Bevor wir in R – oder auch in jedem anderen Statistik-Programm – arbeiten könnne, müssen wir unsere eifrig gesammelten Daten irgendwie ins Programm kriegen. In R war das für einige Datenformate lange Zeit eine schmerzhafte Angelegenheit, was das Arbeiten in R nicht gerade attraktiv gemacht hat. Das Tidyverse jedoch greift uns bei dieser Aufgabe unter die Arme und der Import ist mit einer Zeile Code (versprochen!) abgeschlossen.

Wir behandeln hier die gängigsten Datei-Typen: Comma-Separated Values (.csv), Excel-Dateien (.xlsx), SPSS-Dateien (.sav) und R-Objekt-Dateien (.rds). Jeder Datei-Typ hat seine Stärken und Schwächen, welche beim Import eine Rolle spielen können. CSV-Dateien sind eigentlich ideal zum Speichern von Daten, weil so ziemich jedes Programm, das mit Daten umgeht, entweder CSV-Daten einlesen, ausgeben oder abspeichern kann. Dabei werden die einzelnen Datenwerte durch Kommata getrennt abgespeichert (daher der Name). Jedes Komma zeigt also an, wann eine neue Spalte beginnt. Tricky wird es im deutschen Sprachraum, weil das Komma hier als Dezimaltrennzeichen genutzt wird. Die Zahl 1,5 würde also in 2 Spalten aufgeteilt werden. Da auch wir eine Daseinsberechtigung haben, und nicht alles ins englische Format überfüreh wollen, ist das Trennzeichen für CSV-Dateien bei uns kein Komma, sondern ein Semikolon (“;”).

Nach den CSV-Dateien werden wohl Excel-Dateien die am häufigsten verwendeten sein, wenn es um den Austausch von Daten geht. Natürlich kann man Excel-Dateien über “Speichern unter” als CSV abspeichern (etwas, das nach jeder Änderung dann immer wieder gemacht werden muss), aber den Schritt kann man sich sparen und direkt Excel-Dateien importieren.

Auch SPSS hat sein eigenes Datenformat, war ja klar. R hat sogar zwei, aber das RDS-Format bietet einige Vorteile, weshalb wir auch nur dieses behandeln.

Je nach Datei-Typ müssen wir unterschiedliche Pakete laden. Für CSV- und RDS-Dateien benötigen wir nur das Tidyverse. Für Excel-Dateien wird das Paket readxl verwendet, für SPSS-Dateien haven.

library(tidyverse)
library(readxl)
library(haven)

Im GitHub-Repository findest Du im Ordner “data” fünf Beispiel-Dateien (csv_data.csv, csv2_data.csv, excel_data.csv, spss_data.sav und rds_data.rds) in unterschiedlichen Formaten, mit denen wir den Daten-Import üben werden.

Comma-Separated Values (.csv)

International

CSV-Dateien importieren wir mit dem Befehl read_csv().

read_csv("data/csv_data.csv")
## Parsed with column specification:
## cols(
##   id = col_double(),
##   age = col_double(),
##   sex = col_character(),
##   group = col_character(),
##   test_score = col_double(),
##   bdi = col_double(),
##   well_being = col_double()
## )
## # A tibble: 530 x 7
##       id   age sex    group     test_score   bdi well_being
##    <dbl> <dbl> <chr>  <chr>          <dbl> <dbl>      <dbl>
##  1     1    24 Male   Waitlist        14.8     7         50
##  2     2    47 Male   Waitlist        19.0     4         25
##  3     3    24 Female Placebo         14.6     6         42
##  4     4    28 Female Waitlist        15.4     8         59
##  5     5    43 Male   Waitlist        16.2     3         12
##  6     6    25 Male   Treatment       22.0     8         20
##  7     7    22 Female Placebo         16.0     7         33
##  8     8    17 Female Treatment       22.4     5         14
##  9     9    44 Female Treatment       23.0     3         32
## 10    10    20 Female Waitlist        16.5     8         37
## # ... with 520 more rows

Zu Beginn kriegen wir eine Information dazu, wie R die Datei eingelesen hat. Es gibt nämlich mehrere Daten-Typen. read_csv() versucht nun selbst zu erraten, um welchen Daten-Typen sich in den Variablen verstecken und gibt seinen Vorschlag als Info ab. col_double() bedeutet, dass R diese Spalte als Zahl eingelesen hat, col_character() dass eine Spalte als Zeichenfolge behandelt wird.

Dieser Befehl öffnet jedoch nur die Datei. Um sie zu speichern, müssen wir sie einem Objekt zuweisen, dessen Namen wir frei wählen können.

csv_data <- read_csv("data/csv_data.csv")
## Parsed with column specification:
## cols(
##   id = col_double(),
##   age = col_double(),
##   sex = col_character(),
##   group = col_character(),
##   test_score = col_double(),
##   bdi = col_double(),
##   well_being = col_double()
## )
csv_data
## # A tibble: 530 x 7
##       id   age sex    group     test_score   bdi well_being
##    <dbl> <dbl> <chr>  <chr>          <dbl> <dbl>      <dbl>
##  1     1    24 Male   Waitlist        14.8     7         50
##  2     2    47 Male   Waitlist        19.0     4         25
##  3     3    24 Female Placebo         14.6     6         42
##  4     4    28 Female Waitlist        15.4     8         59
##  5     5    43 Male   Waitlist        16.2     3         12
##  6     6    25 Male   Treatment       22.0     8         20
##  7     7    22 Female Placebo         16.0     7         33
##  8     8    17 Female Treatment       22.4     5         14
##  9     9    44 Female Treatment       23.0     3         32
## 10    10    20 Female Waitlist        16.5     8         37
## # ... with 520 more rows

Wenn Du in RStudio arbeitest, wird dir aufgefallen sein, dass dir noch ein anderer, sehr ähnlich klingender Befehl vorgeschlagen wird, nämlich read.csv(). Das ist die Basis-Variante, die R nativ zur Verfügung stellt. Allerdings wird der Import relativ unübersichtlich dargestellt und wir erhalten ohne weiteres Zutun keine Informationen zu den Variablen-Typen.

read.csv("data/csv_data.csv")
##      id age    sex     group test_score bdi well_being
## 1     1  24   Male  Waitlist  14.830963   7         50
## 2     2  47   Male  Waitlist  18.951326   4         25
## 3     3  24 Female   Placebo  14.619546   6         42
## 4     4  28 Female  Waitlist  15.438800   8         59
## 5     5  43   Male  Waitlist  16.181193   3         12
## 6     6  25   Male Treatment  22.037545   8         20
## 7     7  22 Female   Placebo  15.983710   7         33
## 8     8  17 Female Treatment  22.366219   5         14
## 9     9  44 Female Treatment  23.026597   3         32
## 10   10  20 Female  Waitlist  16.530477   8         37
## 11   11  28   Male Treatment  14.598394   5         15
## 12   12  46 Female  Waitlist  18.594622   6         57
## 13   13  43   Male   Placebo  20.850671   4         31
## 14   14  48   Male Treatment  20.520692   7         19
## 15   15  32   Male Treatment  28.278799   2         21
## 16   16  45 Female Treatment  20.037016   4         40
## 17   17  30 Female   Placebo   9.963999   3         50
## 18   18  45   Male  Waitlist  14.552438   1         52
## 19   19  21   Male  Waitlist  15.447021   4         58
## 20   20  38 Female Treatment  17.896427   1         46
## 21   21  47   Male Treatment  22.458752   3         20
## 22   22  44   Male   Placebo  21.351758   1         13
## 23   23  36 Female   Placebo  14.896804   3         46
## 24   24  29 Female   Placebo  18.709113   3         22
## 25   25  45 Female  Waitlist  20.140872   6         22
## 26   26  48   Male   Placebo  17.808666   5         45
## 27   27  41 Female   Placebo  18.734497   5         14
## 28   28  49   Male Treatment  16.802089   5         41
## 29   29  30   Male Treatment  20.425132   1         39
## 30   30  48   Male  Waitlist  24.605413   4         57
## 31   31  30   Male  Waitlist  16.878033   3         19
## 32   32  20 Female Treatment  22.497833   5         59
## 33   33  45   Male   Placebo  14.416401   2         13
## 34   34  19   Male  Waitlist  24.052620   2         53
## 35   35  17   Male Treatment  25.681463   2         22
## 36   36  41   Male   Placebo  16.137472   9         15
## 37   37  49 Female  Waitlist  20.557112   1         24
## 38   38  18 Female   Placebo  20.312771   4         41
## 39   39  22   Male   Placebo  16.465839   2         47
## 40   40  27 Female Treatment  20.988159   3         40
## 41   41  44 Female Treatment  24.229824   3         41
## 42   42  42   Male   Placebo  15.449402   4         26
## 43   43  50 Female   Placebo  21.268919   3         35
## 44   44  32 Female Treatment  25.625651   8         16
## 45   45  20 Female   Placebo  18.058238   6         59
## 46   46  32 Female   Placebo  17.631963   1         24
## 47   47  33   Male  Waitlist  22.110356   8         18
## 48   48  32   Male   Placebo  19.083754   3         25
## 49   49  23   Male Treatment  15.371831   4         59
## 50   50  26   Male   Placebo  22.901227   4         46
## 51   51  44   Male  Waitlist  13.780166   3         56
## 52   52  47 Female Treatment  18.529491   3         47
## 53   53  47 Female Treatment  14.404215   3         36
## 54   54  27   Male   Placebo  19.129989   4         57
## 55   55  40   Male  Waitlist  18.903438   5         35
## 56   56  42 Female Treatment  23.578581   8         52
## 57   57  22   Male Treatment  18.987187  10         38
## 58   58  18 Female  Waitlist  16.601481   2         18
## 59   59  18   Male Treatment  18.519873   1         38
## 60   60  44   Male  Waitlist  15.646308   2         58
## 61   61  21   Male  Waitlist  18.543104   2         24
## 62   62  24   Male   Placebo  24.027461   1         33
## 63   63  40   Male  Waitlist  21.249020   4         52
## 64   64  38 Female Treatment  25.376193   3         13
## 65   65  43   Male  Waitlist  16.181173   2         59
## 66   66  17 Female   Placebo  22.969084   5         29
## 67   67  42   Male  Waitlist  16.807646   6         19
## 68   68  23   Male Treatment  23.436641   6         16
## 69   69  49   Male  Waitlist  17.557085   2         57
## 70   70  41 Female Treatment  30.308846  11         38
## 71   71  28   Male   Placebo  20.256123   4         51
## 72   72  17   Male  Waitlist  16.870011   4         44
## 73   73  46   Male Treatment  19.286927   1         29
## 74   74  19   Male Treatment  20.711221   7         15
## 75   75  29   Male Treatment  24.012376   1         39
## 76   76  23   Male Treatment  21.209376   2         22
## 77   77  31   Male  Waitlist  16.756785   3         25
## 78   78  36 Female Treatment  16.372833   0         40
## 79   79  16 Female  Waitlist  19.662887   4         18
## 80   80  40 Female  Waitlist  23.532984   4         34
## 81   81  50 Female Treatment  20.600158   1         41
## 82   82  38 Female  Waitlist  25.512852   3         57
## 83   83  24 Female Treatment  12.801259   8         44
## 84   84  38 Female Treatment  22.265600   6         51
## 85   85  40 Female Treatment  28.278386   6         39
## 86   86  42 Female   Placebo  19.677741   4         19
## 87   87  34   Male   Placebo  19.176906   3         55
## 88   88  48 Female  Waitlist  23.611693   4         41
## 89   89  29 Female  Waitlist  21.662897   2         57
## 90   90  39   Male Treatment  15.391568   3         21
## 91   91  42 Female   Placebo  15.188511   4         44
## 92   92  17   Male Treatment  22.202550   1         44
## 93   93  44 Female   Placebo  15.788929   3         14
## 94   94  49   Male Treatment  13.969373   5         14
## 95   95  46   Male Treatment  23.018800   9         20
## 96   96  46 Female   Placebo  17.933293   3         32
## 97   97  33 Female  Waitlist  21.673127   5         53
## 98   98  30 Female  Waitlist  11.932595   3         55
## 99   99  18 Female Treatment  21.858603   2         59
## 100 100  33   Male   Placebo  14.373729   4         60
## 101 101  40 Female   Placebo  17.519324   6         42
## 102 102  17   Male  Waitlist  20.009557  12         31
## 103 103  50   Male   Placebo  18.654740   2         20
## 104 104  39   Male   Placebo  25.991534   7         38
## 105 105  21 Female  Waitlist  23.607069   4         50
## 106 106  36 Female  Waitlist  18.910912   9         13
## 107 107  38 Female   Placebo  17.784416   7         19
## 108 108  48 Female  Waitlist  22.188541   2         26
## 109 109  36   Male Treatment  15.579388   1         59
## 110 110  17 Female  Waitlist  14.961379   7         14
## 111 111  24 Female Treatment  18.759443   6         54
## 112 112  21   Male Treatment  16.491228   3         59
## 113 113  33   Male  Waitlist  14.070121   4         21
## 114 114  49 Female  Waitlist  14.678054   3         17
## 115 115  35 Female  Waitlist  16.776493   4         33
## 116 116  19 Female Treatment  17.166675   3         51
## 117 117  30   Male   Placebo  14.959392   2         55
## 118 118  26 Female  Waitlist  16.345063   5         43
## 119 119  50 Female  Waitlist  24.255593   4         43
## 120 120  35   Male  Waitlist  22.930437   9         55
## 121 121  42 Female  Waitlist  22.914002   3         57
## 122 122  50 Female  Waitlist  20.155140   3         27
## 123 123  25 Female  Waitlist  23.323915   2         49
## 124 124  33   Male   Placebo  15.446671   2         55
## 125 125  41   Male   Placebo  23.644645   1         13
## 126 126  30   Male  Waitlist  24.649189   2         48
## 127 127  46   Male Treatment  26.058207   2         12
## 128 128  40   Male   Placebo  19.040639   5         44
## 129 129  29 Female   Placebo  23.001233   4         26
## 130 130  45 Female Treatment  15.738587   2         51
## 131 131  50   Male Treatment  16.838571   5         44
## 132 132  41   Male Treatment  21.184144   2         28
## 133 133  21 Female Treatment  23.467592   2         44
## 134 134  22 Female  Waitlist  20.336577   4         38
## 135 135  46 Female Treatment  24.611880   6         26
## 136 136  17 Female Treatment  13.752675   8         46
## 137 137  40   Male   Placebo  24.766789   2         13
## 138 138  29   Male Treatment  23.749299   2         44
## 139 139  43   Male  Waitlist  22.794793   6         25
## 140 140  26   Male  Waitlist  28.446327   2         12
## 141 141  23 Female Treatment  17.973373  13         34
## 142 142  46   Male   Placebo  23.963685   2         36
## 143 143  22   Male  Waitlist  11.514562   3         36
## 144 144  17   Male Treatment  15.901428  11         36
## 145 145  38   Male  Waitlist  12.755775   2         22
## 146 146  41 Female Treatment  22.384958   2         59
## 147 147  47 Female   Placebo  25.983820   3         31
## 148 148  33   Male Treatment  22.174039   7         55
## 149 149  45 Female  Waitlist  14.405200   3         44
## 150 150  26 Female Treatment  25.163400   9         53
## 151 151  26 Female  Waitlist  26.624734   3         27
## 152 152  31   Male Treatment  27.244304   4         40
## 153 153  35   Male  Waitlist  19.786399   3         39
## 154 154  49 Female  Waitlist  19.441433   3         48
## 155 155  48 Female   Placebo  17.253233   0         27
## 156 156  43 Female  Waitlist  21.523004   4         16
## 157 157  24 Female   Placebo  25.556499   2         32
## 158 158  45   Male   Placebo  18.618811   7         54
## 159 159  49 Female Treatment  15.918905   3         38
## 160 160  44   Male  Waitlist   8.417106   2         51
## 161 161  18   Male  Waitlist  11.556624  11         47
## 162 162  50 Female  Waitlist  19.767451   2         32
## 163 163  40 Female   Placebo  19.376419  10         43
## 164 164  48 Female Treatment  26.919202   3         21
## 165 165  22   Male Treatment  27.346637   6         52
## 166 166  46 Female Treatment  22.562643   4         13
## 167 167  16 Female   Placebo  24.853248   2         20
## 168 168  26   Male Treatment  22.911675   2         15
## 169 169  19 Female   Placebo  21.240379   4         14
## 170 170  18 Female  Waitlist  26.346302   1         18
## 171 171  41 Female   Placebo  21.784256   1         28
## 172 172  26 Female Treatment  12.233351   3         41
## 173 173  47 Female  Waitlist  23.818266   0         35
## 174 174  28   Male   Placebo  16.256383   2         45
## 175 175  33 Female   Placebo  20.522907   5         52
## 176 176  37   Male Treatment  10.670618  11         60
## 177 177  17   Male  Waitlist  18.074535   1         16
## 178 178  33   Male  Waitlist  21.044331   2         30
## 179 179  28   Male Treatment  16.082789   3         35
## 180 180  38 Female Treatment  28.038135   6         28
## 181 181  36 Female  Waitlist  18.438616   3         27
## 182 182  37 Female   Placebo  22.948672   4         52
## 183 183  37 Female Treatment  17.957416   2         57
## 184 184  16 Female Treatment  17.867703   5         24
## 185 185  24   Male Treatment  21.025227   7         28
## 186 186  29   Male  Waitlist  22.534694   3         50
## 187 187  22   Male Treatment  20.118505   7         20
## 188 188  25 Female  Waitlist  18.623502   6         43
## 189 189  31 Female Treatment  15.106704   9         22
## 190 190  36   Male   Placebo  13.173582   2         50
## 191 191  47   Male Treatment  22.607622   1         44
## 192 192  47   Male  Waitlist  16.533083   4         13
## 193 193  46   Male   Placebo  19.178714   4         14
## 194 194  18 Female Treatment  15.637437   2         14
## 195 195  36 Female  Waitlist  23.503519   2         37
## 196 196  24 Female  Waitlist  19.693115  10         36
## 197 197  19 Female Treatment  18.837736   4         23
## 198 198  48   Male  Waitlist  15.924889   8         14
## 199 199  43 Female Treatment  15.093246   2         41
## 200 200  36 Female  Waitlist  25.811519   9         52
## 201 201  38 Female  Waitlist  18.818594   0         38
## 202 202  49 Female Treatment  23.406162   4         22
## 203 203  41 Female  Waitlist  15.703774   2         44
## 204 204  32 Female   Placebo  17.606009   2         27
## 205 205  48 Female Treatment  16.508025   7         32
## 206 206  31   Male Treatment  19.163628   1         40
## 207 207  50   Male  Waitlist  20.086610   4         50
## 208 208  45 Female   Placebo  18.461053   8         54
## 209 209  36 Female   Placebo  22.770488   1         45
## 210 210  34   Male Treatment  29.122881  12         56
## 211 211  25 Female   Placebo  12.498740   3         60
## 212 212  25 Female  Waitlist  18.161649   4         30
## 213 213  43 Female Treatment  18.926686   0         46
## 214 214  33   Male   Placebo  18.422332   3         31
## 215 215  46 Female Treatment  16.713769   4         20
## 216 216  17 Female  Waitlist  20.016918   4         49
## 217 217  30   Male   Placebo  20.089724   4         34
## 218 218  29 Female  Waitlist  16.338159   1         24
## 219 219  38 Female Treatment  23.214371   2         22
## 220 220  17   Male Treatment  18.142627   2         36
## 221 221  39   Male Treatment  21.796199   7         55
## 222 222  31   Male   Placebo  15.416649   5         25
## 223 223  47   Male  Waitlist  20.014228   1         57
## 224 224  30 Female   Placebo  25.899107   2         34
## 225 225  38   Male   Placebo  24.501029   2         21
## 226 226  43   Male  Waitlist  19.407325   3         35
## 227 227  22   Male Treatment  16.789511   2         47
## 228 228  18 Female Treatment  19.443477   2         37
## 229 229  17 Female   Placebo  12.674474   4         40
## 230 230  22   Male   Placebo  20.994411   4         41
## 231 231  34   Male Treatment  20.535739   4         30
## 232 232  44   Male  Waitlist  21.127682   9         59
## 233 233  41   Male  Waitlist  22.350493  10         36
## 234 234  49   Male   Placebo  18.433091   8         28
## 235 235  22 Female Treatment  16.084158   6         54
## 236 236  30 Female Treatment  24.034050   4         48
## 237 237  43 Female Treatment  15.930302   3         22
## 238 238  31   Male Treatment  15.482508   4         37
## 239 239  37   Male Treatment  20.643968   1         25
## 240 240  46 Female  Waitlist  25.260506   5         35
## 241 241  27   Male  Waitlist  14.967710   6         13
## 242 242  35   Male Treatment  22.323641  10         49
## 243 243  28 Female  Waitlist  13.674219   6         19
## 244 244  45   Male   Placebo  16.138770   5         56
## 245 245  17   Male  Waitlist  23.056194   3         54
## 246 246  23 Female  Waitlist  25.782987   5         46
## 247 247  27 Female  Waitlist  23.714016   4         36
## 248 248  30   Male Treatment  24.234724   3         18
## 249 249  34 Female   Placebo  24.472456   1         53
## 250 250  32 Female   Placebo  14.575209   4         31
## 251 251  17   Male  Waitlist  22.606468   3         17
## 252 252  28   Male   Placebo  22.302954   4         53
## 253 253  26   Male Treatment  19.592365   1         45
## 254 254  33   Male   Placebo  16.349466   2         25
## 255 255  46 Female Treatment  15.399295   2         55
## 256 256  16   Male  Waitlist  17.311270   5         56
## 257 257  20   Male Treatment  26.961843   6         21
## 258 258  46   Male Treatment  23.029511   2         22
## 259 259  25   Male  Waitlist  27.502354   4         12
## 260 260  20 Female Treatment  20.693949   3         33
## 261 261  38   Male  Waitlist  11.364917   2         43
## 262 262  19   Male Treatment  14.765449   2         23
## 263 263  47 Female   Placebo  16.096061   1         51
## 264 264  33   Male   Placebo  19.314696  12         35
## 265 265  44 Female  Waitlist  16.159413   7         35
## 266 266  16 Female  Waitlist  16.349897  10         47
## 267 267  46   Male Treatment  19.599735   2         14
## 268 268  45   Male  Waitlist  32.860644   1         33
## 269 269  32   Male   Placebo  18.626982   3         15
## 270 270  37   Male Treatment  17.383294   4         55
## 271 271  27 Female   Placebo  22.561974   6         50
## 272 272  28 Female  Waitlist  17.171127   3         21
## 273 273  44   Male  Waitlist  17.014158   1         40
## 274 274  44   Male Treatment  19.365743   1         37
## 275 275  17   Male  Waitlist  17.872399   6         25
## 276 276  31 Female   Placebo  18.744161   5         58
## 277 277  45   Male   Placebo  28.264763   7         24
## 278 278  21 Female  Waitlist  18.310485  14         41
## 279 279  19 Female   Placebo  18.676856   5         51
## 280 280  39 Female  Waitlist  18.635505   0         39
## 281 281  31   Male   Placebo  24.305054   7         59
## 282 282  48   Male   Placebo  18.890847   1         18
## 283 283  25 Female   Placebo  18.346372   8         43
## 284 284  20 Female   Placebo  23.508046   2         54
## 285 285  44   Male Treatment  23.214027   3         55
## 286 286  24 Female   Placebo  18.240659   1         25
## 287 287  33   Male  Waitlist  20.709116   4         26
## 288 288  26   Male Treatment  18.723762   7         14
## 289 289  18   Male   Placebo  14.618085   5         42
## 290 290  33 Female Treatment  24.411021   0         43
## 291 291  41   Male Treatment  18.798679   5         37
## 292 292  43 Female   Placebo  22.288013   2         47
## 293 293  26 Female   Placebo  19.142059   2         15
## 294 294  48   Male  Waitlist  21.154569   6         35
## 295 295  31   Male   Placebo  16.432054   5         57
## 296 296  36 Female Treatment  14.840605   7         22
## 297 297  37 Female Treatment   8.760015   5         27
## 298 298  44   Male   Placebo  14.823664   4         58
## 299 299  36   Male Treatment  22.407812   3         35
## 300 300  42 Female Treatment  24.059178   2         34
## 301 301  33 Female  Waitlist  14.100200   1         22
## 302 302  21 Female   Placebo  19.318420   4         17
## 303 303  29   Male   Placebo  20.464117   1         33
## 304 304  46   Male  Waitlist  18.639818   1         44
## 305 305  28   Male   Placebo  17.558130   2         44
## 306 306  43   Male   Placebo  17.978751   6         26
## 307 307  16   Male  Waitlist  15.895145   5         42
## 308 308  40 Female Treatment  23.727966   2         41
## 309 309  30   Male  Waitlist  21.626574   8         46
## 310 310  42   Male   Placebo  26.581878   4         28
## 311 311  49 Female Treatment  23.226072   8         38
## 312 312  41 Female  Waitlist  23.818637   3         54
## 313 313  22   Male   Placebo  19.779562   5         59
## 314 314  41   Male Treatment  21.211374   2         22
## 315 315  34   Male  Waitlist  19.641161   2         41
## 316 316  33 Female   Placebo  14.911585   1         26
## 317 317  18   Male   Placebo  16.743648   4         36
## 318 318  32 Female  Waitlist  17.385372   8         53
## 319 319  19   Male   Placebo  13.984755   8         28
## 320 320  46   Male Treatment  14.252485   1         39
## 321 321  47 Female Treatment  20.525298   1         28
## 322 322  33   Male   Placebo  19.620226   1         34
## 323 323  49 Female   Placebo  16.663917   3         18
## 324 324  24   Male   Placebo  12.624144   3         18
## 325 325  39   Male  Waitlist  14.542458   3         30
## 326 326  34   Male  Waitlist  19.819747   2         59
## 327 327  26 Female  Waitlist  18.006327   4         29
## 328 328  32 Female   Placebo  16.109640   2         19
## 329 329  39   Male  Waitlist  26.432623   2         27
## 330 330  26   Male Treatment  17.251289   4         12
## 331 331  20   Male Treatment  20.228001   9         54
## 332 332  35 Female Treatment  15.610248   3         31
## 333 333  43 Female   Placebo  17.801031   3         42
## 334 334  46   Male  Waitlist  17.442469   6         20
## 335 335  40   Male  Waitlist  21.970990   7         49
## 336 336  48 Female   Placebo  15.554802   5         47
## 337 337  30 Female Treatment  25.379480   2         55
## 338 338  21   Male Treatment  22.374595   2         36
## 339 339  19   Male Treatment  17.002402   3         24
## 340 340  45   Male   Placebo  19.318473   6         40
## 341 341  24   Male Treatment  22.105080   4         18
## 342 342  16 Female   Placebo  29.868156   3         36
## 343 343  22 Female Treatment  19.455522   8         38
## 344 344  42   Male   Placebo  17.191076   1         50
## 345 345  42   Male  Waitlist  14.575737   2         42
## 346 346  22   Male  Waitlist  19.009582   4         57
## 347 347  34   Male  Waitlist  15.745884   1         43
## 348 348  32   Male Treatment  20.957702   4         30
## 349 349  18   Male  Waitlist  20.384087   8         20
## 350 350  16 Female   Placebo  18.906787   3         57
## 351 351  19   Male Treatment  13.117619   2         43
## 352 352  35 Female  Waitlist  11.882645   3         56
## 353 353  38 Female Treatment  16.642942   1         57
## 354 354  41   Male Treatment  18.794880   3         33
## 355 355  23   Male  Waitlist  22.982754   1         29
## 356 356  21   Male  Waitlist  11.383787  10         50
## 357 357  48 Female  Waitlist  25.316263   0         56
## 358 358  21   Male  Waitlist  23.380397   2         51
## 359 359  30   Male  Waitlist  20.356070   1         36
## 360 360  35 Female  Waitlist  16.071953   7         44
## 361 361  26   Male Treatment  21.717440   3         36
## 362 362  43 Female   Placebo  20.828541   2         36
## 363 363  42   Male  Waitlist  21.082850   3         23
## 364 364  17   Male   Placebo  20.842392   4         23
## 365 365  21   Male Treatment  17.627135  12         30
## 366 366  40 Female   Placebo  16.986252   1         28
## 367 367  16   Male  Waitlist  17.253229   5         51
## 368 368  45   Male Treatment  16.568988   4         26
## 369 369  30   Male  Waitlist  19.607241   7         12
## 370 370  42 Female   Placebo  18.344830   2         49
## 371 371  23 Female Treatment  20.085553   1         31
## 372 372  21   Male   Placebo  19.148417   0         30
## 373 373  41 Female Treatment  17.634751   3         26
## 374 374  31   Male  Waitlist  19.961565  11         38
## 375 375  16 Female  Waitlist  12.999709   3         31
## 376 376  31 Female Treatment  17.430922  13         28
## 377 377  29 Female  Waitlist  19.990137   9         46
## 378 378  26   Male   Placebo  17.346503   7         31
## 379 379  30   Male Treatment  18.457617   3         54
## 380 380  48 Female Treatment  21.006952   5         19
## 381 381  38   Male Treatment  19.588303  14         25
## 382 382  45 Female Treatment  24.215431   5         22
## 383 383  24   Male Treatment  24.519255   7         12
## 384 384  24 Female  Waitlist  21.390348   3         30
## 385 385  31   Male   Placebo  13.271511   4         52
## 386 386  47   Male Treatment  18.758939   4         31
## 387 387  23   Male   Placebo  23.994715   5         20
## 388 388  44 Female   Placebo  16.172913   1         33
## 389 389  41 Female   Placebo  17.819229   1         45
## 390 390  45   Male  Waitlist  20.878598   3         34
## 391 391  46   Male  Waitlist  23.991528   6         55
## 392 392  38   Male   Placebo  22.435910   4         21
## 393 393  37 Female   Placebo  17.803236   4         25
## 394 394  21 Female  Waitlist  28.388963   8         15
## 395 395  45   Male   Placebo  19.666196   4         47
## 396 396  49 Female   Placebo  24.355968   1         19
## 397 397  48 Female   Placebo  26.776802   4         52
## 398 398  50   Male  Waitlist  17.681042   2         26
## 399 399  20   Male  Waitlist  15.695848   2         23
## 400 400  42   Male Treatment  12.973797   2         16
## 401 401  17 Female  Waitlist  18.764214   3         37
## 402 402  22 Female Treatment  20.361118   5         49
## 403 403  40   Male   Placebo  12.505201   2         53
## 404 404  31   Male  Waitlist  17.072808   1         42
## 405 405  22   Male Treatment  14.385532   2         32
## 406 406  18   Male  Waitlist  17.622795   4         36
## 407 407  40   Male   Placebo  17.052711   4         24
## 408 408  26 Female   Placebo  23.240648   2         44
## 409 409  50   Male  Waitlist  17.698250   2         48
## 410 410  29 Female   Placebo  17.846933   6         57
## 411 411  44   Male  Waitlist  23.574470   8         31
## 412 412  26 Female Treatment  22.168653   3         14
## 413 413  21   Male  Waitlist  26.807460   9         24
## 414 414  19 Female  Waitlist  18.595558   0         57
## 415 415  30 Female   Placebo  15.601841   5         16
## 416 416  39   Male  Waitlist  16.706556   5         30
## 417 417  41 Female Treatment  17.931729   1         54
## 418 418  19 Female   Placebo  12.860965   3         16
## 419 419  48 Female  Waitlist  18.994352  11         33
## 420 420  26   Male  Waitlist  18.183840   5         28
## 421 421  18 Female   Placebo  24.411726   5         18
## 422 422  26 Female  Waitlist  21.664932   7         25
## 423 423  35 Female Treatment  24.971656   2         29
## 424 424  33 Female  Waitlist  21.578456   4         36
## 425 425  29   Male Treatment  18.626082   3         48
## 426 426  35   Male  Waitlist  17.942245   1         55
## 427 427  27 Female   Placebo  21.961905   6         19
## 428 428  35   Male Treatment  14.312453   6         28
## 429 429  20 Female  Waitlist  19.652386   5         34
## 430 430  37 Female  Waitlist  18.109733   1         15
## 431 431  50 Female   Placebo  13.354369   5         29
## 432 432  38 Female  Waitlist  22.229775   2         46
## 433 433  46   Male Treatment  25.066251   6         46
## 434 434  19   Male  Waitlist  20.046887   2         36
## 435 435  44   Male  Waitlist  25.409209   5         44
## 436 436  28   Male  Waitlist  14.160332   2         14
## 437 437  21   Male  Waitlist  22.110333   9         25
## 438 438  20 Female   Placebo  21.946626   1         13
## 439 439  38 Female  Waitlist  18.231621   5         26
## 440 440  27 Female Treatment  24.818577   1         34
## 441 441  30   Male  Waitlist  21.781023   1         42
## 442 442  31 Female   Placebo  18.509878   4         21
## 443 443  43   Male   Placebo  17.994107   2         38
## 444 444  28 Female Treatment  16.823179   2         27
## 445 445  18 Female Treatment  20.967382   2         20
## 446 446  39   Male   Placebo  12.001395  10         44
## 447 447  22 Female Treatment  14.509140  16         15
## 448 448  34   Male Treatment  11.609299  10         20
## 449 449  35   Male   Placebo  20.276881   7         52
## 450 450  43 Female Treatment  21.367308   5         13
## 451 451  21   Male Treatment  28.648329   3         38
## 452 452  49   Male  Waitlist  24.746938   3         31
## 453 453  31 Female   Placebo  23.077753   5         40
## 454 454  43 Female  Waitlist  21.973095   6         34
## 455 455  39   Male Treatment  20.917162   3         17
## 456 456  44   Male Treatment  21.387537   2         46
## 457 457  39   Male  Waitlist  21.154447   2         19
## 458 458  28 Female   Placebo  19.159983   4         34
## 459 459  29 Female  Waitlist  21.248572   2         38
## 460 460  32   Male Treatment  22.005122   3         25
## 461 461  46 Female  Waitlist  25.021638   4         38
## 462 462  30 Female   Placebo  21.769572   5         58
## 463 463  17 Female   Placebo  23.588788   1         30
## 464 464  27 Female Treatment  19.974765   6         27
## 465 465  25 Female   Placebo  12.377031   3         60
## 466 466  29   Male Treatment  24.215494   2         34
## 467 467  21 Female Treatment  17.410842   3         28
## 468 468  27   Male  Waitlist  16.932460   2         57
## 469 469  37   Male  Waitlist  20.807675   4         56
## 470 470  36 Female   Placebo  12.636720   7         43
## 471 471  48 Female Treatment  23.764568   1         32
## 472 472  36   Male  Waitlist  19.813318  11         49
## 473 473  36 Female Treatment  19.503054   6         42
## 474 474  19   Male   Placebo  20.826843   7         34
## 475 475  18   Male  Waitlist  26.741348   3         49
## 476 476  34   Male   Placebo  15.514271   1         17
## 477 477  18 Female  Waitlist  12.333065   6         23
## 478 478  22   Male   Placebo  20.687795   2         50
## 479 479  18 Female Treatment  16.211733  12         47
## 480 480  27   Male Treatment  16.746482   3         32
## 481 481  47   Male  Waitlist  13.731471   3         40
## 482 482  33   Male  Waitlist  19.851468   3         43
## 483 483  42   Male   Placebo  20.754198   1         17
## 484 484  40 Female Treatment  22.964284   3         21
## 485 485  48   Male  Waitlist  12.999226   1         36
## 486 486  27   Male  Waitlist  15.270534   5         36
## 487 487  30   Male Treatment  21.138963   2         28
## 488 488  29   Male  Waitlist  15.731455  13         53
## 489 489  34   Male   Placebo  17.605946   9         52
## 490 490  37   Male Treatment  15.919131   4         58
## 491 491  20 Female Treatment  25.566831   6         33
## 492 492  19 Female Treatment  20.907985   4         32
## 493 493  22   Male   Placebo  24.329630   5         32
## 494 494  31 Female  Waitlist  21.404479   1         54
## 495 495  46   Male   Placebo  22.384332   1         23
## 496 496  48   Male   Placebo  19.569929   2         45
## 497 497  16   Male Treatment  21.362089   3         37
## 498 498  28   Male  Waitlist  20.823564   2         55
## 499 499  32   Male   Placebo  17.790241  10         59
## 500 500  36   Male   Placebo  16.682421   5         28
## 501 501  19   Male  Waitlist  20.897070   1         30
## 502 502  25 Female Treatment  26.004790   4         34
## 503 503  42 Female Treatment  16.136324   3         20
## 504 504  34 Female  Waitlist  21.963424   7         36
## 505 505  32 Female  Waitlist  21.996091  11         15
## 506 506  39   Male  Waitlist  15.839340   1         35
## 507 507  33 Female   Placebo  18.501674   8         18
## 508 508  24   Male Treatment  22.778783   2         52
## 509 509  20   Male   Placebo  25.496369   5         40
## 510 510  21   Male Treatment  22.381152   6         40
## 511 511  37 Female Treatment  16.422991   1         51
## 512 512  37   Male Treatment  21.885998   3         34
## 513 513  31   Male  Waitlist  22.950648   3         39
## 514 514  29   Male  Waitlist  22.508998   7         55
## 515 515  25 Female   Placebo  26.954884   6         54
## 516 516  47 Female Treatment  23.129663   6         27
## 517 517  41 Female  Waitlist  24.696012   2         12
## 518 518  18   Male Treatment  18.386584   5         12
## 519 519  17 Female  Waitlist  16.726535   5         46
## 520 520  30   Male  Waitlist  22.869176   9         27
## 521 521  42 Female Treatment  10.648731   2         30
## 522 522  29   Male   Placebo  20.773746   4         53
## 523 523  50   Male Treatment  22.097858   6         22
## 524 524  24 Female   Placebo  20.782215  12         41
## 525 525  39 Female Treatment  19.184498   3         29
## 526 526  16 Female  Waitlist  20.632837   1         54
## 527 527  37 Female  Waitlist  13.438727   6         31
## 528 528  42 Female   Placebo  23.168809   3         47
## 529 529  28   Male  Waitlist  16.298207   2         43
## 530 530  41 Female   Placebo  24.077541   3         15

Deswegen kann man an dieser Stelle gerne im Tidyverse bleiben.

Deutschsprachiger Raum

Im deutschen Sprachraum (und auch noch in anderen Gebieten, in denen das Komma schon als Dezimaltrennzeichen verwendet wird) wird anstatt des Kommas das Semikolon zum Trennen von Werten genutzt. Wenn man sich die Datei in einem Text-Editor genauer anschaut, wird man genau das feststellen. Hat man eine solche Datei, nutzt man einfach read_csv2().

read_csv2("data/csv2_data.csv")
## Using ',' as decimal and '.' as grouping mark. Use read_delim() for more control.
## Parsed with column specification:
## cols(
##   id = col_double(),
##   age = col_double(),
##   sex = col_character(),
##   group = col_character(),
##   test_score = col_double(),
##   bdi = col_double(),
##   well_being = col_double()
## )
## # A tibble: 530 x 7
##       id   age sex    group     test_score   bdi well_being
##    <dbl> <dbl> <chr>  <chr>          <dbl> <dbl>      <dbl>
##  1     1    24 Male   Waitlist        14.8     7         50
##  2     2    47 Male   Waitlist        19.0     4         25
##  3     3    24 Female Placebo         14.6     6         42
##  4     4    28 Female Waitlist        15.4     8         59
##  5     5    43 Male   Waitlist        16.2     3         12
##  6     6    25 Male   Treatment       22.0     8         20
##  7     7    22 Female Placebo         16.0     7         33
##  8     8    17 Female Treatment       22.4     5         14
##  9     9    44 Female Treatment       23.0     3         32
## 10    10    20 Female Waitlist        16.5     8         37
## # ... with 520 more rows

Auch hier wieder nicht vergessen, den importierten Datensatz einem Objekt zuzuweisen!

Excel (.xlsx)

Excel-Dateien könnnen mit der Funktion read_excel() geöffnet werden.

read_excel("data/excel_data.xlsx")
## # A tibble: 530 x 7
##       id   age sex    group     test_score   bdi well_being
##    <dbl> <dbl> <chr>  <chr>          <dbl> <dbl>      <dbl>
##  1     1    24 Male   Waitlist        14.8     7         50
##  2     2    47 Male   Waitlist        19.0     4         25
##  3     3    24 Female Placebo         14.6     6         42
##  4     4    28 Female Waitlist        15.4     8         59
##  5     5    43 Male   Waitlist        16.2     3         12
##  6     6    25 Male   Treatment       22.0     8         20
##  7     7    22 Female Placebo         16.0     7         33
##  8     8    17 Female Treatment       22.4     5         14
##  9     9    44 Female Treatment       23.0     3         32
## 10    10    20 Female Waitlist        16.5     8         37
## # ... with 520 more rows

Auch hier wieder nicht vergessen, den importierten Datensatz einem Objekt zuzuweisen!

SPSS (.sav)

SPSS-Dateien können mit der Funktion read_spss() geöffnet werden.

read_spss("data/spss_data.sav")
## # A tibble: 530 x 7
##       id   age        sex         group test_score   bdi well_being
##    <dbl> <dbl>  <dbl+lbl>     <dbl+lbl>      <dbl> <dbl>      <dbl>
##  1     1    21 1 [Male]   1 [Waitlist]        19.5     6         37
##  2     2    18 2 [Female] 2 [Treatment]       25.1     1         32
##  3     3    37 1 [Male]   1 [Waitlist]        18.4     5         37
##  4     4    36 1 [Male]   1 [Waitlist]        18.4     6         55
##  5     5    45 1 [Male]   1 [Waitlist]        23.7     3         38
##  6     6    37 2 [Female] 3 [Placebo]         13.4     3         36
##  7     7    32 1 [Male]   2 [Treatment]       18.5     2         21
##  8     8    32 2 [Female] 3 [Placebo]         25.4     3         30
##  9     9    20 2 [Female] 2 [Treatment]       15.3     3         32
## 10    10    41 1 [Male]   1 [Waitlist]        20.1     1         16
## # ... with 520 more rows

Die Variablen sex und group sehen relativ komisch aus, weil hier anscheindn Zahlen und Worte abgespeichert wurden. In SPSS speichert man Faktoren, indem einem selbst gewähltem Faktor-Level ein -Label gegeben wird. Diese behält read_spss() freundlicherweise beide für uns (zu erkennen am Typ <dbl + lbl>), damit wir damit später selbst umgehen können.

R (.rds)

Das Beste kommt zum Schluss: RDS-Dateien können mit read_rds() geöffnet werden.

read_rds("data/rds_data.rds")
## # A tibble: 530 x 7
##       id   age sex    group     test_score   bdi well_being
##    <int> <dbl> <fct>  <fct>          <dbl> <dbl>      <dbl>
##  1     1    21 Male   Waitlist        19.5     6         37
##  2     2    18 Female Treatment       25.1     1         32
##  3     3    37 Male   Waitlist        18.4     5         37
##  4     4    36 Male   Waitlist        18.4     6         55
##  5     5    45 Male   Waitlist        23.7     3         38
##  6     6    37 Female Placebo         13.4     3         36
##  7     7    32 Male   Treatment       18.5     2         21
##  8     8    32 Female Placebo         25.4     3         30
##  9     9    20 Female Treatment       15.3     3         32
## 10    10    41 Male   Waitlist        20.1     1         16
## # ... with 520 more rows

Das Schöne an diesem Weg des Speicherns und Importierens ist, dass wir automatisch die korrekten Daten-Typen in den Variablen mit abgespeichert und eingelesen werden. Die Variablen sex und group sind nämlich Faktoren (zu erkennen am Typ <fct>), was durch das Einlesen des Datensatzes mit read_rds() berücksichtigt wurde. Wenn man noch einmal in die obigen Beispiele schaut, wird deutlich, dass das in allen anderen Methoden nicht geklappt hat. Teilt man Daten zwischen R-Nutzern, kann man das RDS-Format ohne weiteres ans Herz legen!