Questions tagged [astronomy]
Astronomy (from Greek: ἀστρονομία) is a natural science that studies celestial objects and phenomena. It applies statistics and other mathematics, physics, and chemistry in an effort to explain the origin of those objects and phenomena and their evolution.
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Could classical astronomic discoveries be made using ML?
Imagine that prior to the time of Copernicus, scientists could run machine learning algorithms (somehow).
Would it be possible to discover the truth of the geocentric model with their use?
Would the ...
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Dataset with two unique trends?
I have a scatterplot displaying one data set that, at first glance, has a weak negative correlation. Upon further inspection, however, it appears that the data set shows two stronger linear trends ...
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Measure of goodness of polynomial fit at specific points or weighted analysis?
I have some astrophysics data of "particle density vs orbital position" of a moon that emits a lot of particles. My research deals with the intensity of the scattered light which is ...
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Converting a chi2 to a sigma value
I am working in astronomy. I fit a theoretical model to some data. The model takes input parameters (like the mass and age) and produces some outputs that I compare with the data.
I measured the ...
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Bayesian or Frequentist goodnes of fit: depends on the data?
I'm working with the data of the real masses of exoplanets published in the catalogues (NASA, exoplanet.eu). Those catalogues update almost everyday by adding new exoplanet data or correcting some of ...
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How to compare distributions with errors on the data points?
Here's a mock set-up of my problem:
I have two non-normal probability density distributions (PDFs), $A$ and $B$.
Distribution $A$ has error measurements for each data point while distribution $B$ ...
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Sampling from an infinite population
SAMPLE SIZE
I am sampling astronomical data and measuring clusters of galaxies (within a range of 100 megaprsecs) as nodes in a complex network, where k is a metric ...
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How to interpret this scatter plot?
I am simulating a population of binary stars by generating many samples of orbital parameters. I'm investigating the relationship between the inclination of the orbit and the fraction of the ...
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biplot of PCA data gives very unusual
Very much a new at data analytics, with some functional understanding of statistics. I was referred to this site from elsewhere.
I am looking at ca. 1000 optical spectra, data available from the ...
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Error Propagation through Iterated Functions (variable star data)
I'm an astronomer trying to smooth variable star data, and one way I'm doing this is using a 7-point, second-order Savitzky-Golay filter. I iteratively apply the filter 51 times (i.e. I apply the ...
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Which is the error of a value corresponding to the maximum of a function?
This is my problem: I use data observed with MUSE (which is an astronomical instrument provides cubes, i.e. an image for each wavelength with a certain range, link
) to extract a measure of redshift. ...
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Time Series Analysis and Forecasting of Astronomical data having a sinusoidal trend
I have data of an orbital parameter of a satellite for 456 days. I am treating this data as univariate time series data and wish to use time series models to forecast future values. However, this data ...
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Python Machine Learning: Measuring confidence in individual classifications
I am pretty new to machine learning. I am currently using sci-kit learn's DecisionTreeClassifier and RandomForestClassifier to look at astronomical data. It takes in a number of parameters and tries ...
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Should I use a paired sample t-test to compare two methods of measuring absorption lines?
Background
I'm doing a research project in astronomy and measuring equivalent widths of absorption lines using Gaussian fits from a star's spectrum in order to determine the star's chemical ...
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Is a visual estimate of homoscedasticity rigorous enough?
As part of my research in astronomy (quasar magnitudes at various wavelengths), I've been producing graphs such as the following:
The bottom plot on each graph shows the distribution of the residuals ...
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The probability of photon collision
I was reading a textbook and I couldn't figure out something that seemed really obvious:
Assume that the space is uniformly and randomly filled with stars, and the mean radial distance between the ...
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Advice to find faint periodic signals in time series data using deep learning methods
We are using few petabytes worth of time series astronomy data. The general aim is to find very faint periodic signals within it.
Our current method of processing this data is to do a Fast Fourier ...
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How to deal with changing variance in data sets
I've done an entry level stats course, so my knowledge is very limited in regards to this topic. I'm dealing with large datasets (~3000-9000 data points), and trying to pick signals out of the noise ...
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Bayesian inference for probability of finding extra-terrestrial intelligent life as more negative evidence is collected
Consider the problem of estimating the number of discoverable extra-terrestrial civilizations (in our galaxy, say), or the related problem of estimating the probability of discovering such a ...
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Machine Learning for optimization of configuration file
For my master's thesis I am using a 3rd party program (SExtractor) in addition to a python pipeline to work with astronomical image data. SExtractor takes a configuration file with numerous parameters ...
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Learn Bayesian inference applied to astronomy / astrophysics?
I'm looking for resources (books, articles, sites, etc.) to learn about Bayesian inference, but specifically applied to astronomy and astrophysics.
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What is the point of using an initial estimate when sigma-clipping data?
I am reading a paper that is discussing sigma clipping some velocity data, lets call it a set $V$, and it says:
The center at each iteration of the $3\sigma$ clipping is the biweight average, and $\...
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Statistics behind gravitational waves discovery [closed]
The recent gravitational waves result is a stunning feat for both physics and engineering. I suspect there may be much to admire on the statistics side as well. For example, the original paper states:
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How to check if two results are consistent
I'm looking at an astronomical object. In one observation, it does something (not relevant what :) 2199 times out of a possible 2936.
In another (later) observation, it occurred 2094 times out of a ...
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Method for fitting censored data in R
I have 320 data points - each has a redshift and a turnover-frequency, and I want to fit a correlation between them (a linear fit). However, 120 of the turnover-frequency values are upper limits. As ...
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Python Astronomy Censored Data in Lifelines [duplicate]
I am trying to find a correlation between a given data set containing redshifts and turnover frequencies (I have a list of 320 galaxies, and the redshift and turnover frequency (a turnover frequency ...
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Why are there more bayesians than frequentists in astrophysics?
I heard somewhere that in astrophysics, there are more bayesians than frequentists (although in general, I think that bayesian community is smaller). Is there something special about "astro" data what ...
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History: the role of statistics in astronomy
I recently boldly claimed in front of a group of fairly smart eighth grade students that astronomy contributed greatly to the foundations of statistics and many statistical concepts were invented for ...
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Which test is better suited to compare averaged versus single data sets
I have a light curve, that is photon count rate versus time, of an astronomical object. These data are periodic since the source signal is periodic. I can fold the data with the period and obtain an ...
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Calculate the number of trials to distinguish between 2 models
This sounds like a problem that has to be well known, but I can't find a good answer. I have tried another forum before I realized there was a stackexchange stats site. So here goes ...
I have two ...
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