Jacob Liljehult
Klinisk sygeplejespecialist
cand.scient.san, Ph.d.
Neurologisk afdeling
Nordsjællands Hospital
Hvis man ønsker at tælle hvor mange der er i hver gruppe kan man bruge funktionen table()
eller
summary()
(de giver samme output):
table(strokedata$diagnosis)
table(strokedata$inhospmors)
ICH | IS |
---|---|
110 | 921 |
Alive | Dead |
971 | 60 |
Man kan også lave en 2 x 2 table:
with(strokedata, table(diagnosis, inhospmors))
inhospmors | ||
---|---|---|
diagnosis | Alive | Dead |
ICH | 88 | 22 |
IS | 883 | 38 |
For at få procenter bruges funktionen prop.table()
with(strokedata, prop.table(table(diagnosis, inhospmors)))
inhospmors | ||
---|---|---|
diagnosis | Alive | Dead |
ICH | 0.08535403 | 0.02133851 |
IS | 0.85645005 | 0.03685742 |
with(strokedata, prop.table(table(diagnosis, inhospmors) ,1)) # Procent for rækker
with(strokedata, prop.table(table(diagnosis, inhospmors) ,2)) # Procent for koloner
inhospmors | ||
---|---|---|
diagnosis | Alive | Dead |
ICH | 0.8000000 | 0.2000000 |
IS | 0.9587405 | 0.0412595 |
inhospmors | ||
---|---|---|
diagnosis | Alive | Dead |
ICH | 0.09062822 | 0.36666667 |
IS | 0.90937178 | 0.63333333 |