Skip to main content

list manipulation - Turning table into association for Classify


I have the following sample data for 20 users. I know their sex, and the response for three yes/no questions. I am trying to building a classifier to guess their response to the third question, based on their sex, and the response to the first two questions. It is probably obvious but this is all made up data.


Here is the data:


{{{"M", "Y", "N"} -> "Y"}, {{"F", "Y", "N"} -> 
"N"}, {{"F", "N", "Y"} -> "Y"}, {{"M", "Y", "Y"} ->
"Y"}, {{"M", "Y", "Y"} -> "Y"}, {{"M", "N", "Y"} ->

"Y"}, {{"M", "Y", "Y"} -> "Y"}, {{"M", "N", "Y"} ->
"Y"}, {{"M", "Y", "N"} -> "Y"}, {{"F", "Y", "Y"} ->
"N"}, {{"F", "Y", "Y"} -> "N"}, {{"M", "Y", "N"} ->
"Y"}, {{"F", "Y", "N"} -> "N"}, {{"F", "Y", "N"} ->
"N"}, {{"M", "Y", "N"} -> "Y"}, {{"M", "Y", "N"} ->
"Y"}, {{"M", "Y", "Y"} -> "Y"}, {{"F", "Y", "Y"} ->
"N"}, {{"F", "N", "Y"} -> "N"}}

Then I make a training set from the first 10 elements of the data.


training = data[[1 ;; 10]]


and finally I try to use Classify using built in defaults


cf = Classify[training]

Which gives:


Argument {{{M,Y,N}->Y},{{F,Y,N}->N},{{F,N,Y}->Y},<<4>>,{{M,N,Y}->Y},{{M,Y,N}->Y},{{F,Y,Y}->N}} should be a rule, a list of rules, or an association. >>

I went through Iris data as practice, but since they uses built-in dataset, I'm not sure how the Associations were build behind the scenes.


I would like to understand:


1) How to convert my table, into associations? \ 2) In general, for Classifying is it better to use Mathematica's new Dataset structure?



This question does seems related to : Transform Dataset so it can be used as training set for Classify



Answer



You must change your list structure. right now it is in the form of a list of lists of associations. If you remove the lists, you will have a list of associations, which the classifier function can work with.


cf = Classify[Flatten[training,1]]

I would look at the documentation for AssociationMap and AssociationThread, for good examples of how to build associations.


Comments

Popular posts from this blog

plotting - Filling between two spheres in SphericalPlot3D

Manipulate[ SphericalPlot3D[{1, 2 - n}, {θ, 0, Pi}, {ϕ, 0, 1.5 Pi}, Mesh -> None, PlotPoints -> 15, PlotRange -> {-2.2, 2.2}], {n, 0, 1}] I cant' seem to be able to make a filling between two spheres. I've already tried the obvious Filling -> {1 -> {2}} but Mathematica doesn't seem to like that option. Is there any easy way around this or ... Answer There is no built-in filling in SphericalPlot3D . One option is to use ParametricPlot3D to draw the surfaces between the two shells: Manipulate[ Show[SphericalPlot3D[{1, 2 - n}, {θ, 0, Pi}, {ϕ, 0, 1.5 Pi}, PlotPoints -> 15, PlotRange -> {-2.2, 2.2}], ParametricPlot3D[{ r {Sin[t] Cos[1.5 Pi], Sin[t] Sin[1.5 Pi], Cos[t]}, r {Sin[t] Cos[0 Pi], Sin[t] Sin[0 Pi], Cos[t]}}, {r, 1, 2 - n}, {t, 0, Pi}, PlotStyle -> Yellow, Mesh -> {2, 15}]], {n, 0, 1}]

plotting - Plot 4D data with color as 4th dimension

I have a list of 4D data (x position, y position, amplitude, wavelength). I want to plot x, y, and amplitude on a 3D plot and have the color of the points correspond to the wavelength. I have seen many examples using functions to define color but my wavelength cannot be expressed by an analytic function. Is there a simple way to do this? Answer Here a another possible way to visualize 4D data: data = Flatten[Table[{x, y, x^2 + y^2, Sin[x - y]}, {x, -Pi, Pi,Pi/10}, {y,-Pi,Pi, Pi/10}], 1]; You can use the function Point along with VertexColors . Now the points are places using the first three elements and the color is determined by the fourth. In this case I used Hue, but you can use whatever you prefer. Graphics3D[ Point[data[[All, 1 ;; 3]], VertexColors -> Hue /@ data[[All, 4]]], Axes -> True, BoxRatios -> {1, 1, 1/GoldenRatio}]

plotting - Mathematica: 3D plot based on combined 2D graphs

I have several sigmoidal fits to 3 different datasets, with mean fit predictions plus the 95% confidence limits (not symmetrical around the mean) and the actual data. I would now like to show these different 2D plots projected in 3D as in but then using proper perspective. In the link here they give some solutions to combine the plots using isometric perspective, but I would like to use proper 3 point perspective. Any thoughts? Also any way to show the mean points per time point for each series plus or minus the standard error on the mean would be cool too, either using points+vertical bars, or using spheres plus tubes. Below are some test data and the fit function I am using. Note that I am working on a logit(proportion) scale and that the final vertical scale is Log10(percentage). (* some test data *) data = Table[Null, {i, 4}]; data[[1]] = {{1, -5.8}, {2, -5.4}, {3, -0.8}, {4, -0.2}, {5, 4.6}, {1, -6.4}, {2, -5.6}, {3, -0.7}, {4, 0.04}, {5, 1.0}, {1, -6.8}, {2, -4.7}, {3, -1.