# Tagged Questions

28 views

### PCA on a heterogenous correlation matrix better than MCA?

I have a questionnaire of 80 questions that I need to do dimension reduction on. About half the questions are ordinal (Likert-style questions), and the other half are qualitative/nominal. I've been ...
16 views

### How to calculate user-category affinities, given user-item scores for categorized items?

I have 2 million (user, item, category, score) tuples, where users give 0/1 scores to items that belong to categories. I want to convert these to a set of (user, category, affinity) tuples, using the ...
76 views

### Correlation among categories of categorical nominal variables

I have a data set with two categorical nominal variables (both with 5 categories). I would like to know if (and how) I am able to identify potential correlations among categories within these ...
41 views

### Dependency of a third factor in a correlation between 2 continuous variables?

I'm studying the correlation between 2 continuous variables (A~B), the first is an independent measured variable (A), the second one is a dependent estimated variable (B). I'd like to know i) if the ...
148 views

### Correlation between vegetation and erosion

I am wanting to find the correlation between two variables: a categorical vegetation variable (with categories 1-4) and a continuous variable of erosion (with values anywhere between 0.2 and 9). I ...
72 views

### How do I study the correlation between two categorical variables?

Say I have 1000 unique websites in my sample. Each website has two categorical variables assigned to it: PolicyDomain (e.g. 0 = "health", 1 = "defence", etc... up to 42). Community (e.g. ...
460 views

### Correlation between scale and categorical variable

I am trying to find the correlation or association between a categorical variable - classes from 1 -4 from a GIS (geographic information system) classification - and a continuous variable with values ...
106 views

### Correlation or independence on contingency table for large N

I have a dataset with about 35,000 individuals described by around 15 categorical variables. I'm trying to study the independence / correlation between these 15 categorical variables. My first idea ...
127 views

### Correlation and categorical variables

I have a series of categorical variables I have, up until now, been undertaking correlation analysis with. The bulb has now lit up and I'm realising that I've used completely the wrong analysis if I ...
528 views

### How to compute the correlation coefficient between continuous and discrete variables ?

Is there any adjustment required when computing the correlation coefficient between: continuous and discrete variable two discrete variables ? Thanks !
45 views

### Need help selecting test for nominal IV with categorical DP

I am going to attempt to give you as much background as possible. My independent variable is nominal and describes the number of days after which an insect was exposed to new conditions (0,1,3,5,7). ...
79 views

### Attempting to investigate a relationship between one variable and another that has three possible values

I'm looking to investigate the relationship between a series of variables on a recurring basis. One variable will always be the dependent variable, and will take three possible values: ...
120 views

### Point-biserial correlation with unequal groups in dichotomous variable

The dichotomous variable I want to use for a point-biserial correlation has very unequal n's ($n_1=140$, $n_2=6$). Would this be breaking any rules? What would this mean for my results? Would it just ...
81 views

### Establishing relationship between discrete vector and categorical vector

I have a vector of positive integer counts taken from a time-series (365 observations/days). I believe that there is variance in these counts due to the day of week they are observed and as I am ...
734 views

I’m using Stata 12.0, and I’ve downloaded the polychoricpca command written by Stas Kolenikov, which I wanted to use with data that includes a mix of categorical ...
3k views

### About correlation of ordinal variables having different number of categories and about correlation of mixed type of variables

I have three questions: For data with different response categories (likert type or ordinal) what type of correlation should be calculated? I know for ordinal variables Spearman's rank correlation ...
308 views

### Regression with categorical factor variable and the correlation among the variables

lm(y~x1 + x2 -1) where x1 is a continuous numerical variable and x2 is a categorical ...
8k views

### How do I study the “correlation” between a continuous variable and a categorical variable?

What's a meaningful "correlation" measure to study the relation between the such two types of variables? In R, how to do it? Thanks a lot!
7k views

### How to measure correlation between categorical variable?

I know that we can use Spearman rho to measure the correlation between numerical variables. But how to measure correlation between categorical variables? Thanks
769 views

### How to perform correspondence analysis on ordinal data in SPSS?

I have 500 rows and three columns. Two of the variables (that i want to analyze) are in ordinal form and the other in scale. However, when i run the correspondence analysis wizard in SPSS i can only ...
10k views

### How to correlate ordinal and nominal variables in SPSS?

I have imported an Excel document in SPSS which contains around 500 entries. Three columns are defined using Likert scales. I have substituted textual values with numerical values from 0 to 4. The ...
636 views

### How to best analyze non-mutually-exclusive categorical outcome with categorical predictor and categorical blocking factors?

Here is an example: I have a set of observations of different individuals from lots of different families of grasses: ...