R Stargazer: How to combine dynamic cutoffs with fixed character vector in notes

Question

For some time already, I am stuck with the following problem, and slowly I am getting desperate because I am unable to find a solution to my problem. I am facing the following issue:

When producing HTML regression result tables with Stargazer, the notes section shows the significance cutoffs as follows:

*p**p***p<0.01

However, I would prefer a layout similar to the following:

Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’

I want to get this by extracting the cutoffs dynamically and combining with fixed character vectors. The Stargazer manual says:

> a character vector containing notes to be included below the table.
> The character strings can include special substrings that will be
> replaced by the corresponding cutoffs for statistical significance
> 'stars': [*], [**], and [***] will be replaced by the cutoffs, in
> percentage terms, for one, two and three 'stars,' respectively (e.g.,
> 10, 5, and 1). Similarly, [0.*], [0.**] and [0.***] will be replaced
> by the numeric value of cutoffs for one, two and three 'stars' (e.g.,
> 0.1, 0.05, and 0.01). [.*], [.**] and [.***] will omit the leading zeros (e.g., .1, .05, .01).

I now tried all possible combinations, but I always failed. I always end up with R outputting eg, [***] in the HTML file or throwing an error.

Could you help me figuring out the right code to combine fixed string values in the notes with dynamic cutoffs?

Answer 1

This is an interesting problem. After inspecting the code, I think the issue arises because the code that replaces [***] , [**] etc. with the appropriate cutoffs comes before the custom notes vector is applied (when it should come after). So, the solution would be to re-arrange the code so that it comes in the correct order. This requires a bit of code surgery. The following works for me; I am running stargazer_5.2 :

library(stargazer)

## Create new stargazer.wrap() to rearrange order of blocks
x <- capture.output(stargazer:::.stargazer.wrap)
idx <- c(grep("for \\(i in 1:length\\(\\.format\\.cutoffs\\)\\)", x)[2],
  grep("if \\(!is\\.null\\(notes\\)\\)", x),
  grep("if \\(!is\\.null\\(notes\\.align\\)\\)", x)[2])
eval(parse(text = paste0("stargazer.wrap <- ", paste(x[c(1:(idx[1] - 1), 
    (idx[2]):(idx[3] - 1), 
    idx[1]:(idx[2] - 1), 
    idx[3]:(length(x) - 1))], collapse = "\n"))))

## Create a new stargazer.() that uses our modified stargazer.wrap() function
x <- capture.output(stargazer)
x <- gsub(".stargazer.wrap", "stargazer.wrap", x)
eval(parse(text = paste0("stargazer. <- ", paste(x[-length(x)], collapse = "\n"))))

Results: First, before:

stargazer(lm(mpg ~ wt, mtcars), 
  type = "text",
  notes.append = FALSE,
  notes =  c("Signif. codes: 0 $***$ [.***] $**$ [.**] $*$ [.*]"))
# ===============================================================
#                                 Dependent variable:            
#                     -------------------------------------------
#                                         mpg                    
# ---------------------------------------------------------------
# wt                                   -5.344***                 
#                                       (0.559)                  

# Constant                             37.285***                 
#                                       (1.878)                  

# ---------------------------------------------------------------
# Observations                            32                     
# R2                                     0.753                   
# Adjusted R2                            0.745                   
# Residual Std. Error               3.046 (df = 30)              
# F Statistic                   91.375*** (df = 1; 30)           
# ===============================================================
# Note:               Signif. codes: 0 *** [.***] ** [.**] * [.*]

We have the problem, as you point out. Now, using our modified stargazer.() function (note the dot at the end):

stargazer.(lm(mpg ~ wt, mtcars), 
  type = "text",
  notes.append = FALSE,
  notes =  c("Signif. codes: 0 $***$ [.***] $**$ [.**] $*$ [.*]"))
# ========================================================
#                             Dependent variable:         
#                     ------------------------------------
#                                     mpg                 
# --------------------------------------------------------
# wt                               -5.344***              
#                                   (0.559)               

# Constant                         37.285***              
#                                   (1.878)               

# --------------------------------------------------------
# Observations                         32                 
# R2                                 0.753                
# Adjusted R2                        0.745                
# Residual Std. Error           3.046 (df = 30)           
# F Statistic                91.375*** (df = 1; 30)       
# ========================================================
# Note:               Signif. codes: 0 *** .01 ** .05 * .1