loglikgeomRoy {bivgeom} R Documentation

## Log-likelihood function

### Description

Negative log-likelihood function for Roy's bivariate geometric model

### Usage

```loglikgeomRoy(par, x, y)
```

### Arguments

 `par` a vector containing the values of the three parameters θ_1, θ_2, and θ_3 `x` numeric vector of sample x-values (non-negative integers) `y` numeric vector of sample x-values (non-negative integers), same length as `x`

### Value

Value of the negative log-likelihood function

### Author(s)

Alessandro Barbiero

### References

Roy, D. (1993) Reliability measures in the discrete bivariate set-up and related characterization results for a bivariate geometric distribution, Journal of Multivariate Analysis 46(2), 362-373.

### See Also

`dbivgeomRoy`

### Examples

```theta1 <- 0.5
theta2 <- 0.7
theta3 <- 0.9
# random sample of size n=1000:
set.seed(12345)
n <- 1000
d <- rbivgeomRoy(n, theta1, theta2, theta3)
# parameter estimation, using the different proposed methods:
hattheta <- estbivgeomRoy(d[,1], d[,2], "ML")
loglikgeomRoy(hattheta, x=d[,1], y=d[,2])
# negative value of the (maximized) log-likelihood function
```

[Package bivgeom version 1.0 Index]