Bioequivalence and Bioavailability Forum • A little off topic: data.frame members

A little off topic: data.frame members [🇷 for BE/BA]

posted by yjlee168 – Kaohsiung, Taiwan, 2018-01-23 18:47 (2648 d 10:38 ago) – Posting: # 18279
Views: 5,456

Hi all,

I think we can use str() to preview all factors' name in a data.frame.

df <- sampleN.TOST(CV=0.3, theta0=0.95)

df$n

NULL

str(df)

'data.frame':   1 obs. of  9 variables:

 $ Design        : Factor w/ 1 level "2x2": 1

 $ alpha         : num 0.05

 $ CV            : num 0.3

 $ theta0        : num 0.95

 $ theta1        : num 0.8

 $ theta2        : num 1.25

 $ Sample size   : num 40

 $ Achieved power: num 0.816

 $ Target power  : num 0.8

There is no 'n' in df or sampleN.TOST(CV=0.3, theta0=0.95). So it returns NULL. If we do

df['Sample size']


  Sample size

1          40

df['Target power']


  Target power

1          0.8

sampleN.TOST(CV=0.3, theta0=0.95)['Sample size']  



+++++++++++ Equivalence test - TOST +++++++++++

            Sample size estimation

-----------------------------------------------

Study design:  2x2 crossover

log-transformed data (multiplicative model)



alpha = 0.05, target power = 0.8

BE margins = 0.8 ... 1.25

True ratio = 0.95,  CV = 0.3



Sample size (total)

 n     power

40   0.815845 



  Sample size

1          40

then it works.

❝ ...and therefore I can simply do this:

❝ sampleN.RSABE(CV=0.3, theta0=0.95)$n

❝ (the n column is baptised as "Sample size" but is still accessible via $n)

—
All the best,
-- Yung-jin Lee
bear v2.9.2:- created by Hsin-ya Lee & Yung-jin Lee
Kaohsiung, Taiwan https://www.pkpd168.com/bear
Download link (updated) -> here

Complete thread:

A little off topic: data.frame members ElMaestro 2018-01-22 23:49
- R-Inferno Helmut 2018-01-23 13:37
  - R-Inferno d_labes 2018-01-23 15:03
    - Thanks :-D ElMaestro 2018-01-23 15:26
      - Safe side syntax d_labes 2018-01-23 15:39
- A little off topic: data.frame membersyjlee168 2018-01-23 17:47