Alvine Bissery wrote:
I need to calculate a AUC of "hem" with 8 time measurements
time hem
0 116
1 97
2 101
3 114
6 125
12 121
18 118
24 128
But I need only AUC above the threshold of hem=110
Ronan Conroy gave the solution, but:
... my problem is to create the new time variable, because time
values 1 and 2 have changed.
I need a new time variable (time_101)
time_110 hem_101
0 6
x1 0
x2 0
3 4
6 15
12 11
18 8
24 18
Where x1 is between 0 and 1 , and 1<x2<3
=====================================================
It is not clear to me why a new time variable is needed, but:
. generate time_110 = time
. replace time_110 = (time + time[_n+1])/2 if hem<110
. generate hem_110 = (hem-110)*(hem>110)
. list , clean
time hem time_110 hem_110
1. 0 116 0 6
2. 1 97 1.5 0
3. 2 101 2.5 0
4. 3 114 3 4
5. 6 125 6 15
6. 12 121 12 11
7. 18 118 18 8
8. 24 128 24 18
Hope this helps
Svend
________________________________________________________
Svend Juul
Institut for Folkesundhed, Afdeling for Epidemiologi
(Institute of Public Health, Department of Epidemiology)
Vennelyst Boulevard 6
DK-8000 Aarhus C, Denmark
Phone, work: +45 8942 6090
Phone, home: +45 8693 7796
Fax: +45 8613 1580
E-mail: [email protected]
_________________________________________________________
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