SnedecorCochran {bayesmeta} | R Documentation |
Artificial insemination of cows example data
Description
This data set gives means and (squared) standard errors of percentages of conceptions obtained from samples for six bulls.
Usage
data("SnedecorCochran")
Format
The data frame contains the following columns:
no | character | identifier |
n | numeric | sample size |
mean | numeric | mean |
var | numeric | variance (squared standard error) |
Details
Quoting from Snedecor and Cochran (1967), Sec. 10.18: “In research on artificial insemination of cows, a series of semen samples from a bull are sent out and tested for their ability to produce conceptions. The following data from a larger set kindly supplied by Dr. G. W. Salisbury, show the percentages of conceptions obtained from the samples for six bulls.”
Source
J. Hartung, G. Knapp, and B.K. Sinha. Statistical meta-analysis with applications. Wiley, Hoboken, NJ, USA, 2008.
References
G.W. Snedecor and W.G. Cochran. Statistical Methods. Iowa State University Press, Ames, IA, USA, 6th edition, 1967.
Examples
data("SnedecorCochran")
## Not run:
# analyze using uniform prior:
bma1 <- bayesmeta(y=SnedecorCochran[,"mean"],
sigma=sqrt(SnedecorCochran[,"var"]),
label=SnedecorCochran[,"no"],
tau.prior="uniform")
# analyze using Jeffreys prior:
bma2 <- bayesmeta(y=SnedecorCochran[,"mean"],
sigma=sqrt(SnedecorCochran[,"var"]),
label=SnedecorCochran[,"no"],
tau.prior="Jeffreys")
# compare results:
print(bma1)
print(bma2)
forestplot(bma1)
forestplot(bma2)
## End(Not run)