## Labour Training Evaluation Data

### Description

This `nsw74demo`

data frame, with 445 rows and 10 columns,
is the subset of the `nswdemo`

dataset for which 1974
earnings are available.
Data are for the male experimental control and treatment
groups, in an investigation of the effect of training
on changes, between 1974-1975 and 1978, in the earnings
of individuals who had experienced employment difficulties.

Likewise, `nsw74psid1`

(2675 rows) is the subset of the
`nswpsid1`

data, and `nsw74psid3`

(313 rows) is the subset of
the `nswpsid3`

data, for which 1974 income is available.
NB, also, the `nsw74psidA`

data set.

### Usage

```
data(nsw74demo)
data(nsw74psid1)
data(nsw74psid3)
data(nsw74psidA)
```

### Format

Columns are:

- trt
a numeric vector
identifying the study in which the subjects were enrolled
(0 = PSID, 1 = NSW).

- age
age (in years).

- educ
years of education.

- black
(0 = not black, 1 = black).

- hisp
(0 = not hispanic, 1 = hispanic).

- marr
(0 = not married, 1 = married).

- nodeg
(0 = completed high school, 1 = dropout).

- re74
real earnings in 1974.

- re75
real earnings in 1975.

- re78
real earnings in 1978.

### Details

The `nsw74psidA`

data set (252 rows) was obtained from
`nsw74psid1`

using:

`here <- age <= 40 & re74<=5000 & re75 <= 5000 & re78 < 30000`

`nsw74psidA <- nsw74psid1[here, ]`

### Source

http://www.columbia.edu/~rd247/nswdata.html

### References

Dehejia, R.H. and Wahba, S. 1999. Causal effects in
non-experimental studies: re-evaluating the evaluation of training
programs. Journal of the American Statistical Association 94:
1053-1062.

Lalonde, R. 1986. Evaluating the economic evaluations of
training programs. American Economic Review 76: 604-620.