Questions tagged [histogram]
A histogram is a graphical representation of the frequencies of a continuous variable. The variable is divided into bins and a bar is drawn for each bin, proportional to its frequency in the data.
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How to approximate histogram(f(x)) from histogram(x)?
I have a histogram of a variable x, and I would like to get the histogram of f(x). Let's just say the transformation function is ...
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K-Nearest-Neighbor classification with only distance/similarity matrices, is it possible?
I want to classify histograms/distributions using K-Nearest-Neighbor. I can measure distances/dissimilarities between the distributions (using euclidean distance, kullback-leibler divergence...), thus ...
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How long is a distribution considered normal?
I have a dataset of metric distances ($n=5800$) and plotted those as a histogram. My initial thought was that this distribution looks normal. But after performing a Shapiro Wilk test and plotting the ...
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Histogram and probability mass function
I have a dataset of a discrete random variable. My question is: Is the normed histogram(I divide the frequencies by the total number of samples) and the PMF is the same quantity? It seems they are. Is ...
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Scott's and Freedman–Diaconis rules of the thumb for selecting bin width - disatvantages
Scott's and Freedman–Diaconis rules of the thumb are based on the following formula:
In the article here it is stated that:
While these appear to be useful estimates for unimodal densities
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Averaging Histograms
I am currently running experiments which include measuring concentrations throughout an environment, producing a histogram as such:
Which shows the percentage of positions which have oxygen ...
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How to aggregate histograms for density estimation
Within a very large sensor network, each node does take measurements derived from a fixed number of samples taken at a high frequency from an instrument. The number of measurements send to an ...
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Why is "using counts of a frequency table as data" for a histogram a "mistake"?
The textbook, The Practice of Statistics, states the following as a "common mistake" when making histograms:
Don't use counts (in a frequency table) or percents (in a relative frequency table) as ...
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y-axis ticks of distribution plot
Can I know what are the ticks at y axis mean?
I created a distribution plot of titanic['Age'] data from.Kaggle Titanic Data
How to learn more about distribution of age column from the dataset from ...
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A question about Histogram-to-distribution transformation
I have done a simulation with 1 million runs on Matlab. I have got a histogram for this. Using Matlab command hist(X), (where X is the 1 million samples as results ...
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Why do we subtract the $cdf_{min}$ in this step of histogram equalisation?
In my question I am referring to histogram equalisation as it is described in the wikipedia article in this example here.
Given an grey image $I$ of size $M \times N$, in histogram equalisation one ...
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Choosing center of histogram bins for fitting
I have a bimodal distribution, and if plotted with Mathematica it looks like this:
Now, the lowest value from the actual data is 8196 and 690720, but as seen in the plot, Mathematica lets the data ...
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Relative frequency question
I am a new user here, and I need some help getting started with the following question:
The textbook answers are a. $19$ and b. $20$. How do I begin this question? I am a beginner in statistics. :)
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95% confidence interval error bars of normalized histogram
I have observational data from a satellite and I am studying a certain phenomenon. I have locational data of these phenomena (let's call this data set A). I have divided the data into histogram bins ...
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SVM classification on distance matrix
How can I do an SVM classification when I only have a distance matrix (pairwise matrix)?
Edited: I want to classify my data in two groups: healthy and sick. My original data are histograms (which are ...
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How to analyze size frequency data from over 70 sites
When I started my PhD, I had virtually no prep-time. My advisor needed me in the field and told me to go grab samples. As such, my planning wasn't the best, so sorry if this is a completely terrible ...
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What is a "Nominal Type Histogram" and "Shuffling Invariant Property"?
I'm reading this paper about comparing histograms ["Comprehensive Survey on Distance/Similarity Measures between Probability Density
Functions" by Sung-Hyuk Cha] that writes in the introduction:
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What is histogram classifier and how to use it? [closed]
This question is about the assignment on my ML course..
I have been given two continuous data in a normal distribution and predict the values of both for class labels(m/f) in 2 steps:
build a ...
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Outlier detection for skewed data
I have a dataset as below:
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4.9338
4.9563
4.993
4.9947
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5.2932
4.981
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4.982
4.982
4.982
4.982
4.983
4.983
4.984
4.984
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How to divide the data to analyze [Histograms in R]
I am working on the data of a contest, of 85 days duration, where all the participants could choose to participate or not every day.
The distribution seen through a histogram is:
[Histogram with the ...
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How to standardize histogram?
I have known quadrature points (X_q) for q = 1, ..., Q and known frequency (A_q) at each point. I want to rescale X_q and A_q, so that I have the new X_q_new and <...
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Selecting the Number of Bins in a Histogram: A Decision Theoretic Approach
I am attending a course about Python and as supplementary readings for the lesson about plotting histograms the Professor suggested the following article: Selecting the Number of Bins in a Histogram: ...
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Why is the $x$ axis for a histogram labeled "bin"?
When talking about histograms, why do we refer to the x-axis as "bin"?
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Distance Between 1-D Histograms and Binning
In order to calculate the distance between two 1-D histograms, they must have the same number of bins. I'm wondering if it's preferable to have more or fewer bins for such calculation.
For example, ...
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Can the 'bin size' in a histogram be thought of as a regularity constraint?
When thinking about a histogram as an estimate of the density function, is it reasonable to think of the bin size as a parameter that constrains the local structure of that function?
Also, is there a ...
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Convert a beta distribution to Poisson distribution
I need a Poisson distribution in an application, but in that application the only available functions for generating distributions are Beta, Uniform, and Normal functions. Now, I am thinking is there ...
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What is the correct way to modify the bin-counts given a threshold for a chi-squared test?
When performing a chi-square test, one inputs the expected counts (via integrating probability distribution over respective bin bounds) and observed counts into the chi-square formula (denoted below).
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Why do these two logarithmic binning methods give different results? (in R)
Problem
I am working on a problem involving logarithmic binning. I have a dataset consisting of individuals that have a size value and a production value. I am using an algorithm to logarithmically ...
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Is there a method to determine the optimum bin size to use for a grouped frequency data?
I need to plot the empirical pdf of the data:
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How does one graph the PDF of a variable having a mixed discrete-continuous distribution?
Simple question: how to graph the PDF of a mixed discrete-continuous distribution?
Does it require one graph for the continuous portion and a separate graph for the discrete?
Also, is such a beast ...
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How to produce a normalized cumulative histogram?
I am having trouble understanding the proper method to calculate specific histograms, specifically with regard to cumulative and normalized histograms. If I want to calculate a normalized cumulative ...
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Generating sequence matching distribution from histogram
One of the developers of lobste.rs recently posted some interesting data showing the distribution of votes and comments for stories on the site. In particular, the posted results give a histogram of ...
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How do I estimate the ERROR for a histogram?
I am sampling a random variable from a system so as to find the underlying distribution. To do so, I can plot either a histogram, or a kernel density estimate.
Either way, how do I indicate the ...
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Comparing the integral of a histogram and its distribution function
I asked a question here but I did a rather poor job of explaining my problem the question was poorly formed.
If I have some histogram with $N_{total}$ number of total data points, and $N_{bins}$ ...
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Area under a histogram [duplicate]
Perhaps a basic question, if I have an un-normalised histogram, my understanding was that the integral is simply the total number of points.
If I then fit a curve over the the histogram, then surely ...
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Why are mean and standard deviation not exactly as I entered on R?
We're looking at a random sample of the heights of 100 males at our school. These are our instructions:
Click on Distributions -> Continuous distributions -> Normal distribution -> Sample from ...
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Exaggerated Distribution on Sampling from a Density Estimator
I'm training a NADE on a dataset and then sampling from it as described in the paper. My (binary) feature vector that represents each point in the dataset contains a concatenation of various binary ...
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How to evaluate a histogram?
Let's say I have the histogram above which reports performances of some neural networks. The y axis is the bin size, while the x axis is the error, so low errors = high performance.
Out of these 15 ...
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Assess whether the generated data follows the distribution
Using the Inverse function method I managed to draw a sample of 500 random data from a Cumulative distribution function. $f(x)$,$F(x)$ and $F_X^{-1}(u)$ are as follows:
$$f_X=\frac{x}{5}exp\left({\...
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Why do we use density scale when constructing histograms with unequal class widths? [duplicate]
When constructing a histogram with equal class widths, we mark the class boundaries on the horizontal axis and draw above each interval a rectangle whose height corresponds to the relative frequency ...
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How can I characterize a histogram/distribution with a single value?
I have histograms/distributions like the following that I would like to characterize/summarize by one or maybe two number(s). A mean +/- std would be one such example, but is there something better ...
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How to compute optimal binning for two histograms
I am plotting two histograms on top of one another (using matplotlib, but that is tangential to my question). My current approach is to compute the mean of the optimal bin widths for each histogram ...
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Differential histogram bin calculation
I want to be able to minimize a difference between two distributions $P(x|\theta)$ and $Q$. I can choose Q (e.g. to be a Gaussian normal), but $P(x|\theta)$ is an unknown distribution, so I am ...
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How do I Estimate Joint Entropy Using a Histogram?
I am trying to estimate the entropy for two time series, defined by random variables $X$ and $Y$, each distributed according to an unknown PDF which is to be estimated empirically (using a histogram ...
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What type of distribution to use?
This is my first post here.
I am making a financial model in excel of the feasibility of a project.
Herefore I need to make some assumptions. One of those assumptions would be the fuel price and how ...
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Normal distribution of raw data in multiple regression necessary?
Here is a distribution of a continuous independent variable I intend to use for multiple regression analysis displayed on a histogram.
I understand that a normal distribution of residuals is a ...
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Convert Discrete Histogram to Continuous Function
Suppose, I have a histogram (or a "discrete" frequency counter):
X = {0.1: 3, 0.2: 5, 0.41: 1, 0.45: 5, 0.5: 3, 0.7: 9}
What is the best possible way to convert ...
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Numerical method to compress empirical probability distribution
I am trying to grapple with the following problem.
I have an application that develops empirical distributions. In essence, I end up with a histogram of equally spaced $x$ values, with both a $max$...
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Derivation/Explanation of the Freedman-Diaconis Rule
Can anyone provide a good derivation of the FD rule? Or explain why it is a good way to define the bin widths of a histogram. Are there any other similar rules and how do they compare?
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How to make a GMM from a Histogram to give a probability?
I have a histogram that looks like the following:
From the data, I can see that this histogram shows two obvious curves. If I make the claim that they are from two Gaussians, how can I make a ...