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1answer
76 views

What does R do with negative values in log() scale?

Some context of the problem: I am working on an analysis of some hypothetical donation data: I would like to investigate the differences between 'major donors' (those whose largest single donation is ...
1
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2answers
56 views

Likert Scale 3 2 1 0 1 2 3 possible?

In my questionnaire I want to ask people to score on a dimensional Likert-type scale their attitude toward a specific target group. E.g. People with .... are stupid.... intelligent. I want to use ...
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0answers
19 views

Which type of feature scaling to use [duplicate]

I've been writing some simple machine learning algorithms and looking at time-series data. In doing so, I have come across the use of feature scaling: rescaling and standardizing as they are referred ...
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0answers
86 views

Scaling categorical data in regression

It seems odd to scale a categorical variable, but I need to get the correct coefficients for each of my variables in linear regression. Is it correct to scale the same way you would with continuous ...
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0answers
14 views

Mathematics of simple performance testing [duplicate]

I have a set of sorted tables T that have known but different dimensions. There are two types of functions in this system: f(T) g(T, n), where n is an integer parameter. ... and two types of costs ...
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0answers
102 views

Similarities and dissimilarities between optimal scaling procedures in CATPCA and MCA

I have seen that multiple correspondence analysis (MCA) can also be seen as a generalization of principal component analysis when the variables to be analyzed are categorical instead of quantitative. ...
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0answers
18 views

How to implement optimal scaling of categorical variables for fuzzy clustering?

I am referring this paper "Fuzzy e-Means Clustering of Mixed Databases Including Numerical and Nominal Variables" from IEEE for implementation and learning. Kindly correct my understanding so far: ...
0
votes
1answer
18 views

should weights be scaled too?

I am using supervised learning algorithms (specificly SVM) on my data. I know that scaling was needed for my input data. however as I am also adding weights (using pairwise comparison), I am not sure ...
1
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1answer
48 views

Scaling in SVM (why and how to , plus references)

Hi I know why feature scaling is preferred in SVM, I have two questions: 1-does anyone know of legit articles of books explaining it. I am writing my thesis and I need references. It doesnt have to be ...
1
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1answer
207 views

optimal scaling / CATREG for imputed data

I have a data set with 5 different kinds of nutrient statuses and I want to see whether they are associated with categorical / ordinal grades at school. I have multiple covariates which I will ...
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0answers
39 views

What is PRINCIPAL HESSAIN Direction Model, how and where can I use it?

I'm a M.Tech student going through my academic project-work, here I have asked to develop a optimal design and a best equation to fit the data for a Leaching, Solvent extraction and Electrowinning ...
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0answers
44 views

Question on scaling data

I have been reading Elements of Statistical Learning. And I saw some example R codes written online. I realise that very often the explanatory variables $X$ (the data of the predictors) are ...
1
vote
1answer
295 views

Can I categorize the factor scores to use them as predictors of an ordinal logistic regression?

I was wondering if I can categorize the factor saved scores by taking their quartiles (or some other measures, I am not sure what should I use!) as cut points and use them as predictors in an ordinal ...
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0answers
255 views

Optimal scaling level for variables categorized from continuous data

A variable was categorized into 10 equally spaced intervals from a continuous variable which was originally in proportion. Now, we have to use this variable in CATREG procedure. If we choose the ...
7
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0answers
230 views

Can I use optimally scaled variables for a factor analysis to account for rotation? If I can then how?

I have discussed this issue several times in this site, but I am asking it again for a final justification from the experts of our community. I wanted to extract four factors (I should call dimensions ...
2
votes
0answers
372 views

How to obtain optimally scaled data from homals in R?

I am using the homals-package in R to optimally quantify my data that contains categorical (nominal and ordinal) as well as numerical variables. My goal is to ...
5
votes
1answer
893 views

What is the advantage of transforming variables from nominal to ordinal/numerical when it reduces variance explained in CatPCA?

Context I have a dataset of 8 categorical variables. And I want to apply Categorical Principal Component Analysis (CatPCA). Before doing that, I have been advised to look at the transformation plots ...
5
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1answer
1k views

How to calculate Rousseeuw’s and Croux’ (1993) Qn scale estimator for large samples?

Let Qn = Cqn.{|Xi-Xj|;i < j}_(k) so for a very short sample like {1,3,6,2,7,5} it can be calculated from finding the kth static order of pairwise differences: 7 6 5 3 2 1 1 6 5 4 2 1 2 5 4 3 1 ...
4
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1answer
121 views

Parametric Surface Reconstruction from Contours with Quick Rescaling

I'm looking to construct a 3-D surface of a part of the brain based on 2-D contours from cross-sectional slices from multiple angles. Once I get this shape, I want to "fit" it to another set of ...
6
votes
1answer
674 views

How can I use optimal scaling to scale an ordinal categorical variable?

In an answer to this question about treating categorical data as continuous, optimal scaling was mentioned. How does this method work and how is it applied?