Reading the data
- Read the data dictionary for this simulated dataset to familiarise yourself with the variables.
Information: the data dictionary
The names of all other variables end in either .7 or .11 (depending whether they were measured at the age 7 clinic or the age 11 clinic)
male codes sex: 1=male, 0=female
age.yrs and age.yrs are the age (in decimal years) on the day of the clinic at age 7 or 11
ht is height in cm
ht.sit is sitting height in cm
ws is waist circumference in cm
hp is waist circumference in cm
wt is weight in Kg
sbp is systolic blood pressure (the top of the blood pressure fluctuation) measured (as is conventional) in mm of Hg (mercury)
dbp is diastolic blood pressure (the bottom of the blood pressure fluctuation) measured (as is conventional) in mm of Hg (mercury)
pulse is pulse rate measured in beats per minute
BMI is body mass index derived as wt/(ht/100)2 The height variable is divided by 100 to express it in metres rather than centimeters
- set the working directory using
setwdand read the dataset into R and assign it the variablesim.alspacusing theread.csvfunction - Look up the
colnamesfunction in the help file and apply it tosim.alspacto list all the column headings in the data. - Look up the
dimsfunction in the help file and apply it to tosim.alspacto get the dimensions of the dataset. Number of columns is the number of variables, number of rows is the number of participants.
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