deleting observations

[Euslaner]

dropping data

II want to drop variables from a datset where there are ommissing values. I typed

. fre immfactor country if immfactor ~= .

immfactor -- takejobs crime strainwelfare owncustoms
---------------------------------------------------------------
| Freq. Percent Valid Cum.
------------------+--------------------------------------------
Valid -1.385437 | 3286 2.97 2.97 2.97
-1.375464 | 322 0.29 0.29 3.26
-1.36549 | 346 0.31 0.31 3.57
-1.355517 | 214 0.19 0.19 3.76
-1.345544 | 219 0.20 0.20 3.96
-1.335571 | 624 0.56 0.56 4.52
-1.325597 | 123 0.11 0.11 4.64
-1.315624 | 182 0.16 0.16 4.80
-1.313048 | 282 0.25 0.25 5.05
-1.305651 | 159 0.14 0.14 5.20
-1.303075 | 94 0.08 0.08 5.28
-1.295678 | 2527 2.28 2.28 7.56
-1.293101 | 97 0.09 0.09 7.65
-1.283128 | 46 0.04 0.04 7.69
-1.273155 | 35 0.03 0.03 7.72
-1.263182 | 86 0.08 0.08 7.80
-1.253208 | 35 0.03 0.03 7.83
-1.243261 | 104 0.09 0.09 7.93
-1.243235 | 48 0.04 0.04 7.97
-1.242571 | 80 0.07 0.07 8.04
: | : : : :
1.77834 | 43 0.04 0.04 96.08
1.779005 | 12 0.01 0.01 96.09
1.779031 | 45 0.04 0.04 96.13
1.788978 | 9 0.01 0.01 96.14
1.798951 | 12 0.01 0.01 96.15
1.808925 | 27 0.02 0.02 96.17
1.818898 | 6 0.01 0.01 96.18
1.828871 | 13 0.01 0.01 96.19
1.831447 | 1128 1.02 1.02 97.21
1.838844 | 14 0.01 0.01 97.22
1.841421 | 68 0.06 0.06 97.28
1.848818 | 43 0.04 0.04 97.32
1.851394 | 110 0.10 0.10 97.42
1.861367 | 128 0.12 0.12 97.54
1.87134 | 184 0.17 0.17 97.70
1.881314 | 623 0.56 0.56 98.27
1.891287 | 110 0.10 0.10 98.37
1.90126 | 144 0.13 0.13 98.50
1.911233 | 137 0.12 0.12 98.62
1.921207 | 1529 1.38 1.38 100.00
Total | 110759 100.00 100.00
---------------------------------------------------------------

country -- Country (ISO 3166-1 Numeric code)
--------------------------------------------------------------------------------
| Freq. Percent Valid Cum.
-----------------------------------+--------------------------------------------
Valid 8 Albania | 2486 2.24 2.24 2.24
31 Azerbaijan | 1448 1.31 1.31 3.55
40 Austria | 3008 2.72 2.72 6.27
51 Armenia | 2706 2.44 2.44 8.71
56 Belgium | 1488 1.34 1.34 10.05
70 Bosnia and Herzegovina | 2828 2.55 2.55 12.61
100 Bulgaria | 2218 2.00 2.00 14.61
112 Belarus | 2654 2.40 2.40 17.01
191 Croatia | 2681 2.42 2.42 19.43
196 Cyprus | 865 0.78 0.78 20.21
197 Northern Cyprus | 452 0.41 0.41 20.62
203 Czech Republic | 3242 2.93 2.93 23.54
208 Denmark | 4764 4.30 4.30 27.84
233 Estonia | 2451 2.21 2.21 30.06
246 Finland | 2166 1.96 1.96 32.01
250 France | 3138 2.83 2.83 34.85
268 Georgia | 2858 2.58 2.58 37.43
276 Germany | 4024 3.63 3.63 41.06
300 Greece | 1435 1.30 1.30 42.36
348 Hungary | 2785 2.51 2.51 44.87
: | : : : :
498 Moldova | 1211 1.09 1.09 58.48
499 Montenegro | 2184 1.97 1.97 60.45
528 Netherlands | 3668 3.31 3.31 63.76
578 Norway | 2169 1.96 1.96 65.72
616 Poland | 2453 2.21 2.21 67.93
620 Portugal | 2354 2.13 2.13 70.06
642 Romania | 2524 2.28 2.28 72.34
643 Russia | 2679 2.42 2.42 74.76
688 Serbia | 2559 2.31 2.31 77.07
703 Slovakia | 2565 2.32 2.32 79.38
705 Slovenia | 2235 2.02 2.02 81.40
724 Spain | 2455 2.22 2.22 83.62
752 Sweden | 2103 1.90 1.90 85.52
756 Switzerland | 4275 3.86 3.86 89.38
792 Turkey | 2069 1.87 1.87 91.24
804 Ukraine | 2420 2.18 2.18 93.43
807 North Macedonia | 2211 2.00 2.00 95.43
826 Great Britain | 3185 2.88 2.88 98.30
909 Northern Ireland | 435 0.39 0.39 98.69
915 Kosovo | 1447 1.31 1.31 100.00
Total | 110759 100.00 100.00
--------------------------------------------------------------------------------

.
. oneway immfactor country if immfactor ~= .,tab

Country |
(ISO 3166-1 | Summary of takejobs crime
Numeric | strainwelfare owncustoms
code) | Mean Std. Dev. Freq.
------------+------------------------------------
Albania | .52663247 .91669659 2,486
Azerbaij | .41242884 .75825759 1,448
Austria | -.34499898 .82297632 3,008
Armenia | .47523728 .74669216 2,706
Belgium | -.1342983 .75448219 1,488
Bosnia a | .04688463 .87830355 2,828
Bulgaria | -.23307162 .8599487 2,218
Belarus | -.02267476 .80367539 2,654
Croatia | .0175983 .85663715 2,681
Cyprus | -.56812984 .67338488 865
Northern | .23387116 1.0856686 452
Czech Re | -.41091566 .76977594 3,242
Denmark | -.04507802 .7441623 4,764
Estonia | -.08617654 .81005037 2,451
Finland | .06322009 .80574298 2,166
France | .26902951 .86031816 3,138
Georgia | .31850699 .93294149 2,858
Germany | -.16651872 .80024392 4,024
Greece | -.22786174 .81861355 1,435
Hungary | -.45008144 .79610421 2,785
Iceland | .47686534 .82023629 2,289
Ireland | -.2192179 .77487173 883
Italy | -.10612937 .83259777 3,303
Latvia | -.09514977 .74734859 2,348
Lithuani | -.16750899 .7170314 2,245
Luxembou | .26496319 .83185921 1,485
Malta | -.64797945 .60866197 1,308
Moldova | .12054501 .8428975 1,211
Monteneg | .22367822 .93590782 2,184
Netherla | .01379921 .75027059 3,668
Norway | -.03188767 .68567194 2,169
Poland | .12792221 .82211202 2,453
Portugal | .12159486 .7656805 2,354
Romania | .22670131 .96556158 2,524
Russia | -.24134028 .80454117 2,679
Serbia | -.06846114 .8731876 2,559
Slovakia | -.30673834 .7192112 2,565
Slovenia | -.01288831 .8123877 2,235
Spain | .26190901 .83062315 2,455
Sweden | .25258097 .87624981 2,103
Switzerl | .00209355 .77800164 4,275
Turkey | -.14600297 .84818332 2,069
Ukraine | .09837232 .85107846 2,420
North Ma | .18620844 1.0048139 2,211
Great Br | .04780672 .90185018 3,185
Northern | -.28429996 .76353595 435
Kosovo | -.17869994 .82166866 1,447
------------+------------------------------------
Total | -8.004e-10 .85779265 110,759

Analysis of Variance
Source SS df MS F Prob > F
------------------------------------------------------------------------
Between groups 6833.32589 46 148.550563 220.27 0.0000
Within groups 74663.3221 110712 .674392316
------------------------------------------------------------------------
Total 81496.648 110758 .735808231

Bartlett's test for equal variances: chi2(46) = 1.8e+03 Prob>chi2 = 0.000

. gen x = 1 if immfactor ~= .
(113,675 missing values generated)

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. drop * i x
i ambiguous abbreviation
r(111);

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. drop * if x
invalid syntax
r(198);

. drop * if x
invalid syntax
r(198);

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. drop * if x ~= 1
invalid syntax
r(198);

. fre x

x
-------------------------------------------------------
| Freq. Percent Valid Cum.
----------+--------------------------------------------
Valid 1 | 110759 49.35 100.00 100.00
Missing . | 113675 50.65
Total | 224434 100.00
-------------------------------------------------------

. replace x = 0 if x ~= 1
(113,675 real changes made)

. fre x

x
-----------------------------------------------------------
| Freq. Percent Valid Cum.
--------------+--------------------------------------------
Valid 0 | 113675 50.65 50.65 50.65
1 | 110759 49.35 49.35 100.00
Total | 224434 100.00 100.00
-----------------------------------------------------------

. drop * if x == 0
invalid syntax
r(198);

. drop immfator if x == 0
variable immfator not found
r(111);

. drop immfactor if x == 0
invalid syntax
r(198);

. drop immfactor if x ~= 1
invalid syntax
r(198);

This seems to follow the manualbut I cannot delete the observations. What did I do wrong? Any help would be appreciated, Thanks,

Ric Uslaner
.

[George Ford]

drop if mi(immfactor)?

[Nick Cox]

Nothing in your code that evokes an error message follows the manual.

You can drop observations OR you can drop variables, but you can't drop both at the same time. That doesn't make sense to Stata. Chopping at rows and columns of a dataset simultaneously isn't allowed. Chopping at rows and columns in sequence might make sense, but doesn't seem to me what you want any way.

* can only be a wildcard for all variables.

immfactor is a single variable name

if x ~= 1 (for example) specifies zero or more observations of a variable x

and so on.

It's hard to follow your code. It would help if you used CODE mark-up and deleted commands that fail because of typos obvious to you.

My guess is that you want

drop if immfactor == .

-- but if this guess is correct then you want to drop observations, not variables.