Set the same box width for BoxWhiskerChart

Question

I would like to use the same box width for two different plot. consider following example. How can I use the same box width for the second plot?

data = Table[RandomVariate[NormalDistribution[\[Mu], 1], 
    100], {\[Mu], {0, 3, 2, 5}}];

Multicolumn[{BoxWhiskerChart[data, AspectRatio -> 3], 
  BoxWhiskerChart[data[[;; 2]], AspectRatio -> 3]}]

Answer 1

Update: You can use a custom ChartElementFunction that takes bar widths as input:

ClearAll[cEF]
cEF[f_: "BoxWhisker", w_: .5] := {ChartElementData[f][{Mean @ #[[1]] +
    {-w, w}/2, #[[2]]}, ##2]} &

Examples:

SeedRandom[1]
data = Table[RandomVariate[NormalDistribution[μ, 1], 100], {μ, {0, 3, 2, 5}}];

Row[BoxWhiskerChart[data[[#]], ChartLabels -> #, 
    ChartElementFunction -> cEF["BoxWhisker", .5 (Length[#] + .5)/(Length[data] + .5)], 
    AspectRatio -> 3, ImageSize -> Medium, ChartStyle -> (ColorData[97] /@ #), 
    PlotRange -> {{0, Length[#] + .5}, MinMax[data]}] & /@ 
 {{1, 2, 3, 4}, {2}, {1, 3}, {1, 2, 4}}]

Row[BoxWhiskerChart[data[[#]], ChartLabels -> #, 
   ChartElementFunction -> cEF["GlassBoxWhisker", .9 (Length[#] + .5)/(Length[data] + .5)],
   AspectRatio -> 3, ImageSize -> Medium, 
   ChartStyle -> (ColorData[63, "ColorList"][[#]]), 
   PlotRange -> {{0, Length[#] + .5}, MinMax[data]}] & /@
  {{1, 2, 3, 4}, {2}, {1, 3}, {1, 2, 4}}]

Original answer:

Multicolumn[{BoxWhiskerChart[data, AspectRatio -> 3, 
   ImageSize -> Medium, PlotRange -> {-3, 8}], 
  BoxWhiskerChart[Join[{{}}, data[[;; 2]], {{}}], AspectRatio -> 3, 
   ImageSize -> Medium, PlotRange -> {-3, 8}]}]