Questions tagged [normalization]

Usually "normalization" means re-expressing data to make values lie within a specified range.

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1answer
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Length normalization in a naive Bayes classifier for documents

I'm trying to implement a naive Bayes classifier to classify documents that are essentially sets (as opposed to bags) of features, i.e. each feature contains a set of unique features, each of which ...
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0answers
3k views

Median adjusted normalization used in quantitative proteomics

Cross-posted from Biostar I'm stuck in a step for calculating Normalized intensity ratio for i-TRAQ reporter ions, used in quantitative proteomics. Here's the worked out example of how it's ...
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0answers
507 views

How to combine unbound variables with very different frequency distributions?

I want to combine three unbound variables. Each variable is the score provided by three different algorithms. Each algorithm predicts the likelihood (score) that a specific interaction between two ...
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4answers
22k views

What are the primary differences between z-scores and t-scores, and are they both considered standard scores?

We are currently converting student test scores in this manner : ( ScaledScore - ScaledScore Mean ) / StdDeviation ) * 15 + 100 I was referring to this ...
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1answer
4k views

How to do 'normalization'?

How do you do normalization so that when I get the mean/variance, the flat values wont affect the results? For example, in the figure below, Graph 1 & 2 are both considered to be noisy as compared ...
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0answers
488 views

Should we normalize the dataset before fitting the Gumbel distribution?

I tried to test if I should normalize the dataset before doing distribution fitting. ...
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4answers
22k views

“Normalizing” variables for SVD / PCA

Suppose we have $N$ measurable variables, $(a_1, a_2, \ldots, a_N)$, we do a number $M > N$ of measurements, and then wish to perform singular value decomposition on the results to find the axes of ...
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1answer
744 views

How to equalize the weight of each item in multiple checklists?

I have 5 checklists with different perfect scores. Say, I have checklist A-E with their corresponding perfect scores: A = 24 B = 17 C = 38 D = 41 E = 25 Each item in all the checklists are ...
16
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1answer
13k views

How does quantile normalization work?

In gene expression studies using microarrays, intensity data has to be normalized so that intensities can be compared between individuals, between genes. Conceptually, and algorithmically, how does "...
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5answers
251k views

What's the difference between Normalization and Standardization?

At work we were discussing this as my boss has never heard of normalization. In Linear Algebra, Normalization seems to refer to the dividing of a vector by its length. And in statistics, ...
2
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1answer
628 views

Accounting for biases in the data (normalizing? detrending?)

What's it called when I'm trying to remove the effect of a variable on another variable? Am I in the right ballpark using the terms "detrending" or "normalizing" or "controlling for Y on X"? What's ...
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1answer
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How to normalize data to let each feature lie between [-1,1]? [duplicate]

I have samples with each sample has n features, how to normalize these features to let feature values lie between interval [-1,1], please give a formula.
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0answers
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The boundary proprerty of conjugate exponential family

Consider a conjugate prior in the k-parameter canonical exponential family: $$p(w|n_0,y_0)=c(n_0,y_0) \exp(n_0(y_0 w'-b(w))) \, ,$$ where $n_0>0, y_0 \in Y$ is the pseudo observation vector, and $...
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1answer
371 views

How to construct quadrats for point processes that differ greatly in frequency?

I want to perform quadrat count analysis on several point processes (or one marked point process), to then apply some dimensionality reduction techniques. The marks are not identically distributed, i....
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3answers
52k views

Column-wise matrix normalization in R [closed]

I would like to perform column-wise normalization of a matrix in R. Given a matrix m, I want to normalize each column by dividing each element by the sum of the ...
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0answers
133 views

How can I rediscretize my data?

Related to my previous question, I have a dataset of 2D points with an associated label (this label can take 6 different values). As suggested in the answers to my other question, this can be modeled ...
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0answers
6k views

Normalizing data between 0 and 1

I am a novice when it comes to stats, so I apologize beforehand for the simplicity of my question. I trying to figure out the best way to normalize (this may be the wrong term) my data in so that the ...
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8answers
108k views

Data normalization and standardization in neural networks

I am trying to predict the outcome of a complex system using neural networks (ANN's). The outcome (dependent) values range between 0 and 10,000. The different input variables have different ranges. ...
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1answer
74 views

Is there a name for the “kernel principle”?

In many cases, we do not actually have to explicitly compute the normalization constant of a certain distribution, if we know its kernel and it corresponds to a known family. Is there a name for this ...
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0answers
175 views

What should I do to compare different sets of data?

I am a beginner in statistics, and I want to learn machine learning :). Therefore, I have gathered some sample data to practice. But, the problem is I want to create a feature (or attribute), which is ...
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3answers
2k views

Normalizing rating in a group of people [finding effectiveness]

I'm a new guy here. Hopefully, I'm asking this question to right forum. Problem: We have data of a group of people (P1, P2, P3). They rank their expertise (1-10, where higher number is better) in a ...
5
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1answer
2k views

Normalizing or detrending groups of samples

How do I detrend or normalize multiple series of data so that I can inter-compare between the series? Specifics below may not be appropriate for this forum. Please let me know and I can remove or re-...
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4answers
463 views

What is the name of this normalization (which yields mean 0 and sd 1)?

Is there a specific name for normalizing some data so that it has mean=0 and sd=1? Or do I just say "data was normalized to have mean=0 and sd=1"?
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3answers
161 views

Correcting experiment results

We have performed a microarray screening of about 200 samples. In each sample we measure about 100 different variables. For technical reasons the screening of these 200 samples was divided into two ...
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9answers
41k views

How to represent an unbounded variable as number between 0 and 1

I want to represent a variable as a number between 0 and 1. The variable is a non-negative integer with no inherent bound. I map 0 to 0 but what can I map to 1 or numbers between 0 and 1? I could use ...

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