126 .061799999999999994  .027666666666666503              -.003995  -.0029256539697108093    .3740453774137473
14245 "BEL" -1.5686362358410126 -.00010961905015736383  .08650000000000001    .0112084823417844                  .039                      .    .0334180823319908
14610 "BEL" -1.5528419686577808     -.0835705996131528               .0659    .0254451776190906                 .0579    .057005377865836405  -.09757991143664953
14976 "BEL"  -1.537602002101044  -.0006289653309244102 .061799999999999994  .024692582308607797                 .0516    .032401456726649645  -.06020891084733814
15341 "BEL" -1.5228787452803376      .0906111139270448               .0691    .0164521436175359                 .0508   -.007625667894381987  -.10927095942222793
15706 "BEL"  -1.585026652029182     .23161890007745933               .0768    .0158896399970379   .042800000000000005    .024359644537375835  -.15111808677974006
16071 "BEL" -1.6382721639824072     .16051055961560232               .0736    .0209728311239314                 .0426    .018677281077770957   .31044085683074624
16437 "BEL" -1.6989700043360187     .04573943156291746  .08439999999999999  .027814326367002498                 .0359   -.005610660254483457    .2932505371910241
16802 "BEL" -1.7695510786217261    .057922871423870315               .0825    .0179120770070454                 .0337    .022619647355163697   .24091113871409636
17167 "BEL"  -1.853871964321762     .15356335465035112               .0746     .018230563002681                 .0406     .05507660475885496    .1360808969822687
17532 "BEL" -1.7695510786217261     .09828909205950172               .0698    .0448944420508401                 .0425     .10575710883877303  -.26999334745276976
17898 "BEL" -1.5086383061657274    -.06677363852533492               .0791 -.000531456741253762   .041299999999999996    .036230048137826334  -.30488838833201937
18263 "BEL" -1.5530576183787825  -.0018975410685062044  .08289999999999999    .0218929920422458                 .0375    -.05203748981255108   .19636642335793472
18628 "BEL" -1.4811834754625894     .08597716131121151  .07139999999999999  .035320821072274404                 .0414     .05072432618320953   -.0359163815140629
18993 "BEL" -1.4273316580160689    -.05116591079793375               .0754    .0283966343445897   .041100000000000005    .016814629955406328  .030215528887748762
19359 "BEL" -1.3721243515708175     .05102453939536767               .0843    .0111309594027537                 .0231 -.00024140983342718837   .15931543968044995
19724 "BEL"  -1.379271750495911    .026312813937933957               .0852   .00340002833356965                 .0245 -.00032195750160975205   .18072386651799777
20089 "BEL" -1.4214352796422318    -.13658644069695572               .0848   .00561429152790106                 .0073   .0010064412238325066    .1384563260830363
20454 "BEL"  -1.464448924559488    .029300385178520835               .0783    .0197385264653172                 .0086       .097124472149608  -.04767629999999997
20820 "BEL"   -1.53390531081779     .05600811882394717               .0709    .0212597086002609   .006999999999999999   -.049376832844574954     .065956879997841
21185 "BEL" -1.6443052511323342     .08149633794745985 .059500000000000004    .0205316499865181   .006999999999999999    .003933212509158467 -.048880741102669927
21550 "BEL" -1.6804629845215553   -.014085284410151118               .0536    .0143681956996435                 .0077   -.004109852122143583 -.040049283522562186
21915 "BEL" -1.6840384474823311   -.020711340013808803               .0555  .007407918122203851                -.0003     .03675563097809333  -.15977746925275282
22281 "BEL" -1.6922343933812187     .13283192737680333               .0626  .024402485114408103                -.0036    -.03958186079386921   .17724545715683926
14245 "HRV"  -.9871627752948278     -.0833636953541459               .1356  .040191387559808396                     .                      .  -.13307361486184668
14610 "HRV" -1.0222763947111522   -.061347352355110865               .1606  .046113155473780004                     .                      .   .25540831368563743
14976 "HRV"  -1.136677139879544     .04164408310749774               .1582     .037767024666589                     .                      .    .1404953606418744
15341 "HRV"  -.9913998282380825      .1595698551730119               .1505    .0167178437393382                     .                      .   .20166073821593483
15706 "HRV" -1.0506099933550872     .31803903971281133               .1392    .0176733780760626                     .                      .   -.0325049292236281
16071 "HRV"    -1.1249387366083     .18696626663262123               .1366    .0205539679050332                     .                      .   .13782055407730492
16437 "HRV"  -1.207608310501746      .0768697564356909                .126    .0331717824448043                     .                      .    .4951505108609809
16802 "HRV" -1.2839966563652008     .09943843917164229  .11130000000000001     .031898259147295                 .0403                      .    .4428625989266471
17167 "HRV" -1.3187587626244128     .19475904952254053  .09910000000000001  .028992827558339197                 .0475                      .    .6865153759761572
17532 "HRV" -1.3098039199714864      .1547144305508618  .08529999999999999    .0607696838798351                 .0555                      .  -.29408300385454106
17898 "HRV" -1.1135092748275182     -.0945914305783189                .092    .0237852845904674                 .0683                      .   -.4328585803976556
18263 "HRV"  -.9549783930986224   -.050604473752262735               .1162    .0103055505333573   .059500000000000004                      .   .06337455180231404
18628 "HRV"  -.9110528044135227     .06549088370984492               .1368  .022727272727272697                 .0655                      .  .045112716579558086
18993 "HRV"  -.8613941911236018    -.08501629705374832               .1593    .0341207349081366                 .0754                      .  -.16399427278800577
19359 "HRV"  -.8116228156386591     .03665287163636999               .1725  .022165820642977997                 .0429                      .   .06809286440042073
19724 "HRV"   -.777124923306181  -.0022740289054340866               .1729  -.00215196159576215   .051100000000000007                      .  -.03359865534568105
20089 "HRV"  -.7870058368709365    -.14326957167699347               .1618  -.00464499004645002                 .0332                      .  -.03588996033651297
20454 "HRV"   -.866161021191456    .032141097645088185                .131   -.0112500000000001                 .0384                      .   .03331199999999995
20820 "HRV"  -.9507238167848703     .06766457919657859               .1121    .0112937210282344   .027999999999999997                      .   .07999423213898611
21185 "HRV" -1.0129185496178397     .09722818311874105               .0843  .015001250104175301                 .0235                      .  -.06368445058160113
21550 "HRV" -1.1555458132688121  -.0003259611780236974               .0662   .00771820346498083                 .0223                      .   .04577084336219414
21915 "HRV" -1.1976073585890323    -.06126807636499992               .0751 .0015481137456202802  .0060999999999999995                      .  -.11440799028485618
22281 "HRV"  -1.244183746305383     .19646051511835913               .0761  .025545069964204598                 .0058                      .   .17807364456077407
14245 "CYP"                   .     .02472356386657607                .057    .0162999999999998                     .                      .                    .
14610 "CYP"                   .    -.04894305846505428 .049699999999999994    .0414165764702056                     .                      .                    .
14976 "CYP"                   .     .04094913896676011               .0398    .0197304191729919                     .                      .                    .
15341 "CYP"                   .     .09858613061460036                .033    .0280115505180746                     .                      .                    .
15706 "CYP"                   .     .27403256872701803               .0414  .041390653868685595                     .                      .                    .
16071 "CYP"                   .     .19076415612974162               .0433  .022862170680167503                     .                      .                    .
16437 "CYP"                   .     .07992843951985226                .053  .025601613233023502                     .                      .                    .
16802 "CYP"                   .     .09132688505317159               .0454  .023046873297855697                     .                      .                    .
17167 "CYP"                   .      .1792184898638723               .0392  .023726518366972198                     .                      .                    .
17532 "CYP" -1.4436974992327127      .1608255128311602               .0365   .04669008419024841                     .                      .                    .
17898 "CYP" -1.3467874862246563     -.0692183866928993               .0536   .00326276652249795                     .                      .                    .
18263 "CYP"  -1.234948686114516   -.007647963105303613               .0626  .024300408410225297                     .                      .                    .
18628 "CYP" -1.0005984356191289     .07033035126447465               .0786  .032894493956421196                     .                      .                    .
18993 "CYP"  -.7357750157575833    -.09313601331548287  .11800000000000001    .0238905410042319                     .                      .                    .
19359 "CYP" -.41389676455476304    -.04400909707537007  .15869999999999998  -.00399357676464408                     .                      .                    .
19724 "CYP" -.34705683230935336   -.030383973288814693               .1609 -.013549888544631199                     .                      .                    .
20089 "CYP" -.32104663392046906    -.14294938016528927               .1491   -.0209699769053118                     .                      .                    .
20454 "CYP" -.43534458615190014      .0567023253477977               .1295   -.0142916666666668                     .                      .                    .
20820 "CYP"  -.5032239035513348     .09020912547528517               .1105     .005317664961745                     .                      .                    .
21185 "CYP"  -.7095090624654381      .1164443281890313               .0837    .0143549119531762                     .                      .                    .
21550 "CYP"  -.7671791666061767    .013237533679565778               .0707 .0025037099675845596                     .                      .                    .
21915 "CYP"  -.8233565669165341    -.03699707106520734               .0759  -.00638422797978907                     .                      .                    .
22281 "CYP" -1.0458403798561435     .13762606050904433               .0746    .0244608867175472                -.0019                      .                    .
14245 "EST" -1.7695510786217261    .017257325900497496               .1157    .0329611089718906                     .                      .  -.35852720170127134
14610 "EST"                  -2    -.01126126126126126               .1336     .040184895250876                     .    .015479072985126276    .3164968594186586
14976 "EST" -1.8860566476931633     .09847555633432627               .1313    .0574827981651377                     .     .06650770671889622  -.08414814973041197
15341 "EST" -2.0969100130080562     .17897591322379966               .1003    .0357191270164023                     .     .09206323858192285   .33696267646239475
15706 "EST" -2.3979400086720375     .33824922202678936  .11289999999999999    .0133499116549964                     .    -.03385245302332399    .3965595776786865
16071 "EST" -2.5228787452803374      .2291982610453948               .1025    .0304811107523412                     .     .07582866656576363    .4148200606592855
16437 "EST" -2.6989700043360187     .16186872840927785               .0803  .040797142319984596                     .     .09728474957794041    .7225144757462273
16802 "EST" -2.6989700043360187     .20678182075605267               .0591    .0443762042389211                     .     .10449387781268017   .11102914899403028
end
format %td Date

[Rich Goldstein]

in Stata, one cannot do arithmetic or algebra or ... on string variables; you can -tabulate- such variables; if you need to use a variable such as country in your data above, you will need to -encode- it; I strongly recommend setting up your labels first and then encoding; other than that, I don't follow what you want to do - maybe someone else can help; see

h encode

[Nick Cox]

The primary role of summarize is to provide summary statistics such as mean and SD, depending on options.

If you have a string variable that role is impossible to fulfil, but as a courtesy to users summarize doesn't throw you out if you ask for summarize results from string variables; it just shows 0 observations, which in this context (and several others in Stata) means there are no observations on which Stata can do what you ask with that variable.

You'd get the same result if you fed one or more string variables to (say) regress, even if you also fed some numeric variables at the same time.

[Daniel Schaefer]

there are no observations on which Stata can do what you ask with that variable.

This behavior is (perhaps surprisingly) entirely consistent with the rest of the language, where Stata routinely drops a subset of observations when they can't be used to preform an operation - usually when they contain missing data. The zero is just what you see when all of the cases are dropped. Some might call this a "silent error" but most of the time I'd rather the command completed execution (rather than halting on an error) because, for the initiated, partial results can be more informative about the underlying problem than a generic error message.

That said, this kind of thing confused the hell out of me more than once when I started learning the language a few years ago. I sympathize with the OP.

[Hemanshu Kumar]

Sky Emanuel I'm not sure what exactly you were hoping to achieve by using the summarize command on a string variable, but you might want to look into commands such as codebook or tabulate

For your data example, these commands would produce the following:

. codebook Country

------------------------------------------------------------------------------------------------------------------
Country                                                                                                (unlabeled)
------------------------------------------------------------------------------------------------------------------

                  Type: String (str3)

         Unique values: 5                         Missing "": 0/100

            Tabulation: Freq.  Value
                           23  "AUT"
                           23  "BEL"
                           23  "CYP"
                            8  "EST"
                           23  "HRV"

. tabulate Country

    Country |      Freq.     Percent        Cum.
------------+-----------------------------------
        AUT |         23       23.00       23.00
        BEL |         23       23.00       46.00
        CYP |         23       23.00       69.00
        EST |          8        8.00       77.00
        HRV |         23       23.00      100.00
------------+-----------------------------------
      Total |        100      100.00

[Sky Emanuel]

Thank you all for your help. I just wanted the number of observations of countries to be visible next to my numeric data.
Also, thanks Hemanshu Kumar , these commands gave me what I wanted.