These are data from the RAND Health Insurance Experiment (HIE). People who have read Mastering 'Metrics should recognize these data. They're featured prominently in that book and the authors' discussion of random assignment and experiments.

mm_randhie

## Format

The data are a list of two data frames (or "tibbles"). The first is the baseline data.

plantype

the plan coverage of the respondent, as a factor

age

the age of the respondent

blackhisp

whether the respondent is not white

cholest

the cholesterol level of the respondent (in mg/dl)

educper

the education-level of the respondent

female

whether the respondent is a woman

ghindx

a general health index

hosp

was the respondent hospitalized last year?

income1cpi

the family/household income of the respondent, adjusted for inflation

mhi

a mental health index

systol

the systolic blood pressure level of the respondent (in mm HG)

The second is the outcome data.

plantype

the plan coverage of the respondent, as a factor

ftf

the number of face-to-face visits for the respondent

out_inf

the total of out-patient expenses for the respondent

totadm

the number of hospital admissions for the respondent

tot_inf

the total health expenses for the respondent

## Source

RAND Health Insurance Experiment.

## Details

Data are already cleaned in a way that facilitates an easy replication of Table 1.3 and a partial replication of Table 1.4 in Mastering 'Metrics. Check http://www.masteringmetrics.com for more information. I want to note that my treatment of the data leans heavily on Jeff Arnold's treatment of it. Check https://jrnold.github.io/masteringmetrics/ for more information. Future updates to the data may pursue a more exhaustive replication. I will only note these data are a mess and the authors of Mastering 'Metrics do not do a great job annotating code.