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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-3
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0answers
14 views

Hard Interpreting Charts Problem [on hold]

https://drive.google.com/file/d/0B-4lJHUDH1P5bVNiTlpBbUhyRVk/edit?usp=sharing Here's the link for the problem
0
votes
1answer
12 views

Chart Question and Percentages

https://drive.google.com/file/d/0B-4lJHUDH1P5LVdaQVZEb1dZMlE/edit?usp=sharing Here's the link for the question The Venn Diagram above represents the 20 students who took one or more of the 3 ...
1
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2answers
18 views

How to interpret the result of correlation between two discrete signals

Before starting, let me say I'm not a mathematician, I'm just a curious engineer, with a master's degree in engineering and computer science. I have been using this book The Scientist and Engineer's ...
0
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0answers
11 views

Does logged data have to be transformed back to its original form before testing the accuracy?

I have run my data through a model in r, i ran ARIMA to forecast. The model forces a log transformation to be applied to the data. To test the accuracy of the fitted model formed by ARIMA would i need ...
0
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0answers
10 views

Making a graph with information

I would like to ask what appropriate graph I should use and maybe an example to help me, I am struggling on what type of graph will be appropriate for this, and knowing could help me with the further ...
-1
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1answer
22 views

SCATTER PLOT: Comparing two different datasets [closed]

I have two different fits files with different shapes (i.e. (310, 256, 256) & (560, 4, 786432)). How do i make two scatter plots to compare them using python? That's plotting one data on the ...
0
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0answers
18 views

Generalised chi square PDF: 2 normal DOF with different widths

I'm trying to derive the PDF $f_Z(x)$ for the random variable $Z = X^2 + Y^2$ where $X \sim N(0, \sigma_1)$ and $Y \sim N(0, \sigma_2)$. Searching here I've found this solution, which is only valid if ...
1
vote
1answer
27 views

Least squares fitting using cosine function?

Hello I am trying to fit a harmonic of the form $$y = b + c\cos(x)$$ to four data points (0,6.1) (.5,5.4) (1,3.9) (1.5,1.6) using least squares for homework. I know that the error $= Y_i - f(x_i)$ but ...
-4
votes
0answers
26 views

How to calculate the blanks with little data?

I am not a math man, however I am an IT student. I have tried for some hours with excel. Using the power function but i cant figure it out how to calculate this. I am not sure if it is even possible. ...
1
vote
1answer
13 views

What statistical analysis to use on a list of dates?

I suffer from migraines and for many years I've kept a log of each attack. I now want to do some analysis on the dates of each attack to see if there are any patterns. I intend to check the ...
3
votes
1answer
50 views

Queue and Stack in Computer Science and relation to MATH

For Creating a Queue Q we use two Stack S1,S2. for insert x in the end of Q we do Push(S1,x). for deleting element from front of Q, (if Q is not empty) we do Pop(S2). if on Q that at first is empty, ...
0
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0answers
38 views

Using significant figures, what would the answer be?

I've been learning about significant figures and I have a few questions. When you multiply/divide, the number of significant figures in the answer should be the same as the term with the least number ...
0
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0answers
11 views

Polynomial Data Fitting with Two Variables

I have the following data and I want to find the equation interpolating the given data. For example equation for given sample data is simple $a^2*b+10$ ...
5
votes
0answers
43 views

Careers in applied math with an MS other than in finance and data/machine learning?

Since I like math, I would like a career that uses alot of applied math. I'm about to complete my Master's and could do my thesis in numerical solutions of PDEs I'm already aware of careers such as ...
0
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0answers
33 views

How to find a graph's equation from its points

I have a set of data that constitutes the graph on the picture. What I want to know is how would I find the equation equivalent to that kind of graph? The X are on the interval $[1,10]$.
1
vote
1answer
40 views

Similarity measurement for strings of letters

Let's say, I have 10 different groups, and each group has its own string sequence. So, it should be like : G1 -> CHFAIEBD G2 -> HCFJIGBD G3 -> HCFAIJBD G4 -> HFCIJEBD G5 -> ..... G6 -> .... The ...
0
votes
1answer
15 views

Feature selection of Gabor filter

I am working with Gabor filter with level set method here. As you known, gabor filter gave many filter output. Some of them is not necessary. Could you suggest to me some method that can choose best ...
0
votes
3answers
24 views

fit sine wave to data

I have some astronomical data that I want to fit a sine wave to. I want to fit something of the form y = Asin(Ωt+Φ). I know the period of the sinusoid is equal to ...
1
vote
3answers
45 views

fit sine wave to data

I have some astronomical data which I know has a sinusoidal component to it of the form y = Asin(Ωt+Φ). The period of the sinusoid is equal to a sidereal day. So ...
1
vote
1answer
24 views

Find median given large amount of data

Listing all the possibilities would take time. Would there be a faster and more efficent way to find the median?
0
votes
0answers
12 views

Reading Graphs to solve probability

Each point in the scatterplot above represents a person's systolic and diastolic blood presures. What fraction of the 24 people had either a systolic pressure over 140millimeters of mercury (mm Hg) ...
0
votes
0answers
16 views

Normalizing Data for Graph

Firstly, sorry for the long post, but I must be detailed in my explanation here. This is a computer science heavy topic, and I've posted it on the CS section of Stack Overflow already, but the main ...
0
votes
1answer
38 views

How do you call it when you remove the top n% and the bottom n% of a dataset?

I am currently writing about a dataset of collected handwritings. I want to show some characteristics of the dataset. For example I think it is interesting to show how long it took users to create the ...
0
votes
2answers
38 views

Creating a polynomial function with no x-intercept

I have an understanding of polynomials and how to create a function based on the leading coefficient, degrees, x-intercepts, etc. My question is how do i go about creating a polynomial function that ...
1
vote
0answers
45 views

$y=\sqrt x \rightarrow \ln y = \ln x$ problem

So I had some raw data, and it looked like there was a square root relation. I plotted graphs of $y=\sqrt{x}$ They look kind of straight. So doing the algebra and taking the ln of both sides, we ...
1
vote
2answers
30 views

Finding similarity between elements using statistics

I have a dataset of DJs in which I'm trying to find DJs similar to a specific DJ. Each DJ has a set of a genres with a certain percentage. How can I find the similarity between 2 DJs? The following is ...
0
votes
1answer
25 views

Median value resulting in negative number

I know the that the formula for finding the median of grouped data that is: $$\mathrm{Median} = L_m + \left [ \frac { \frac{n}{2} - F_{m-1} }{f_m} \right ] \times c$$ And I also know what the ...
0
votes
1answer
22 views

Data interpretation problem

Approximately what is the minimum amount of caffeine, in milligrams, consumed per day by a person who daily drinks two 10-ounce mugs of percolated coffee and one 12-ounce cup of a caffeinated ...
0
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0answers
20 views

Low pass filter to maintain edge information

I am looking for a kernel as low pass filter that satisfy as:I must find a kernel that statisfies as follows: In the my reference paper, the author suggest gaussian kernel that is The gaussian ...
1
vote
1answer
24 views

Multidimensional fitting of two data sets

My problem is the following: A laser gives out a bunch of data points which are reflected off a metal surface and recorded by a camera attached to the side of the laser. The image the camera receives ...
0
votes
1answer
27 views

Finding a population Function

I have been given the population of the USA from 1790 - 1980 (increasing in intervals of 10) and I am asked to solve this differential equation. Using t as time in yearrs P as size of population at ...
0
votes
0answers
21 views

Estimation of real estate

I'm working on a project on estimating the price value of real estate. First I have collected a lot of data (500 000 instances) with details such as postal code, number of bedrooms, build year, ...
0
votes
1answer
37 views

Formula to link two exponential values together - doesn't quite work

Basically, I've done a script, and I'm stuck on a formula for it. After I run the code on a cube, based on two different inputs (detail level and vertex average iterations), the resulting size will be ...
0
votes
1answer
19 views

Work out if the relationship between 2 datasets is constant

I have 2 one-dimensional datasets, let's call them a and b. I want to know the correlation between ...
0
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0answers
37 views

How do you use R to find the box counting dimension of a two dimensional set of data, or scatter plot?

I'm using the software R to do some analysis on some data sets for a graduate project. R has a package called "fractaldim", in this package is a function for finding the box counting dimension. The ...
0
votes
1answer
21 views

Is there a way to use the Generalized Mean to find the “best” possible mean to use for a specific data set?

I've recently learned about the Generalized Mean as an abstraction of the many different means, includeing the Geometric, Arithmetic, and Harmonic means, as well as others. It is my understanding ...
1
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1answer
25 views

Survival analysis in survey dropouts?

I am working with a survey data set and am curious about who abandoned it before finishing all the questions. I have information on how many questions each respondent answered (no skipping allowed) ...
1
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0answers
37 views

Form of a function I can fit like a polynomial that has an asymptote on x-axis and is always positive

So I have a small list of pairs of the form $(\mathbb{R}, \mathbb{R}_{\geq 0})$ and I want to fit a function to this data. Additionally I know that as $x$ grows large in either direction $y$ tends to ...
0
votes
1answer
56 views

What is purpose of correlation kernel? IIs it high pass filter or low pass filter?

I am research about correlation kernel and I have some questions that need your help. Let see the pp. 3302-3303 in the http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=6517250&tag=1 The special ...
1
vote
0answers
36 views

Linear model for data that follow gaussian distribution

I have a question about linear regression. We have the linear regression of input data $(X,Y)=((x_1,y_1),(x_2,y_2)...(x_n,y_n))$ is $$F=aX+b$$ a,b are factors of the linear line, $y_i$ is {-1,1}. ...
0
votes
1answer
155 views

Finding the range from standard deviation and Gaussian Curve

The figure above shows a normal distribution with mean m and standard deviation d, including approximate percents of the distribution corresponding to the six regions shown. Suppose the heights of a ...
0
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0answers
22 views

What is correlation kernel and compare with gaussian kernel

I read a paper that said about correlation kernel that defined: $$W(x-y)=(α/1+d(|y − x|))$$ where $α =  (\int(1+d(y − x)dy)^{-1}$, $(d(|y − x|))$ is spatial Euclidean distance from the central ...
0
votes
0answers
19 views

Get a set of points from Fourier plot on Matlab?

I have a program that collects raw data and also does a Fourier transform to get complex numbers. When I feed the raw data into Matlab to do its own FFT, I can get a nice plot of power on frequency. ...
0
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0answers
8 views

Is there any common formula to estimate the salience of peaks of a histogram?

I need to use some quantitative measure to estimate the salience of peaks and the flatness of valleys of a histogram which represents the distribution of lightness of an image. For example, if an ...
0
votes
0answers
11 views

One-class Support Vector Machine Sensitivity Drops when the number of training sample increase

I am using One-Class SVM for outlier detections. It appears that as the number of training samples increases, the sensitivity TP/(TP+FN) of One-Class SVM detection result drops, and classification ...
1
vote
1answer
18 views

How to determine who improved the most considering diminishing returns

My friends and I are competing in a fitness challenge against each other. We will determine the winner based on who has the greatest percentage improvement after three months. Here is the problem: if ...
0
votes
1answer
31 views

Method for detecting anomalies in timeseries?

I am exploring creating alerts for anomalies in a timeseries. Say that I have a graph like this: There are two anomalies here that I would wanted to be alerted on: First, on April 7th with there ...
0
votes
0answers
44 views

How to interpret the indicator function?

I am reviewing a paper titled " Bayesian Sampling Approach to Decision Fusion" by Biao Chen and Pramod K Varshney. This paper uses an indicator function that I am not being able understand. The ...
0
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0answers
35 views

What type of equation matches these data points?

Can anyone tell me what equation will match these data points? 377, 384, 1113, 1120, 19861, 19868 Wolfram Plot
0
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0answers
36 views

Betfair Odds Percentage Movements & Hedging

I want to determine if the odds on Betfair have decreased by a certain percentage and then calculate the hedged profit when hedging on that percentage, but it's made tricky by the fact that decimal ...