{smcl}
{.-}
help for {cmd:reghintfe} {right:()}
{.-}
 
{title:Title}

reghintfe - Estimates a linear regression model with one interacted high dimensional fixed effect.

{title:Syntax}

{p 8 15}

{cmd:reghintfe} {it:{help depvar}} [{it:{help indepvar}}] [{help if}] [{help in}] , {cmd:id1(}{it:{help varname}}{cmd:)} {cmd:intvar(}{it:{help varname}}{cmd:)} [{it:options}] 

{p 8 15}


{title:Description}

{p} This command estimates a linear regression model with one high-dimensional interacted fixed effect. The command
makes use of the Frisch-Waugh-Lovell result to avoid computing the dummy variables and the interactions for the fixed effects.
Because of this it can be used with a very large number of groups for the fixed effect.

{title:Options}

{p 0 4} {cmd:id1(}{it:{help varname}}{cmd:)} fixed effect variable. This option is required.

{p 0 4} {cmd:intvar(}{it:{help varname}}{cmd:)} variables that interact with the fixed effect. This option is required.

{p 0 4} {cmd:cluster(}{it:varname}{cmd:)} computes clustered standard errors. 

{p 0 4}{cmdab:verb:ose} gives more information during estimation.

{title:Examples}

Example 1:
Estimates a model with interaction between a fixed effect i and the variable x3.
Does the same as "regress y x1 x2 i.j##c.x3"

{p 8 16}{inp:. regintfe y x1 x2, id1(j) intvar(x3)}{p_end}
 
It creates two variables, __fe0 and __fe1. The variable __fe0 contains the estimates of the coefficients for the 
fixed effect and the variable __fe1 the estimates of the coefficients for the interaction between "j" and "x3".

Example 2:
Estimates a model with interaction between a fixed effect i and the variables x2 and x3. Standard errors are clustered on "j".
Does the same as "regress y x1 i.j##c.x2 i.j##c.x3, cluster(j)"

{p 8 16}{inp:. regintfe y x1, id1(j) intvar(x2 x3)} cluster(j) {p_end}
 
Creates three variables,  __fe0, __fe1 and __fe2. The variable __fe0 contains the estimates of the coefficients for the 
fixed effect, the variable __fe1 the estimates of the coefficients for the interaction between "j" and "x2" and
the variable __fe2 the estimates of the coefficients for the interaction between "j" and "x3".

{title:Author}

{p}
Paulo Guimaraes, Universidade do Porto, Portugal.

{p}
Email: {browse "mailto:pguimaraes@fep.up.pt":pguimaraes@fep.up.pt}

Comments welcome!

{title:Reference}

If you use this program in your research cite:

Paulo Guimaraes and Pedro Portugal. "A Simple Feasible Alternative Procedure to Estimate Models with 
High-Dimensional Fixed Effects", Stata Journal, 10(4), 628-649, 2010.

{p_end}