We use describe, codebook, list, and count to describe variables to get a sense of our data.
describe produces a summary of the dataset, including its storage type, display format, value label and variable label.
If no variable is specified, describe will describe every variable in the dataset.
. sysuse auto
. describe m*
storage display value
variable name type format label variable label
-------------------------------------------------------------------
make str18 %-18s Make and Model
mpg int %8.0g Mileage (mpg)
codebook produces more information than describe does. It gives descriptive statistics for numeric variables and a sample of observations for string variables, in addition to the variable names, labels, and data type.
. sysuse auto
. codebook m*
---------------------------------------------------------------------------------------------------
make Make and Model
---------------------------------------------------------------------------------------------------
type: string (str18), but longest is str17
unique values: 74 missing "": 0/74
examples: "Cad. Deville"
"Dodge Magnum"
"Merc. XR-7"
"Pont. Catalina"
warning: variable has embedded blanks
---------------------------------------------------------------------------------------------------
mpg Mileage (mpg)
---------------------------------------------------------------------------------------------------
type: numeric (int)
range: [12,41] units: 1
unique values: 21 missing .: 0/74
mean: 21.2973
std. dev: 5.7855
percentiles: 10% 25% 50% 75% 90%
14 18 20 25 29
list lists values of the variables.
. sysuse auto
. list make-rep78 in 10/20 if price > 6000, table lists the values of the variables from make to rep78 from the 10th to 20th rows, whose prices are greater than 6000, in the form of a table.
+--------------------------------------+
| make price mpg rep78 |
|--------------------------------------|
11. | Cad. Deville 11,385 14 3 |
12. | Cad. Eldorado 14,500 14 2 |
13. | Cad. Seville 15,906 21 3 |
+--------------------------------------+
count counts the number of observations that satisfy the specified conditions.
. sysuse auto
. count in 10/20 if price > 6000 counts the number of observations from the 10th to 20th rows and whose prices are greater than 6000. We have 3 such cases in the sample.