Plain-language interpretation of a result

dmai_interpret() turns a result of the package into a short report: a headline, findings, recommendations and cautions, computed from its numbers, with the sources of the method. It covers dmai() (with as_dt = FALSE), dmai_compare(), dmai_user_cost() and dmai_moments().

Usage

dmai_interpret(x, top = 3L, ...)

# Default S3 method
dmai_interpret(x, top = 3L, ...)

# S3 method for class 'dmai_interpretation'
print(x, ...)

# S3 method for class 'dmai_interpretation'
format(x, style = c("text", "markdown"), width = getOption("width", 80L), ...)

Arguments

x: a result of a function of the package.
top: number of dates or components named in the findings (default 3).
...: unused.
style: "text" (default) or "markdown".
width: line width of the text (default getOption("width")).

Value

An object of class "dmai_interpretation": a list with analysis, title, headline, findings, recommendations, cautions, facts (the numbers behind the sentences), guide (how to read the method) and sources. format() gives it as text or Markdown.

Details

Growth per year is the average growth between the first and last dates, annualised with the spacing of the dates (monthly, quarterly, half-yearly or annual) when the date column is of class Date; otherwise growth is reported per period.

Author

Muhammad Yaseen (myaseen208@gmail.com)

Examples

data(money_sim)
fit <-
  dmai(
      .data     = money_sim
    , method    = "Barnett"
    , logbase   = NULL
    , date      = "Date"
    , x         = NULL
    , r         = NULL
    , user_cost = NULL
    , benchmark = "rb"
    , percent   = TRUE
    , base      = 100
    , as_dt     = FALSE
    )
dmai_interpret(
    x   = fit
  , top = 3
  )
#> Divisia (Barnett) monetary aggregate
#> 
#> From 2005-01-01 to 2024-12-01 the Divisia (Barnett) aggregate grew 11.3% a
#> year, against 12.8% for the simple sum (1.6 points less).
#> 
#> Findings:
#> - Largest growth at 2009-03-01, 2021-12-01, 2024-01-01 (2.49, 2.24, 2.17);
#>   smallest at 2007-06-01, 2012-09-01, 2018-12-01 (-0.71, -0.67, -0.61).
#> - At the last date the largest weights are x3 (28.1%), x1 (19.5%), x2
#>   (18.8%).
#> - The weights moved most for x1 (32.3 to 19.5%), x4 (4.3 to 9.9%), x6 (3.7 to
#>   8.5%).
#> - The simple sum overstates money growth: it gives the same weight to
#>   interest-bearing deposits, which are held largely as savings, as to
#>   currency and demand deposits.
#> 
#> Recommendations:
#> - Compare the methods with dmai_compare(); check how the result depends on
#>   the benchmark rate.
#> - dmai_moments() shows when the components grow at very different rates.
#> 
#> Sources:
#> - Barnett, W. A. (1978). The user cost of money. Economics Letters, 1(2),
#>   145-149. doi:10.1016/0165-1765(78)90051-4
#> - Barnett, W. A. (1980). Economic monetary aggregates: an application of
#>   index number and aggregation theory. Journal of Econometrics, 14(1), 11-48.
#>   doi:10.1016/0304-4076(80)90070-6
#> - Tornqvist, L. (1936). The Bank of Finland's consumption price index. Bank
#>   of Finland Monthly Bulletin, 10, 1-8.
#> - Theil, H. (1967). Economics and Information Theory. North-Holland,
#>   Amsterdam.