# ccmean

##### Calculates estimates of the mean cost with censored data

This function calculates the mean cost for right-censored cost data over a period of L time units (days, months, years,...)

##### Usage

`ccmean(x, L = max(x$surv), addInterPol = 0)`

##### Arguments

- x
A dataframe with columns: id, cost, delta and surv. If Cost history is available it can be specified by: start and stop,

- L
Limit. Mean cost is calculated up till L, if not specified L = max(surv)

- addInterPol
This parameter affects the interpolation of cost between two observed times. Defaults to zero.

##### Details

The function returns four estimates. The first two are simple and biased downwards, and included for comparison. The estimates are:

- AS: "Available Sample estimator" - The simple sample mean

- CC: "Complete Case estimator" - The mean of fully observed cases

- BT: "Weighted Complete Case estimator" - Bang and Tsiatis's estimator

- ZT: "Weighted Available estimator" - Zhao and Tian's estimator

The function needs the following in a dataframe:

- id: The id separating each individual

- cost: The total cost, or if start and stop provided the specific cost

- start: Start of cost

- stop: End of cost, if one time cost then start = stop

- delta: Event variable, 1 = event, 0 = no event

- surv: Survival

##### Value

An object of class "ccobject".

##### References

Bang2000ccostr

Zhao2001ccostr

##### Examples

```
# NOT RUN {
hcost
ccmean(hcost, L = 1461, addInterPol = 1)
# }
```

*Documentation reproduced from package ccostr, version 0.1.0, License: MIT + file LICENSE*