[R-meta] Ratio of Means

[Viechtbauer Wolfgang (SP)]

Also, I cannot reproduce this problem.

library(metafor)

arm.df <- read.table(header=TRUE, text = "
id            study group  mean    sd   n
1        Arici 2009   Exp 35.73  5.24  27
2        Arici 2009   Ctl 62.93  8.67  27
3       Arslan 2011   Exp  4.25  2.03  20")

escalc(measure='MNLN', mi=mean, sdi=sd, ni=n) ### this obviously fails since the variables cannot be found

escalc(measure='MNLN', mi=mean, sdi=sd, ni=n, data=arm.df) ### works

attach(arm.df)
escalc(measure='MNLN', mi=mean, sdi=sd, ni=n) ### also works, but don't use attach (shudder)
detach(arm.df)

Best,
Wolfgang

-----Original Message-----
From: Michael Dewey [mailto:lists at dewey.myzen.co.uk] 
Sent: Friday, July 21, 2017 13:01
To: Nathan Pace; Viechtbauer Wolfgang (SP); r-sig-meta-analysis at r-project.org
Subject: Re: [R-meta] Ratio of Means

Dear Nathan

Try using the data parameter rather than attaching arm.df.
Alternatively call the standard deviation something other than sd.

On 20/07/2017 22:17, Nathan Pace wrote:
> Hi,
>
> Thanks for the pointers and links.
>
> Next problem is using the measure = “MNLN” in escalc.
>
> I created the 2k data frame.
>
>> arm.df
>               study group  mean    sd   n
> 1        Arici 2009   Exp 35.73  5.24  27
> 2        Arici 2009   Ctl 62.93  8.67  27
> 3       Arslan 2011   Exp  4.25  2.03  20
> 4       Arslan 2011   Ctl 11.25  5.03  20
> 5       Arslan 2013   Exp  5.15  4.29 100
> 6       Arslan 2013   Ctl   9.1  4.68 100
> 7      Aydogan 2008   Exp  0.27  0.08  40
> 8      Aydogan 2008   Ctl  0.35  0.09  40
> 9        Cakan 2008   Exp    11     2  20
> 10       Cakan 2008   Ctl    12     2  20
> 11       Cobby 1999   Exp    35  20.4  24
> 12       Cobby 1999   Ctl  54.9  28.3  21
> 13        Dahl 1997   Exp  21.2  7.88  22
> 14        Dahl 1997   Ctl  18.7   5.9  21
> 15      Dilmen 2010   Exp  18.1 13.93  20
> 16      Dilmen 2010   Ctl    30 11.32  19
> 17      Durmus 2007   Exp  30.5 11.55  25
> 18      Durmus 2007   Ctl 42.74 12.33  25
> 19        Emir 2010   Exp  7.65  0.78  30
> 20        Emir 2010   Ctl  13.8  2.26  30
> 21       Fayaz 2004   Exp    12     6  17
> 22       Fayaz 2004   Ctl    22    13  17
> 23      Jokela 2010   Exp 38.85  16.8  40
> 24      Jokela 2010   Ctl 45.15  18.9  40
> 25     Khalili 2013   Exp     3  2.28  25
> 26     Khalili 2013   Ctl   4.2  1.57  25
> 27  Kilieaslan 2010   Exp 20.56   0.4  25
> 28  Kilieaslan 2010   Ctl  28.6  0.35  25
> 29     Koppert 2006   Exp    17    22  25
> 30     Koppert 2006   Ctl    38    22  25
> 31    Kvalsvik 2003   Exp    16     5  30
> 32    Kvalsvik 2003   Ctl    20     6  30
> 33  Montgomery 1996   Exp  27.1    27  19
> 34  Montgomery 1996   Ctl  34.5  15.1  20
> 35        Moon 2011   Exp   8.7   5.4  36
> 36        Moon 2011   Ctl  12.6   6.9  35
> 37 Munishankar 2008   Exp  33.8  23.8  25
> 38 Munishankar 2008   Ctl  44.1  24.4  25
> 39     Sinatra 2005   Exp  38.3  35.1  49
> 40     Sinatra 2005   Ctl  57.4  52.3  52
> 41        Syal 2010   Exp  9.53  1.88  30
> 42        Syal 2010   Ctl 10.19  2.08  30
> 43      Toygar 2008   Exp  16.5  11.1  30
> 44      Toygar 2008   Ctl  34.3  11.8  30
> 45      Yalcin 2012   Exp 48.53  12.4  26
> 46      Yalcin 2012   Ctl 73.03 22.41  27
>
> The call to escalc returned an error:
>
>> arm.df <- escalc(measure = 'MNLN', mi = mean, sdi = sd, ni = n)
> Error in sdi < 0 :
>   comparison (3) is possible only for atomic and list types
>
> ?????
>
> Nathan