Questions on the use of mathematical techniques to extract properties from given data. Consider if your question might be more suited for Cross Validated (stats.SE) instead.

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1answer
13 views

bias-variance trade off

Perhaps the most primitive (and yet very effective) way of estimating a density is by using a histogram. In a histogram, we can manage the 'precision' of the distribution by adjusting the number of ...
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1answer
38 views

How to find the function which models a set of data [on hold]

Given these coordinates: 1. (1, 4) 2. (2, 22) 3. (3, 85) 4. (4, 190) 5. (5, 370) 6. (6, 650) 7. (7, 1000) 8. (8, 1500) I know how to use a calculator to find ...
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0answers
7 views

Translating data query into Domain Relational Calculus

Given a following table named BOOKING, which contains three columns, guest_name, room_number and booking_date, how do I find the all the guest_name that have the same room_number and booking_date? I ...
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0answers
20 views

What function should I use to fit this data? Logistic function is not good enough fit.

I'm using curve_fit from numpy to try an fit some data I have. The function I used was the logistic function defined http://en.wikipedia.org/wiki/Logistic_function and the parameters I picked were ...
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0answers
13 views

Determine the multi-dimensional relationship given the data

I have a dependent variable - A and 3 independent variables, H,V and N I have a data for all the variables and dependency relationship is based on my operational knowledge. I'd like to know what ...
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1answer
20 views

Application of wavelet analysis in computer science

I am doing research in computer science (data mining), do you think wavelet analysis is useful for me?
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0answers
6 views

creating polynomials using sets of data to represent a correlation [migrated]

I need some guidance in creating a polynomial function that represents sets of data and its correlation, if that makes any sense. I know there Lagrange interpolation, least squares etc. I don't know ...
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0answers
19 views

How can I get the covariance just given the variance?

This is a fairly straight forward problem but I don't know how to calculate the covariance given just the variance of X and Y. Suppose X and Y are independent random variables such that Var(X)=1 and ...
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0answers
21 views

How to minimize the Kolmogorov-Smirnov statistic with Power-law distribution

I'm fitting data into a power-law distribution. In order to do this I need to solve two parameters: the scaling parameter $\alpha$ and the lower bound $x_{\min}$ In order for me to solve $\alpha $ I ...
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0answers
20 views

What is the related function between these point?

What is the related function between these point? $(1,5)(2,7.5)(3,8.75)(4,9.375)(5,9.688)(6,9.844)$ $y=ab^x$ does not relate?
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votes
1answer
36 views

Linear Regression Application

I have a linear equation as follows: $B_0*x_0 + B_1*x_1 + ... + B_8*x_8 = result$ And i have about 200 different situations that are categorized into two different groups, depending on whether ...
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0answers
28 views

Noise Reduction

I'm working on a problem that involves production rate data from oil wells. These rates are recorded per month i.e. after a month of production the produced volume is calculated and reported as rate ...
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4answers
43 views

Why do graphs sometimes have unevenly spaced intervals in axis e.g. logarithmic

Why do some graphs not have evenly spaced out units on the x or y-axis? For example they have log on one or both of the axis? Here's an example from this page I guess the page does give a bit of an ...
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0answers
28 views

Is Principal Component Analysis applicable to this type of situation?

I'm trying to model the response of ant populations to pheromones in this way: The ants are simulated as Self Propelled Particles with internal energy. They undergo acceleration due to their internal ...
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0answers
15 views

Significant difference in a group of numbers

I have a series of results for groups of students achieving a certain level and I need to highlight where the results for different groups are significantly high or low. For example: Results show ...
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0answers
23 views

Method for measuring co-occurence

I have a dataset that lists a large number of binary variables for each member of the populations. It basically looks like this: ...
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0answers
27 views

Predictive models

Given a set of temperatures of different cities for a month, which prediction model should I use for a two day look ahead prediction? Regression models or Time series?
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1answer
18 views

rotating and exchanging x for y's in regression

I was just wondering what happens generally if i send all my x points to y's and y's to x's (i.e reflect along the y=x line) - if I change the x's and y's will my old error minimizing line still be ...
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0answers
18 views

Compress Unit ID Permutations

For my multiplayer RTS game, I need to send over the ID's of a player's units selected in a single integer. For every player, there are 16 units, each with an integer ID between 1-16 (inclusive), and ...
1
vote
1answer
14 views

$P(X > \mu + \sigma) > 0$?

I'm doing some data analysis. Let $X$ follow an unknown distribution, with a certain average $E[X]$ and a standard deviation $\sigma$. Both values are calculated using the (corrected) point ...
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2answers
36 views

How do I find the missing sample points with the Mean and Sample Standard Deviation?

I am completely lost on this statistics question: A statistician had a data set containing 13 data points written in his research notebook. He spilled coffee on his notebook and now he cannot read ...
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0answers
37 views

Searching a function for data

I have a dataset and I am trying to find the appropriate function to fit them. So far, I have fitted the data into a two variable polynomial: $$ y(t,v)=(-525.958 + 4.88502 t - 0.0149025 t^2 + ...
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0answers
9 views

Categorical Survey Heterogeneity Measure?

A survey asks the user to assign ten stick figures into four categories: strongly oppose, weakly oppose, weakly support, strongly support. The survey has been completed, so it is too late to redesign ...
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2answers
28 views

Power set of a set containing a set

I need some help understanding this concept a little better. I understand the general power sets, but only worked nice and easy examples where only the set consisted of only single elements like ...
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0answers
12 views

What is the proper name of a model that takes as input the output of another model?

Thanks in advance for the help. I am writing a paper and for the life of me can't remember the proper term for a model that works as follows. rawData -> model1 -> outputModel1 -> model2 -> ...
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0answers
44 views

Are there any programs like family echo that I can use to map mathematics?

Family echo is an online program that allows one to make a family tree, if nothing is clicked it shows most of the family tree as it is, but if one clicks a name one can see clearly all the ancestors ...
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1answer
38 views

There are 2 red, 3 pink, 4 orange, and 5 yellow jelly beans in the pocket. how many different ways can you choose at least one jelly bean?

Thanks a lot!There are 2 red, 3 pink, 4 orange, and 5 yellow jelly beans in the pocket. how many different ways can you choose at least one jelly bean?
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2answers
55 views

What property of $n$ does this test?

I have the following sample data: 1 true 3 false 12 false 10 true 7 true 9 false 8 false My question is, what property of ...
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0answers
23 views

How to normalize scoring to eliminate bias?

Background: I'm writing an app to allow multiple people to rate an object on a scale of 1-10. There are a few hundred objects to be rated, so I'd like to allow the reviewers to review what they can, ...
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1answer
19 views

Detecting periodic patterns in data - how often are the meetings held?

Suppose some people I know frequently have meetings, and suppose I want to find out whether there's a pattern to when these meetings take place, and if so how often they occur. I can take note of the ...
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0answers
32 views

What is the relationship between the Fourier spectrum and the information content?

Suppose you look at the Fourier transform of some data (say, a blurred image). The amount of high frequency signal tells you how much texture there is in the data (e.g., a blurrier image has a more ...
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0answers
53 views

How can non-binary data be tested for distinguishability from random?

Given a large string of Base-N digits (in other words, not necessarily binary), is there software or an algorithm that can output whether the data is reasonably pseudorandom or reveals a pattern? In ...
0
votes
1answer
20 views

comparing empirical data to a model prediction using exponents

I am not a mathematician, but I have a basic question about comparing numbers with exponents near $1$. I am evaluating how well a "model" works and I want to make a compelling case. For example, my ...
2
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1answer
35 views

Predicting the increase/decrease of number

I have these entries in my database that looks like this: ...
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0answers
7 views

Scale a distribution to a new range and average

I've seen some linear scaling examples, but they don't really do what I want. I have a range of numbers from 0% to 126%, with an average of 75%. I want to map those to a range of 0% to 200%, with an ...
2
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0answers
36 views

How can I infer order from partially ordered discrete sequences?

A really interesting problem that I can't stop thinking about! Have run in to this a couple of times but yet to find a smart approach to either solve or frame this problem. This is my try at ...
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0answers
13 views

SEnsitivity Indices are non zero

I am trying to compute the sensitivity indices (SI) of a function using Monte Carlo simulation. I had written a matlab code that perform the computation directly and just return the final answer of my ...
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0answers
16 views

Help with finding an optimal bilingual skill-based routing calculation.

First time post, I'm not sure if it is in the correct forum but this seems to be as a good place to try: I was wondering if anyone out there had experience dealing with a similar issue or knew of any ...
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0answers
14 views

Statistics linear modelling in R

Suppose I have a date set of the form: Test Subject/Sex/No. of mistakes made in the morning/ No. of mistakes made in the afternoon A / M / 2 / 5 B / F / 1 / 4 C / M / 3 / 5 D / F / 1 / 5 Suppose ...
1
vote
1answer
99 views

Unsupervised learning algorithms to detect anomaly in waves.

I have a sample of graphs (more than 10000...). that look like in the image below: I am searching for an unsupervised learning algorithms that can help me to detect anomalous observations. Here ...
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0answers
141 views

How does 2D kriging interpolation work?

I have a grid of points Example ...
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0answers
11 views

PCA: what if continous variables are frequencies

I've got a data set that exists out of 5000 variables and 6000 instances. Each element of the data sets describes a frequency. It's a documentTermMatrix. Now I would like to do some data reduction, ...
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0answers
9 views

Hurst exponent for decay evaluation

i would like to evaluate rate of decay of tail of my histogram. Expressing histogram on loglog plot gives straight line in the range where i have gathered a lot of data. Unfortunately the line is ...
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0answers
14 views

Curve 'anti-correlation' detection

If I have a data set, what algorithm can I use to detect when one curve moves in clear opposition to the majority of curves? For example: At point 15, the purple line moves up in opposition to the ...
2
votes
1answer
47 views

Entropy determination regarding lossless data compression

Suppose I had many computer data files to compress losslessly and wanted to know what is the theoretical limit to each one as far as minimum filesize possible. How would a math person go about doing ...
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0answers
44 views

Analyzing/Modeling DynamoDB Usage

I'm seeking the correct mathematical tools to analyze/model a real world process for the purpose of optimizing resource allocation. I want to analyze consumed throughput of a AWS DynamoDB table and ...
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0answers
36 views

solving T(n) = 4T(n/2) + n^3 + n*(log(n))^2

I am trying to solve a recurrence by using substitution method. The recurrence relation is: $$T(n) = 4T\left(\frac n2\right) + n^3 + n\cdot\log^2 n$$ i tried to solve this also with master method... ...
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0answers
29 views

Maximum Error Tolerances When Forecasting A Random Time Series

I have been working on an approach for forecasting random time series with a given maximum error tolerance for each forecasted point less than 10%-15% of the range of possible values. I have not been ...
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0answers
41 views

Mean value of discrete periodic signals

It is clear that a continuous periodic signal always takes at some point $x_m$ the absolute mean value. Then we could define the absolute mean value of the signal as the value that it takes at $x_m$. ...
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2answers
35 views

Finding simplest function to distinguish 2 sets

I wish to find a function that distinguishes $2$ sets. I have m data values in form of n-tuples out of which k are supposed to be mapped to a value less than $0$ and other m-k are supposed to be ...