![]() ![]() The reason for this, also guessed correctly by Nick, is precisely my despise of it when applying for situations where the SD should be selected instead (well underlined in a) and b) in #6. No wonder, he guessed my thoughts right, even when remarking about the - se - I should have demonstrated as well, for I preferred to choose the SD in the example I shared.Īctually, at first, my example presented both options, but I decided to avoid showing the SE for what I fear to be a somewhat misleading presentation in this particular case. Nick, as always, provided an insightful reply concerning the matter. I was curious about whether Marcos' example could be adapted to produce the execrable detonator or dynamite plots for consenting adults, and it can. ![]() Straight estimate +/- se or estimate +/- 2 * se bars seem to be used for one of more of the following reasons (a) tribal habit in some scientific fields (b) they look better in understating uncertainty (especially +/- se) (c) they are approximations to more precisely calculated confidence intervals. I suspect that the more statistically minded you are, the more you want confidence intervals. There is a larger and different issue that, on the whole, the users are ahead of the developers in programming what they want under this heading. It seems a bit untidy that you need collapse to produce sd (or semean, as Marcos could have shown) and ci to produce confidence intervals at specified confidence levels such as 95%, but dotplot, bar should be mentioned too. I just care here about how easy Stata is to use and the original post I think is guilty of exaggeration on this point. I (we, presumably) don't mind other programs being easy to use when they are. I think Bruce's example shows that SPSS is a bit (no, a lot) simpler here. The first is from the GRAPH command, the second from GGRAPH (i.e., the Chart Builder). Here are the plots showing means with 95% CIs. GUIDE: text.footnote(label("Error Bars: +/- 1 SD"))ĮND GPL.Note that all of these commands use the raw data. GRAPHDATASET NAME="graphdataset" VARIABLES=Foreign MEANSD(mpg, 1)[name="MEAN_mpg" * Plot mean & bars extending 1*SD below and ablve. GUIDE: text.footnote(label("Error Bars: +/- 1 SE")) GRAPHDATASET NAME="graphdataset" VARIABLES=Foreign MEANSE(mpg, 1)[name="MEAN_mpg" * Plot mean & bars extending 1*SE below and ablve. GUIDE: text.footnote(label("Error Bars: +/- 2 SE")) GRAPHDATASET NAME="graphdataset" VARIABLES=Foreign MEANSE(mpg, 2)[name="MEAN_mpg" * Plot mean & bars extending 2*SE below and ablve. GUIDE: text.footnote(label("Error Bars: 95% CI"))ĮLEMENT: interval(position(Foreign*MEAN_mpg), shape.interior(shape.square))ĮLEMENT: interval(position((Foreign*(LOW+HIGH))), shape.interior(shape.ibeam)) GUIDE: text.title(label("Simple Bar Mean of mpg by Foreign")) LOW="MEAN_mpg_LOW" HIGH="MEAN_mpg_HIGH"] MISSING=LISTWISE REPORTMISSING=NOĭATA: Foreign=col(source(s), name("Foreign"), unit.category())ĭATA: MEAN_mpg=col(source(s), name("MEAN_mpg"))ĭATA: LOW=col(source(s), name("MEAN_mpg_LOW"))ĭATA: HIGH=col(source(s), name("MEAN_mpg_HIGH")) GRAPHDATASET NAME="graphdataset" VARIABLES=Foreign MEANCI(mpg, 95)[name="MEAN_mpg" ![]() * Watch for the following functions: MEANCI(), MEANSE(), MEANSD(). * The new-fangled "Chart Builder" allows greater flexibility (at the cost of more code). GRAPH /ERRORBAR(STDDEV 1)=mpg BY Foreign. GRAPH /ERRORBAR(STERROR 1)=mpg BY Foreign. GRAPH /ERRORBAR(STERROR 2)=mpg BY Foreign. Code: * The "legacy" GRAPH command in SPSS.
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