Hi Michael This looks like it could be really helpful in moving my project forwards thank you. I remember many years ago using (proprietary) software from the University of Liverpool which did a nice job of allowing regions to be defined, and then for the space to be rotated to obtain visual inspection of relative distance from different angles. I appreciate that smacof will not do that, but as long as the analysis allows for the graph to be plotted and analysed, that's what's important. Thank you again, and to all of those who responded. Best wishes Andrew On 21/09/18 14:07, Michael Friendly wrote:> Smallest space analysis (SSA) is just the name given to software > developed by Guttman & Lingoes around the time the various versions > of multidimensional scaling were being developed.? Call it Israeli MDS > or Falafel MDS if you prefer. The reason you encountered it in your > course is presumably that the instructor was trained in that. > > There are several variants of MDS-like algorithms for embedding > points representing objects in a space, using data representing > similarities or distances among objects -- metric (cmdscale) > and non-metric (MASS::isoMDS), using only rank order information, and > a variety of > measures of goodness-of-fit ("stress").? I don't recall the details > of the SSA programs, but that should matter little conceptually. > > The smacof package offers the widest array of possibilities. > > -Michael > > > On 9/19/2018 7:00 AM, Andrew wrote: >> Hi >> >> As part of my forensics psych course, we have been introduced to >> Guttman's smallest space analysis (SSA). I want to explore this approach >> using R, but despite finding some queries on the web about this same >> thing, have yet to find any answers. The MASS package doesn't seem to do >> the job, and the only thing I have been able to find is some proprietary >> software HUDAP? (Hebrew University Data Analysis Package) which may/ not >> be compatible with R (or GNU/Linux for that matter). >> >> Does anyone have information on how to do SSA using R? >> >> Many thanks >> >> Andrew >> >> >> ????[[alternative HTML version deleted]] >> > >
On 9/22/2018 6:49 AM, Andrew wrote:> Hi Michael > > This looks like it could be really helpful in moving my project forwards > thank you. > > I remember many years ago using (proprietary) software from the > University of Liverpool which did a nice job of allowing regions to be > defined, and then for the space to be rotated to obtain visual > inspection of relative distance from different angles. I appreciate that > smacof will not do that, but as long as the analysis allows for the > graph to be plotted and analysed, that's what's important.You need not rely on the plots provided directly by a given package. Just roll your own using standard plotting libraries. Here is just the first Google hit on "R MDS 3D plot" http://omnilogia.blogspot.com/2014/05/basic-2d-3d-multi-dimensional-scaling.html which shows a rotating 3D plot, colored by a grouping variable. Here is another: http://whatzcookinlab.blogspot.com/2013/05/spinning-3d-mds-plot.html The vegan and ade4 packages also have a variety of plots and related methods. -Michael> > Thank you again, and to all of those who responded. > > Best wishes > Andrew > > > On 21/09/18 14:07, Michael Friendly wrote: >> Smallest space analysis (SSA) is just the name given to software >> developed by Guttman & Lingoes around the time the various versions >> of multidimensional scaling were being developed.? Call it Israeli MDS >> or Falafel MDS if you prefer. The reason you encountered it in your >> course is presumably that the instructor was trained in that. >> >> There are several variants of MDS-like algorithms for embedding >> points representing objects in a space, using data representing >> similarities or distances among objects -- metric (cmdscale) >> and non-metric (MASS::isoMDS), using only rank order information, and >> a variety of >> measures of goodness-of-fit ("stress").? I don't recall the details >> of the SSA programs, but that should matter little conceptually. >> >> The smacof package offers the widest array of possibilities. >> >> -Michael >> >> >> On 9/19/2018 7:00 AM, Andrew wrote: >>> Hi >>> >>> As part of my forensics psych course, we have been introduced to >>> Guttman's smallest space analysis (SSA). I want to explore this approach >>> using R, but despite finding some queries on the web about this same >>> thing, have yet to find any answers. The MASS package doesn't seem to do >>> the job, and the only thing I have been able to find is some proprietary >>> software HUDAP? (Hebrew University Data Analysis Package) which may/ not >>> be compatible with R (or GNU/Linux for that matter). >>> >>> Does anyone have information on how to do SSA using R? >>> >>> Many thanks >>> >>> Andrew >>> >>> >>> ????[[alternative HTML version deleted]] >>> >> >> >
Ha! Even better - thank you. Plenty here for me to play around with. Many thanks Andrew On 23/09/18 15:22, Michael Friendly wrote:> On 9/22/2018 6:49 AM, Andrew wrote: >> Hi Michael >> >> This looks like it could be really helpful in moving my project >> forwards thank you. >> >> I remember many years ago using (proprietary) software from the >> University of Liverpool which did a nice job of allowing regions to >> be defined, and then for the space to be rotated to obtain visual >> inspection of relative distance from different angles. I appreciate >> that smacof will not do that, but as long as the analysis allows for >> the graph to be plotted and analysed, that's what's important. > > You need not rely on the plots provided directly by a given package. > Just roll your own using standard plotting libraries. > Here is just the first Google hit on "R MDS 3D plot" > > http://omnilogia.blogspot.com/2014/05/basic-2d-3d-multi-dimensional-scaling.html > > > which shows a rotating 3D plot, colored by a grouping variable. Here > is another: > > http://whatzcookinlab.blogspot.com/2013/05/spinning-3d-mds-plot.html > > The vegan and ade4 packages also have a variety of plots and related > methods. > > > -Michael > >> >> Thank you again, and to all of those who responded. >> >> Best wishes >> Andrew >> >> >> On 21/09/18 14:07, Michael Friendly wrote: >>> Smallest space analysis (SSA) is just the name given to software >>> developed by Guttman & Lingoes around the time the various versions >>> of multidimensional scaling were being developed.? Call it Israeli MDS >>> or Falafel MDS if you prefer. The reason you encountered it in your >>> course is presumably that the instructor was trained in that. >>> >>> There are several variants of MDS-like algorithms for embedding >>> points representing objects in a space, using data representing >>> similarities or distances among objects -- metric (cmdscale) >>> and non-metric (MASS::isoMDS), using only rank order information, >>> and a variety of >>> measures of goodness-of-fit ("stress").? I don't recall the details >>> of the SSA programs, but that should matter little conceptually. >>> >>> The smacof package offers the widest array of possibilities. >>> >>> -Michael >>> >>> >>> On 9/19/2018 7:00 AM, Andrew wrote: >>>> Hi >>>> >>>> As part of my forensics psych course, we have been introduced to >>>> Guttman's smallest space analysis (SSA). I want to explore this >>>> approach >>>> using R, but despite finding some queries on the web about this same >>>> thing, have yet to find any answers. The MASS package doesn't seem >>>> to do >>>> the job, and the only thing I have been able to find is some >>>> proprietary >>>> software HUDAP? (Hebrew University Data Analysis Package) which >>>> may/ not >>>> be compatible with R (or GNU/Linux for that matter). >>>> >>>> Does anyone have information on how to do SSA using R? >>>> >>>> Many thanks >>>> >>>> Andrew >>>> >>>> >>>> ????[[alternative HTML version deleted]] >>>> >>> >>> >> > >