Bioequivalence and Bioavailability Forum • Rounding

Rounding [Software]

posted by d_labes – Berlin, Germany, 2013-01-02 13:51 (4560 d 03:14 ago) – Posting: # 9777
Views: 13,492
(edited on 2013-01-03 09:31)

Hi Helmut!

❝ How does your software round?

I'm currently not in reach of my SAS but I strongly suppose that it will give 125.01 if one uses the ordinary ROUND() function. To be in accordance with the R method (or other software) one has to use the ROUNDE() function which rounds to even.

❝ Mine:

❝ Excel 2000: round(125.005, 2) → 125.01

Excel 2010: round(125.005,2) → 125.01
[edit]Just checked (03-Jan-2013)
SAS 9.2: round(125.005,0.01) → 125.01
(Note the definition of rounding to 2 decimals as rounding to multiples of 0.01)
[/edit]

❝ OO Calc: round(125.005, 2) → 125.01

❝ ...

❝ R 2.15.2: round(125.005, 2) → 125.00

Seems the R folks did it again the way different from what all others do :cool:

❝ In normal life not sooo important

A more drastically example, may be important also in normal life I think:

round(c(0.5,1.5,2.5,3.5,4.5,5.5),0)

[1] 0 2 2 4 4 6

At least in Germany one would expect:
[1] 1 2 3 4 5 6

❝ ... but in simulations. Example (10⁶ sim’s, empiric alpha ~ T/R 1.25 in conventional balanced cross-overs).

❝ n CV alpha alpha

❝ no rounding CI rounded

❝ 42 15% 0.049842 0.050746 (sig. >0.05)

❝ 36 17% 0.050010 0.050706 (sig. >0.05)

Wow! Seems rounding the CI anyhow is not such a good idea.
[edit]Also the rounding seems to be implied by regulatory definitions of the acceptance range as 80.00 - 125.00 (EMA & FDA)![/edit]

But ... IMHO this must be independent from the used rounding method for 5 except the magnitude of deviation from the not rounded results since all the other results >125.0000 - 125.0049 will be also counted as BE if rounded and as not BE if not rounded.

—
Regards,

Detlew

Complete thread:

Rounding Helmut 2013-01-01 16:51 [Software]
- Roundingd_labes 2013-01-02 12:51
  - Rounding Helmut 2013-01-04 17:35
    - Rounding d_labes 2013-01-05 19:25
      - Rounding Helmut 2013-01-05 20:13
        
        Sim’s are sim’s are sim’s d_labes 2013-01-05 20:57
      - Another vicious circle Helmut 2013-01-06 02:21
        
        Where all these numbers came from? d_labes 2013-01-07 15:52
        
        Flaw in the GL? Helmut 2013-01-07 17:29
        
        Flaw in the GL? d_labes 2013-01-08 11:44
        
        What a mess! Helmut 2013-01-08 19:08
        
        What a mess! d_labes 2013-01-09 10:33
        
        What a mess! Helmut 2013-01-09 15:18
- Rounding ElMaestro 2013-01-02 16:12
  - Abandon rounding Helmut 2013-01-02 17:04
- Rounding yjlee168 2013-01-05 23:15
  - Rounding Helmut 2013-01-06 03:29
  - Rounding Helmut 2013-01-06 15:34
    - Rounding yjlee168 2013-01-06 23:38