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0answers
15 views

Types of growth curves that can be compared using statmod compareGrowthCurves

I'm using the function compareGrowthCurves in the R package statmod, but I can't seem to find an explanation of what types of curve this is valid for. Does anyone ...
1
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0answers
58 views

Integrate first derivation - area under curve of first derivation

I want to calculate the area under the first derivate. Can I do that with splinefun()? ...
1
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1answer
33 views

Gaussian Process for Closed Curves

A Gaussian process gives a probability distribution over functions that pass through the data points. Is there a way to parameterize the Gaussian process to give a probability distribution over closed ...
1
vote
1answer
202 views

What is Precision-Recall Curve?

I have a data mining assignment where I make a content-based image retrieval system. I have 20 images of 5 animals. So in total 100 images. My system returns the 10 most relevant images to an input ...
2
votes
0answers
469 views

Test for statistical difference between two curves on same plot?

I've got data plotted for A/Ci curves (plant physiology, A=photosynthesis rate, Ci=internal CO2 concentration--essentially it's a dose-response relationship). Generally, when this type of data is ...
1
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0answers
27 views

Line smoothness/waviness

I am working on a project which requires me to watch video of athletes and measure the straightness/smoothness/waviness, whatever term is acceptable, of their spine. Dividing the spine into segments ...
2
votes
0answers
132 views

Comparing facial curvature of two human faces

I need help determining if what I'm doing is sufficient. I have extracted the "curvature" from two human faces (essentially the curve that goes from one ear, down the face to the chin, and back up to ...
2
votes
2answers
79 views

Estimation and comparison of flowering curves

I am a research scholar and monitoring phenological events of timber line at Himalayan region from past 4 years. During data analysis I found a research paper Estimation and comparison of flowering ...
0
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0answers
65 views

Frechet Mean of Multiple Curves

I'm working on determining the Frechet mean of several curves. I am using this equation: $$ \sum_{n=1} (P_a - P_b)^2 $$ but I'm not entirely sure how I would do this across multiple curves. Also, ...
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1answer
95 views

Unsupervised classification of curves (in R)

I'd like to know if there is a method (in R) to classify curves based mainly on their appearance ie one cluster will represent a specific form of curves. Thanks
1
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0answers
39 views

Hilbert curves: bounds / probabilities of preserving neighbors

Hilbert Curves (Wikipedia) are space-filling curves said to "fairly well preserve locality". Do you know any theoretical results here, such as bounds that neighbors within a radius of $\varepsilon$ ...
0
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0answers
41 views

Matching curves

I've a large number of curves over a finite interval. Given a new curve C, I want to find a set of curves in the database s.t the area between a matched curve and C is less than a certain threshold. ...
14
votes
2answers
517 views

Checking for a statistically significant peak

I have a set of data, $y$ and $x$. I would like to test the following hypothesis: There is a peak in $y$; that is as $x$ increases, $y$ first increases and then decreases. My first idea was fitting ...
2
votes
3answers
149 views

Are there methods for automatically detecting features of a curve?

I have a raw discrete data(curves). I need to find methods for detecting features of each curve. Some example features: 1) Stable growing 2) Fast growing 3) Stable falling 4) Fast falling 5) And so ...
9
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5answers
5k views

Similarity measures between curves?

I would like to compute the measure of similarity between two ordered sets of points---the ones under User compared with the ones under Teacher: The points are curves in 3D space, but I was ...
5
votes
1answer
375 views

Shape detection for time series data

I have a large collection of time series - measurements taken every 15 minutes (96 measurements in a day) over the span of 1 year at various different locations. I've broken up each time series into ...
2
votes
2answers
272 views

Convex vs. concave curve - measurement or index

I am interested in a measurement or index that will tell me if a curve is more convex or concave versus a straight line. This curve is sampled in n points and I know the x and y coordinates of these ...
0
votes
1answer
2k views

Tutorials for drawing an ROC curve

Are there tutorials you recommend that teach how to draw an ROC curve? Thanks.
5
votes
2answers
2k views

Fit between two curves

I am trying to determine the fit between two curves (example shown below). Both curves are plotted here as a bunch of XY data points (not functions). The curves represent the trajectories of two ...