reliaR (version 0.01)

qq.chen: Quantile versus quantile (QQ) plot for the Chen distribution

Description

The function qq.chen() produces a QQ plot for the Chen based on their MLE or any other estimator. Also, a line going through the first and the third quartile can be sketched.

Usage

qq.chen(x, beta.est, lambda.est, main = " ", line.qt = FALSE, ...)

Arguments

x

vector of observations

beta.est

estimate of the parameter beta

lambda.est

estimate of the parameter lambda

main

the title for the plot

line.qt

logical; if TRUE, a line going by the first and third quartile is sketched.

...

additional arguments to be passed to the underlying plot function.

Value

The function qq.chen() carries out a QQ plot for the Chen

References

Castillo, E., Hadi, A.S., Balakrishnan, N. and Sarabia, J.M.(2004). Extreme Value and Related Models with Applications in Engineering and Science, John Wiley and Sons, New York.

Chen, Z.(2000). A new two-parameter lifetime distribution with bathtub shape or increasing failure rate function, Statistics and Probability Letters, 49, 155-161.

Pham, H.(2006). System Software Reliability, Springer-Verlag.

See Also

pp.chen for PP plot and ks.chen function;

Examples

## Load data sets
data(sys2)
## Maximum Likelihood(ML) Estimates of beta & lambda for the data(sys2)
## beta.est = 0.262282404, lambda.est = 0.007282371

qq.chen(sys2, 0.262282404, 0.007282371, line.qt = FALSE)