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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Mallows distance hypothesis test: p-value =?
I am using Mallow's Distance (normalized Earth Mover's Distance) to characterize the similarity between two histograms. This is working very well, but I would like to identify a specific cut-off where ...
3
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1answer
74 views
How to test for normality of growth disturbances in chemo treatment?
I'm a med student, conducting a retrospective analysis of weight/growth disturbances during chemo treatment.
I wonder, if I should:
assume, that growth is a variable normally distributed across the ...
2
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1answer
46 views
Estimation of mean, variance and mean squared error of a histogram that poorly models real distribution
I'm having a basic statistics problem. I'm running an experiment using a photon counting detector to measure a diffraction pattern. I want to calculate the centroid of each diffraction spot and the ...
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1answer
48 views
Plotting 0 in a log scaled axis
I have a very large and sparse dataset of spam twitter accounts and it requires me to scale the x axis in order to be able to visualise the distribution (histogram, kde etc) and cdf of the various ...
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2answers
60 views
Should the predictor variables be normally distributed for Poisson glm?
This is probably a really basic question, but it's the first time I've created a model that defines Poisson as its error family.
In setting up my variables to make the model, should I be concerned ...
4
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1answer
99 views
Histogram with uniform vs non-uniform Bins
This question describes the basic difference between a uniform and a nonuniform histogram. And this question discusses the rule of thumb for picking the number of bins of a uniform histogram that ...
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51 views
Confusion related to histogram density estimation
I have some confusion related to how the density is estimated from the histogram. I have attached the screenshot of the paper as well. Any insights
I didn't get why you divide it into cubes and why ...
3
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2answers
147 views
Doane's formula for histogram binning
I'm implementing various algorithms to estimated the best number of bins to use for histograms. Most of the ones I am implementing are described on the wikipedia page:
...
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1answer
106 views
R: Density estimation vs Histogram Estimation
To draw random samples from a custom distribution, I recall reading that KDE's are better than histograms. (See hadley's comment here.)
When I experimented in R, I am finding that the KDE method ...
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3answers
303 views
Is it appropriate to plot the mean in a histogram?
I have a Really Stupid Question:
Is it "okay" to add a vertical line to a histogram to visualize the mean value?
It seems okay to me, but I've never seen this in textbooks and the likes, so I'm ...
3
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1answer
108 views
QQ plot is consistent with normality when subgroups are non-normal
I have read that for a one way ANOVA, you should check that the model residuals are normally distributed. If the variance of each group is homogeneous then this implies that the residuals with each ...
5
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2answers
248 views
QQ plot does not match histogram
I have a histogram, kernel density and a fitted normal distribution of financial log returns, which are transformed into losses (signs are changed), and a normal QQ plot of these data:
The QQ plot ...
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0answers
104 views
Freedman-Diaconis Rule
The Freedman-Diaconis Rule says that the optimal bin size of a histogram is $$ \text{Bin Size} = 2 \cdot \text{IQR}(x) n^{-1/3}$$ where $x$ is the data and $n$ is the number of observations in the ...
3
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1answer
148 views
Chi-squared test for histogram data after doing an averaged shifted histogram
I have a data set of 903 continuous observations, that I graphically visualize with a histogram. The bin and width values could be optimized, but it is logical from the distribution that I have a ...
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1answer
235 views
Bhattacharyya distance for histograms
One of the ways to measure the similarity of two discrete probability distributions is the Bhattacharyya distance.
In computer vision, for example, it is used to evaluate the degree of similarity ...
24
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3answers
10k views
Assessing approximate distribution of data based on histogram
Suppose I want to see whether my data is exponential based on a histogram (i.e. skewed to the right). Depending on how I group or bin the data, I can get wildly different histograms. One set of ...
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2answers
65 views
rounding when making a histogram
Suppose that when making a histogram, one encounters a datum at a bin boundary. Is there a convention on how to round it? For example, suppose my data are integer percentages, running from 0% to ...
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2answers
129 views
Histogram of uncertain data
I have a set of values, each of these values has its own mean and variance. I want to be able to account for this variance when I plot the histogram of the means. Something like an error bar on the ...
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1answer
133 views
Converting spectral data to RGB and normalizing appropriately
I have spectral data which tells me how strong of a response in RGB values for some color-space I get for a particular wavelength of light.
Typically, if I want "plain" white light, I'd have to sum ...
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47 views
Plotting a histogram estimate together with an analytical solution of the mean and covariance parameters
How do I plot a histogram estimate of this marginal distribution p(x1):
...
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0answers
38 views
Calculate standard deviation of data within each bar of a histogram [duplicate]
I have data with which I plot a histogram.
I would like to know the standard deviation of each bar of histogram.
Do you think it is an acceptable method to divide the samples into sub-samples for ...
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0answers
77 views
On the uniform convergence of relative frequencies of events to their probabilities
I have read the article by Vapnik, Chervonenkis "On the uniform convergence of relative frequencies of events to their probabilities" Theory of Probability and Its Applications, vol XVI, n. , 1971.
...
4
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1answer
238 views
Disagreement between normality tests and histogram graphs
My data consist of compaction measurements from 3 different cell types (X,Y, and Z). My goal is to know whether there are "significant" differences between these measurements, so I have tested for:
...
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2answers
85 views
Defining the “uniformity” of a dataset
I am working on a few algorithms where I have a list of $N$ samples. Currently I have plotted these into a histogram and have a view of how uniform the values are distributed within an interval, which ...
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2answers
897 views
How to plot a mekko chart in Excel?
So a question you will have from here!
Q: What is Mekko?
A. Its like a histogram. The bar chart can show information in two axes. Normally in a bar chart the y axis shows the variation and x shows ...
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1answer
195 views
Histogram question: How do we choose a perfect histogram?
20 students from a school were randomly selected to study the dollar
amount that they spend on purchasing soft drink in a typical week. The data
collected (in dollars):
...
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2answers
402 views
Graphical representation of weekly spending
What is the correct graphical representation for these data of weekly spending (in dollars) on soft drinks for 20 people:
...
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0answers
31 views
References regarding rules for multidimensional histograms
Can someone give me references on the theory of histograms applied to multivariate data? Are there any rules like the one dimensional Freedman-Diaconis available for the high dimensional case? What ...
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2answers
167 views
Is there an upper limit on the number of intervals in a histogram?
I've read several articles and excerpts from books that explain how to choose a good number of intervals (bins) for histogram of a data set, but I'm wondering if there's a hard maximum number of ...
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1answer
53 views
Grading a range of data
I am new to data mining and I am exploring ways to divide a range of data into bins. It would be much easier to search for the algorithms if I knew the scientific term for this job (ranking maybe?). ...
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0answers
43 views
Blind deconvolution of histogram
I am not sure that this is good forum to ask, but dunno where to ask.
I have a file with histogram data collected from cytometer. The problem is that these data contain several signals and I want to ...
2
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2answers
183 views
Rules of Thumb to choose an initial number of class intervals and refine that choice (potentially automatically)
I was wondering if there are established rules of thumb (or algorithms) that, given a set of observations can help:
choose an initial number of class intervals.
refine that choice to a better ...
2
votes
2answers
124 views
Determine range that contains given ratio of data points
I'd like to determine the "representative" range for a series of data points. For example, I'd like to know the range where 98% (or any other given ratio) of points are located. I could have used the ...
5
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2answers
223 views
How to estimate the third quartile of binned data?
Is there any technical trick to determine the third quartile if it belongs to an open interval which contains more that one fourth of the population (so I can't close the interval and use the standard ...
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2answers
375 views
How to 'intelligently' bin a collection of sorted data?
I am trying to intelligently bin a sorted collection. I have a collection of $n$ pieces of data. But I know that this data fits into $m$ unequally sized bins. I don't know how to intelligently choose ...
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0answers
213 views
Calculating and comparing histograms of complex numbers
If I have a 1D sequence of complex numbers with real and imaginary parts, how can I compute the histogram of this sequence? Do I separately compute the histogram of both the real and imaginary parts?
...
5
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1answer
219 views
Сonfidence interval of histogram probability density function estimator
There is a circle of radius $R$ and a sequence of points within it. I'm going to estimate a PDF of appearing at elementary area at the distance $D$ from the centre of the circle using a realization of ...
6
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2answers
1k views
How is Poisson distribution different to normal distribution?
I have generated a vector which has a Poisson distribution, as follows:
x = rpois(1000,10)
If I make a histogram using ...
4
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0answers
183 views
What PDF should be fit to a rank histogram?
A Rank Histogram (or Talagrand Diagram) is a neat way of measuring whether your numerical model is giving appropriate variance. It's used for weather and climate forcasting, where you only have one ...
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1answer
152 views
exact Monte Carlo simulation of a large sample histogram
(Asked this on MathOverflow, got redirected here)
Say I want to create a histogram of $N$ samples from some simple compactly supported distribution on $\mathbb{R}$, where $N$ is very large, say $N = ...
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2answers
221 views
Does the samples mean and the histogram mean have to be the same?
I'm reading this book. Here, he gives me a method for calculating the mean:
Here he introduces a new method of calculating the mean through histogram:
He says that now we will count and index the ...
3
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1answer
399 views
Confidence interval for the height of a histogram bar
Let X1, X2, ..., Xk be an i.i.d. sample of a random variable X. I plot these in a histogram and would like to include a confidence interval for the height of each histogram bar. Do you know how to go ...
4
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2answers
295 views
How to perform a non-equi-spaced histogram in R?
From the R docs for hist:
R's default with equi-spaced breaks (also the default) is to plot the
counts in the cells defined by breaks. Thus the height of a rectangle
is proportional to the ...
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1answer
176 views
How to create a histogram smart
I need to make a histogram of employees in firms across the country.
My goal is to examine the extreme observations and there is of course a lot in the beginning and very few in the end so I can't ...
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1answer
378 views
Identifying a number of significance from a histogram
I'm creating a program that identifies trending music artists that uses Twitter metrics. I have data in a histogram format that represents the frequency of twitter @mentions of an artist for the last ...
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2answers
1k views
Separating the populations in a bimodal distribution
I have a data set which displays a bimodal distribution. This was determined by plotting a histogram of the frequency vs number.
I now need to separate the two original populations and therefore ...
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votes
3answers
253 views
Shape of distribution of histogram
If we have the following histogram:
And, want to describe it based on one of the following options, which one do you think is correct? Why?
positively skewed
symmetric
none of the above ...
7
votes
1answer
548 views
Goodness of fit for 2D histograms
I have two sets of data representing stars parameters: an observed one and a modeled one. With these sets I create what is called a two-color-diagram (TCD). A sample can be seen here:
A being the ...
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0answers
59 views
How well the experiment would do in excluding alternative hypothesis?
The experiment has $N$ observations $N_i$ which are Poisson Distributed random variables (i.e. we have histogram with $N$ bins. The width of bins is not fixed so I can adjust it ) . I have two ...
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2answers
1k views
Generate a probability distribution from a histogram with two peaks in matlab
I have a histogram with two peaks and I want to generate the corresponding probability distribution. I have used the following MATLAB code:
...
