Linked Questions

0
votes
1answer
2k views

Hierarchical clustering with categorical variables - what distance/similarity to use in R? [duplicate]

I have only categorical variables in my database. What distance/similarity to use? I´m using the function simil() (library(proxy) in R.
41
votes
2answers
56k views

Choosing the right linkage method for hierarchical clustering

I am performing hierarchical clustering on data I've gathered and processed from the reddit data dump on Google BigQuery. My process is the following: Get the latest 1000 posts in /r/politics ...
39
votes
2answers
29k views

Hierarchical clustering with mixed type data - what distance/similarity to use?

In my dataset we have both continuous and naturally discrete variables. I want to know whether we can do hierarchical clustering using both type of variables. And if yes, what distance measure is ...
21
votes
4answers
7k views

With categorical data, can there be clusters without the variables being related?

When trying to explain cluster analyses, it is common for people to misunderstand the process as being related to whether the variables are correlated. One way to get people past that confusion is a ...
23
votes
2answers
24k views

Similarity Coefficients for binary data: Why choose Jaccard over Russell and Rao?

From Encyclopedia of Statistical Sciences I understand that given $p$ dichotomous (binary: 1=present; 0=absent) attributes (variables), we can form a contingency table for any two objects i and j of a ...
6
votes
3answers
5k views

Understanding $\chi^{2}$ and Cramér's $V$ results

I have two groups of buyers, A and B, and I want to test whether the difference between the percentage of them who would buy a ...
5
votes
1answer
26k views

Hierarchical or TwoStep cluster analysis for binary data?

(This question is an edited version of a question I previously posted which one user recommended would benefit from more focus). I have 2000 questionnaires from respondents which ask 33 different ...
9
votes
1answer
7k views

Was it as valid to perform k-means on a distance matrix as on data matrix (text mining data)?

(This post is a repost of a question I posted yesterday (now deleted), but I've tried to scale back volume of words and simplify what I'm asking) I'm hoping to get some help interpreting a kmeans ...
4
votes
2answers
8k views

Accuracy vs Jaccard for multiclass problem

TL;DR For a multiclass problem, is Jaccard score the same as accuracy? Update March 29, 2019 The wrong implementation in scikit-learn is now fixed with pull request #13151. Hooray! P.S. The lesson ...
4
votes
3answers
3k views

Distance metric for all categorical data

I have categorical data in the form of Y/N of 23 attributes and containing 200+ records. I need to compute the distance between the attributes with their class label. Which metric can be used?
4
votes
0answers
6k views

Properties of Levenshtein, N-Gram, cosine and Jaccard distance coefficients - in sentence matching

Let's say I have two strings: string A: 'I went to the cafeteria and bought a sandwich.' string B: 'I heard the cafeteria is serving roast-beef sandwiches today'. ...
3
votes
0answers
7k views

K-Means Clustering with Dummy Variables

I want to use k-means to cluster my data. I have broken one column into 4 dummy variables and I have normalized all of the data to mean=0 and sd=1. Will k-means work with these dummy variables? I ...
5
votes
1answer
1k views

How to distance and to MDS-plot objects according their complex shape

Suppose I have four basal forms of signal (blue, purple, red, green). I also have created transition forms between each other. If you carefully look on the picture below, you can see that for example ...
2
votes
1answer
2k views

NMDS from Jaccard and Bray-Curtis identical. Is that a bad thing?

The dataset is ecological (species abundance), where I am calculating distances between 51 sampling sites, based on abundances of 3200 species. The species abundance values go up to 2700, and the rest ...
4
votes
1answer
496 views

Using metric MDS with non-metric distances and assessing the fit quality

I'm going to perform MDS by means of cmdscale function of standard R library. I spent several hours googling it and finally have ...

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