Indicates questions asking about the use and meaning of specific technical words/concepts in statistics.

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0
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1answer
15 views

level of variable?

I was looking at this What does the level of a variable mean? I can only think of categorical variables with 2 values, like gender. Is there continuous variables with only 2 levels?
0
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0answers
6 views

Model name for regression with square root transformation on the response variable

Consider different transformations on the response variable. If log transformation is used: $$\log{Y} = \alpha + \beta X + \epsilon$$ The model is called log-linear model or semi-log model. My ...
0
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0answers
36 views

The Second Hearts Problem

Intro: According to the last part of these lecture notes, if we have a standard deck of playing cards and turn cards until the first heart appears, the probability that the next card is a heart is ...
3
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0answers
38 views

Definition of “meta-parameter” [duplicate]

What is meant by the term "meta-parameter"? Can a definition, informal and/or formal, be provided? For example, in reduced-rank regression, the rank ($r$) can be referred to as a meta-parameter of ...
1
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0answers
17 views

Are the terminologies of score and principal component in PCA equivalent? [duplicate]

I am confused with the terminologies of score and principal component in PCA, it seems they are equivalent but there is also some difference. Could anyone explain to me?
7
votes
1answer
384 views

What is skewness of a distribution?

What is skewness of a distribution? I ask it why any particular indices seem indecisive about symmetry, and in some case also about asymmetry.
2
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0answers
27 views

Why is the “sphericity assumption” in RM-ANOVA (constant variance of difference scores) called “sphericity”?

Why is the "sphericity assumption" in RM-ANOVA, i.e. the assumption of constant variance of difference scores, called "sphericity"? (This question was suggested in the comments to a related ...
3
votes
0answers
32 views

What is ordinary, in ordinary least squares?

A friend of mine recently asked what is so ordinary, about ordinary least squares. We did not seem to get anywhere in the discussion. We both agreed that OLS is special case of the linear model, it ...
4
votes
2answers
157 views

Does “improper” posterior or prior refer to a density function that does not integrate to 1 or to one that does not integrate to a finite value?

I am a bit confused about improper priors and posteriors. I have seen references that classify a prior or posterior probability density function as "improper" if the integral over infinite support ...
1
vote
1answer
120 views

What is the time between points called on a graph?

If I have a line graph that has a point for every day along the x axis and another graph that has a point for every month what is the name for the distance between points on the x axis? The _____ is ...
1
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0answers
21 views

When are observations not weakly exchangeable?

In the book "Common errors in statistics", I read the following statement Permutation tests only yield exact significance levels if the labels on the observations are weakly exchangeable under ...
2
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0answers
10 views

How do the terms non-stationarity, concept-drift and evolving data relate to each other?

I often see the terms non-stationarity, concept-drift and evolving data in the same context, as if they were interchangeable. Are they? Or is there some subtle nuance that I am missing?
9
votes
1answer
500 views

Why is a moment called a moment? [duplicate]

Someone told me that the term "moment" in Statistics comes from Physics. But I fail to understand how it relates to the definition of a moment of a force, which is a measure of its tendency to cause a ...
20
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6answers
1k views

In layman's terms what is the difference between a model and a distribution?

The answers (definitions) defined on Wikipedia are arguably a bit cryptic to those unfamiliar with higher mathematics/statistics. I am a high school student very interested in this field as a hobby ...
0
votes
1answer
10 views

Nomenclature Question on T-values and Z-scores

Do the following triplets of terms refer to the same concepts (respectively)? z-value, z-score, and z-statistic t-value, t-score, and t-statistic For example, is it the case that there is no ...
0
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0answers
26 views

Difference between (quantitative,qualitative) vs (discrete,continuous)

Could someone please clarify the difference between these seemingly interchangeable groups? (quantitative,qualitative) vs (discrete,continuous). Obviously they are not, but I cannot seem to pinpoint ...
1
vote
0answers
14 views

Digits that are insignificant by virtue of representing extremely small quantities within a much larger quantity: what are they called?

In computer science, sometimes we can measure run-times with high accuracy. As a hypothetical scenario, suppose a computation takes a week to run and we can measure the run-time accurate to the ...
1
vote
1answer
30 views

What is an “algebraic tail”?

The authors of this paper repeatedly use the term "algebraic tail" when describing some of the distributions they observed: ...the probability of remaining in a small, spatially confined region ...
15
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5answers
795 views

What's in a name: hyperparameters

So in a normal distribution, we have two parameters: mean $\mu$ and variance $\sigma^2$. In the book Pattern Recognition and Machine Learning, there suddenly appears a hyperparameter $\lambda$ in the ...
0
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0answers
18 views

Mixture Distribution of Multiples

Is there a specific name for a mixture distribution composed of a random variable and its multiples? Suppose we start with a "atomic" random variable $A$. I want to know what one calls the ...
1
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0answers
33 views

detecting the unknown canary [closed]

There is a metaphor "canary in a coal mine". The miners would keep the birds as an early warning system - if the bird suddenly died they would know something toxic was around and they could get out ...
1
vote
0answers
126 views

Testing difference between two portions of a time series with Chebyshev Theorem

I have a time series which presents two different patterns during time. These patterns are related to two different events that happen during the experiment. I can manually select the temporal ...
3
votes
4answers
147 views

Why do we say the outcome variable “is regressed on” the predictor(s)?

Is there some intuitive explanation for this terminology? Why is it this way, and not the predictor(s) being regressed on the outcome? Ideally I'm hoping that a proper explanation of why this ...
0
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0answers
12 views

The name for data reported by an interested party like a manager, parent, or doctor?

Can anyone help me find the right name for something? I get that we have "self-reported data", where a member of your sample is reporting their own values of a variable, but is there a name for data ...
0
votes
1answer
40 views

What is the meaning of the notation $P_\theta()$, where a probability has a subscript Greek letter?

What does theta subscript imply in e.g. this case: $$ P_\theta(T(x)=t) = 0 $$
10
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1answer
492 views

Why is left-skewed called negatively skewed and right-skewed called positively skewed?

I'm curious about the nomenclature: why is left-skewed called negatively skewed and right-skewed called positively skewed?
0
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0answers
15 views

Between high and low : name

I have a list : 1, 3, 5, 7,10. 1 is lowest and 10 is highest. Is there a term to define the numbers in between (3,5,7) All I can think about is inbetweeners
8
votes
2answers
150 views

Is bias a property of the estimator, or of particular estimates?

As an example, I often encounter students who know that Observed $R^2$ is a biased estimator of Population $R^2$. Then, when writing up their reports, they say things like: "I calculated Observed ...
0
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2answers
42 views

Terminology: Can “goodness-of-fit statistics” and “indicators” be used interchangeably?

I want to use several indicators to determine the goodness of fit of my model, such as R square, K-S, chi-square etc. What should I call them? Can I call them goodness-of-fit indicators? I see a ...
1
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0answers
35 views

How do you pronounce BOBYQA?

This question might seem subjective, but I ask because there is some precedent on this site. I and my colleagues have always pronounced the name of this optimizer as "bobby cue ay" (which also gives ...
7
votes
3answers
403 views

What is the difference between learning and inference?

Machine learning research papers often treat learning and inference as two separate tasks, but it is not quite clear to me what the distinction is. In this book for example they use Bayesian ...
2
votes
2answers
88 views

What is an isotropic (spherical) covariance matrix?

Could somebody explain to me in simple terms what an isotropic covariance matrix is? I can't find anything online.
6
votes
1answer
118 views

A name for operator-dependent cross-product

Suppose that we have a $\\n\times p$ matrix $\mathbf{M}$. Different transformations using different column-wise operators can lead to a new $\\p\times p$ symmetric matrix $\mathbf{S}$. For example, ...
0
votes
0answers
19 views

Difference between Discrimination, Calibration, Accuracy and Precision

I have trouble understanding these terms: a.) Discrimination. b.) Calibration. c.) Accuracy. d.) Precision. I really get confused with the books I am reading, ...
0
votes
1answer
35 views

Confusion regarding terminology related to the junction tree algorithm

As far as I understand, the "junction tree algorithm" is a general inference framework which roughly consists of the four steps 1) triangulate, 2) construct junction tree, 3) propagate ...
84
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16answers
7k views

What are the most misused statistics terms that we should care to correct?

Statistics is everywhere; common usage of statistical terms is, however, often unclear. The terms probability and odds are used interchangeable in lay English away from casinos and horse races, and ...
2
votes
1answer
48 views

“$X$ follows $Poisson(\theta)$ and an i.i.d. sample $X_1,…,X_n$ has been drawn”?

What does "$X$ follows $Poisson(\theta)$ and an i.i.d. sample $X_1,...,X_n$ has been drawn" mean? Does $X$ follows $Poisson(\theta)$ $\implies$ $(X_1,...,X_n) \sim Poisson(\theta)$ or Does $X$ ...
4
votes
1answer
51 views

Are there two definitions of the word bias?

I hear the term bias being thrown around a lot in statistical literature. For example, By using mean-wise imputation, we are adding bias to our estimate. Another example, The ...
1
vote
1answer
24 views

What do we call a set of Gaussians with the same covariance matrix?

What do we call a set of Gaussian distributions with the same covariance but different means? Is there a particular term for that? I mean the Gaussians are like: $N(\mu_1,\Sigma), N(\mu_2,\Sigma), ...
3
votes
2answers
98 views

Meaning of “missing by design” in longitudinal studies

I'm French and I'm reading an English book. I don't understand the term "when missingness is by design" — what does "by design" mean?
0
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1answer
44 views

What is the difference between stride and subsample in convolutional neural networks?

Is there any difference between stride and subsample in convolutional neural networks?
0
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0answers
14 views

tall, wide, big, small - qualitative descriptions

I was reading this link (link) where the authors say For "tall" data we cover a wide range of... and For "wide" data we discuss various forms... There is of course the ...
16
votes
3answers
379 views

Does this distribution have a name? $f(x)\propto\exp(-|x-\mu|^p/\beta)$

It occurred to me today that the distribution $$ f(x)\propto\exp\left(-\frac{|x-\mu|^p}{\beta}\right) $$ could be viewed as a compromise between the Gaussian and Laplace distributions, for ...
5
votes
1answer
78 views

Do we say that the $y_i$'s are i.i.d. if $n_iy_i \sim \text{Binomial}(n_i, \theta)$?

If $y_i$'s are independent and for given $n_i$, $$n_iy_i \sim \text{Binomial}(n_i, \theta)$$ Could we say that $y_i$'s are i.i.d.? If not, then what's the proper way to address such problems?
6
votes
1answer
435 views

Is regression with L1 regularization the same as Lasso, and with L2 regularization the same as ridge regression? And how to write “Lasso”?

I'm a software engineer learning machine learning, particularly through Andrew Ng's machine learning courses. While studying linear regression with regularization, I've found terms that are confusing: ...
0
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0answers
4 views

Term for incremental evaluation of data based on time?

When I test an algorithm's ability to classify dated samples over time, I will simulate it's use in a fictional past by iterating over each time period in order, training it on all samples dated ...
0
votes
0answers
18 views

Problems in notations in a paper on Bayesian space-time models

Suppose I have been given some process $Y$. Let $Y(s,t)$ denote the value of process at location $s$ and time $t$. For my experiment, I consider a model described as - $$Y(s,t) = \mu(s) + ...
0
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1answer
25 views

Meaning of “T-vector of time series values”?

I am currently studying a paper on Hierarchical Bayesian space-time models. In that, we have denoted $Y(s,t)$ to be the process of interest ate location $s$ and time $t$ in a gridded space-time. $Y(s, ...
0
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1answer
25 views

Terminology: Vector, attributes, and matrices in a dataset

I am confused about the terms "vectors", "attributes", and "matrix" when applied to a dataset. I know that attributes are the features or columns of the dataset, and the matrix is $N \times M$ data ...
3
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2answers
134 views

Translation of the term “data science” into Russian

What is "data science" in Russian? I'm interested in the context of a title of the job or a college course, or an academic paper. I'm not asking it in the Russian SE because it's a professional term, ...