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16 views

Is discretization still the only way to deal with continuous and count variables in data mining association algorithms?

I have recently read a book chapter of data quality in which the author is against turning continuous variables in groups. While I agree with some of his arguments, I was not be able to find a way to ...
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1answer
32 views

Is this a scale or ordinal variable

I have a questionnaire distributed to the users with the following question from which users can select an answer Q: What was the project Cost Performance Index ...
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0answers
15 views

NMDS for biomass

I would like to make a NMDS with biomass of different prey groups in stomach content of fish.. I have already made one where the data matrix consists of 0 and 1, and this one went fine but are not ...
0
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1answer
41 views

Statistical test to show association of any kind between two variables

I have two continuous variables which I have data from a physics exspirment. I want to test for association between the two variables but without assuming a monotonic relationship. I also only have 6 ...
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0answers
7 views

How to convert contineous variable to descrete in R? [migrated]

I have a variable which encodes group ID: d <- data.frame(group = c(0,1,0,2,1,3,2,0,1,2), x=c(1.2,2.3,3.2,2.1,1.3,1.5,2.3,0.4,1.3,1.7)) When I try to use it ...
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0answers
41 views

What is the Net Promoter Score Data Type

As many people know Net Promoter Score is a customer feedback measure calculated from the response to the question: "How likely would you be to recommend [us] to a friend or colleague". The response ...
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0answers
186 views

How to test correlation between an ordinal and a continuous variable?

Which is the best way to test correlation between what I think it is an ordinal variable (the no of weeks worked out of first 8.. which can take values from 0 to 8) and a continuous variable (the ...
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0answers
35 views

Non-normal data and non-parametric tests [duplicate]

I have two non-normal variables (one DV, one IV) and a few 7-point Likert scale IVs (normally distributed). The non-normal variables are centrality scores from network analysis - DV is from the ...
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0answers
91 views

Am I looking at count, ordinal, or continuous data? Using a self-report questionnaire of depression

I am using the PHQ-9, a measure of depression. Here is a link to it: http://www.waterloowellingtondiabetes.ca/usercontent/documents/PHQ9PatientHealthQuestionnaireforDepression.pdf I am wondering ...
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1answer
163 views
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0answers
45 views

High heteroscedasticity level

My dependent variable - logincome - and one independent variable - age - are continuous. All other explanatory variables are categorical including BA_degree, race, occupation, region, homeownership. ...
2
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1answer
109 views

Analogues of sensitivity and specificity for continuous outcomes

How can I calculate the sensitivity and specificity (or analogous measures) of a continuous diagnostic test in predicting a continuous outcome (e.g., blood pressure) without dichotomizing the outcome? ...
1
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1answer
579 views

ANOVA or Regression? 1 Continuous factor & 1 Categorical factor with continuous response variables

I have 1 categorical factor (3 treatments) and 1 continuous factor (weight) and then I have 5 continuous response variables. From what I have read, I should not use a two way ANOVA as one of the ...
2
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0answers
46 views

Static Bayesian networks using p-values

In your opinion, what is the best way of handling Bayesian networks using continuous data, in this particular case, p-values? I have read about several discretization techniques, Gaussian approaches, ...
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0answers
36 views

How to discretize training and test files to not encounter inconsistency in data?

I have a problem in discretizing my data. My data comprises of two parts: training data and test data. I discretized training data using some parameters of equal-width binning and used the same ...
1
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1answer
95 views

Significant regression for the dichotomised predictor variable and not the continuous version of a predictor variable?

I am interested in examining the association between cardiorespiratory fitness and PCA derived dietary pattern scores in 264 adolescents. My cardiorespiratory fitness predictor is vo2max, and my ...
2
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1answer
435 views

How to analyse a continuous response having a bimodal distribution?

I am investigating unconscious racial prejudice as a predictor for guilty or not guilty judgements (Using SPSS). I have a continuous variable for unconscious racial prejudice (higher numbers equal ...
2
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0answers
97 views

Inferring transition matrices in continuous time Markov processes

Suppose I have a process X1, for which I do not have a generator matrix, only a transition (probability) matrix P1 for some time interval T, e.g. T=100. Suppose I have another process X2, such that X2 ...
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0answers
82 views

How to count variables in Cox PH model?

I am doing Cox PHR and I have several categorical, ordinal and continuous variables. Now we did univariate analyses (Log-Rank test) categorizing each continuous variable into 2 categories (based on ...
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1answer
129 views

Comparing continuous predictors for a dichotomous variable

I have two continuous predictor variables to predict a dichotomous variable. In addition i have constructed two (interaction) models, based on domain knowledge which use both variables to predict the ...
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2answers
224 views

Computationally efficient estimation of multivariate mode

Short version: What's the most computationally efficient method of estimating the mode of a multidimensional data set, sampled from a continuous distribution? Long version: I've got a data set that I ...
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0answers
68 views

Dependent variable maximum value contingent on independent variable

I am trying to create a model for debt collections. In the past I have used logistic regression to predict pay/no-pay. This has worked well but has a few unfortunate consequences. People are more ...
4
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2answers
258 views

Probability of two values being equal in a sample drawn from a continuous distribution

I am reading about the Kolmogrov-Smirnov tests from the book Probability and Statistics by DeGroot and Schervish. In the initial few lines on this topic, the authors state the following:- Suppose ...
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1answer
200 views

How to perform linear regression with categorical factors? [duplicate]

Possible Duplicate: How to test the statistical significance for categorical variable in linear regression? I need to perform a multiple regression analysis. My dependent variable or ...
2
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1answer
76 views

Correspondence analysis on a table of means

I have a table of the following kind: Cat1 cat2 cat3 ... Var1 6.3 5.3 8.3 Var2 5.2 5.7 6.1 Var3 2.2 3.9 7.6 . . . It is a table of means for ...
1
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1answer
135 views

Rare Events Model with a discrete index as the dependent variable?

I'm looking for a rare events model where the dependent variable is a discrete index, which means I cannot use the rare events logit model (Gary King). My dependent variable is an index of integers ...
0
votes
1answer
63 views

machine learning to predict equations / parameters of equations

I'm not sure if machine learning is the best way to do this, but I'm interested in seeing if this problem is feasible. Normally you use machine learning for classification. ie.given the size of a ...
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3answers
487 views

Binary classification vs. continuous output with neural networks

Wikipedia says in binary classification: Tests whose results are of continuous values, such as most blood values, can artificially be made binary by defining a cutoff value, with test results ...
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0answers
92 views

Maximum-entropy joint pdf

I have multiple (finitely-many) variables with independent posterior pdfs $f_{x_1}...f_{x_n}$ based on Bayesian updating treating them as independent with independent evidence. If I subsequently ...
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3answers
781 views

Clustering a dataset with both discrete and continuous variables

I have a dataset X which has 10 dimensions, 4 of which are discrete values. In fact, those 4 discrete variables are ordinal, i.e. a higher value implies a higher/better semantic. 2 of these discrete ...
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1answer
1k views

Predicting with both continuous and categorical features

Some predictive modeling techniques are more designed for handling continuous predictors, while others are better for handling categorical or discrete variables. Of course there exist techniques to ...
4
votes
1answer
348 views

Probability that a quadratic equation with random coefficients has two real solutions?

In the following second order equation $ax^2+2bx+1.5=0$ where $a$ and $b$ are given by random points $(a,b)$ in the $[0,2]\times[0,1]$ rectangle, what is the probability of having two real solutions? ...
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2answers
2k views

Correlation between dichotomous and continuous variable

I am trying to find the correlation between a dichotomous and a continuous variable. From my ground work on this I found that I have to use independent t-test and the precondition for it is that the ...
5
votes
1answer
1k views

How to choose between ANOVA and ANCOVA in a designed experiment?

I am conducting an experiment which has the following: DV: Slice consumption (continuous or could be categorical) IV: Healthy message, unhealthy message, no message (control) (3 groups in which ...
3
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2answers
558 views

Comparing odds ratios of continuous and discrete variables

I need to compare the ability of two methods to predict an event with a binary response. Each method produces a score, where the higher score indicates 1 and a lower score indicates 0. I am looking to ...
5
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1answer
209 views

Incremental training of Neural Networks

Is it valid to train a neural network over and over again with new arriving data (including pruning after each new training)? I plan to collect data for a period of time, train/cv/test the networ, ...
1
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1answer
488 views

Interaction terms interpretation

How do you interpret an odds ratio of an interaction between two continuous variables $x_1, x_2$? Would you fix $x_2$ and let $x_1 = x$ and $x_1 = x+1$?
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0answers
196 views

Using controls as basis for quantile/tertile categorization

I have a number of continuous but really skewed variables in the statistical analyses I am currently performing. Even though I am strongly in favour of keeping them just as they are and relaxing ...
0
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1answer
189 views

Bayesian updating of continuous variables given mutual information

I have very little stats training, so this may be a very obvious and boring question, in which case I apologise. Given two real-valued continuous random variables A and B, and given prior probability ...
0
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1answer
631 views

How to visualize an interaction effect from a regression?

I have a regression with a harmonic effect of day of the year, which interacts with other variables. I am not sure how to interpret the coefficients. My model is: ...
0
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1answer
193 views

Discretize frequency of words that follow zipfian distribution

How could I discretize the frequency of words found in a corpus that follow a zipfian distribution? Are there standard methods? It should create bins of exponential-increasing size. My goal is to ...
2
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0answers
45 views

Calculating probability of discovery

I have a planner that can evaluate N arbitrary states, and calculate their fitness. The domains it evaluates have no explicit "end state", so it has an infinite horizon. What are good methods for ...
2
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1answer
304 views

Do the properties of Pearson's chi-squared test for independence hold true for continuous PDFs?

In probabilist statistics, the properties of a discrete Pearson's chi-squared test hold that: \begin{aligned} \chi^2 = \sum_{i=1}^{r} \sum_{j=1}^{c} {(O_{i,j} - E_{i,j})^2 \over E_{i,j}} ...
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2answers
212 views

Best practices when treating range data as continuous

I am looking at whether abundance is related to size. Size is (of course) continuous, however, abundance is recorded on a scale such that ...
1
vote
1answer
152 views

Continuous-states hidden Markov chain

How to deal with HMC that has continuous states? Any papers, links, materials that explain the solution?
1
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2answers
347 views

Can I use log-likelihood distance on data of only continuous variables?

I have to run a SPSS two-step cluster analysis. All my 4 variables are continuous scalar standardized parameters (with normal distribution). The dataset includes 10,000 cases. SPSS suggest to use ...
1
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1answer
222 views

NAs in summary of linear model generated from significant genes for continuous response variable identified using SAM

I have a gene expression data-set with log2-transformed expression values (no NAs) for 495 genes for 59 samples for which values of a continuous response variable (r) are also known (no NAs). I want ...
2
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0answers
64 views

Density related to sparseness measure

Are there any multi-variate continuous distributions whose probability distribution functions give high values for sparse vectors and low values for dense vectors, i. e. indicating the sparseness of ...
1
vote
1answer
277 views

Why are most standard goodness of fit tests based only on continuous distributions?

I tried to search info regarding this fact but I don't really understand why most of the standard goodness of fit tests (e.g. Kolmogorov-Smirnov, Anderson-Darling, a part of the Chi-square test, ...
1
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1answer
791 views

Can random effects apply only to categorical variables?

This questions might sound stupid, but... is it correct that random effects could apply only to categorical variables (like individual id, population id, ...), e.g. say $x_i$ is categorical variable: ...

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