Questions tagged [subset]
One set, A, is a subset of another, B, if and only if all elements of A are elements of B.
125
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How to calculate confidence intervals in a subgroup of a weighted sample?
I have a weighted data sample (size : 20000) and I want to calculate a 95% confidence interval for the mean of a variable in the dataset, but only in a specific subgroup within this dataset (size of ...
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18
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Subgroups comparison
I have to compare two subgroups from the same population.
The two groups have partially the same records, so they are overlapping subsets of the same dataset.
Can I consider them as two independent ...
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0
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21
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Convergence of a subsequence of arrays of random variables
Consider $X(ij)$ for $i = 1, ..., n$ and $j = 1, ...,n$ be random variables.
I proved that for each i, the sequences $X($i$j)$ converge in distribution to random variable Y as $n$ tends to $\infty$. ...
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Does anyone know how to model selection for function on function linear model to find the best subset of functional covariate in R [closed]
Does anyone know how to model selection for function on function linear model to find the best subset of functional covariate in R
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Subset selection method for identifying predictors in multilevel modelling with longitudinal data
I am completing a time-lagged multilevel model to determine predictors of social functioning over time. I have 5 time points (not evenly spaced) with the dependent (or outcome) variable and all ...
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How to correlate a subset (gender) of a variable to another variable in a time series data?
So, I have a dataset something like this:
Date
VariableA
VariableB
2014/01
100
500
2014/02
200
700
2014/03
300
900
2014/04
400
1000
2014/05
500
1200
...
...
...
2022/12
50
10
After using the <...
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2
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250
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Number of subset from a sample space S is $2^n$?
I am working my way through the statistical inference textbook and am stuck on this question:
Suppose that a sample space $S$ has $n$ elements. Prove that the
number of subsets that can be formed ...
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1
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79
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Following Pearson correlation analysis how to compare subsets of the significant correlations
How can I statistically compare subsets of the significant correlations produced from Pearson correlation analysis (r-value, p-value) and Benjamini-Hochberg multiple testing adjustment (q-value)?
To ...
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1
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499
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Inconsistent handling of lonely PSUs in R's `survey` package?
There appears to be some inconsistent handling of lonely PSUs in R's survey package when calling svyglm on a subset of ...
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1
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53
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interaction term in Cox PH model
I have a question with regard to interaction term in Cox PH model.
I'd like to analyze the impact of variable A on cardiovascular (CV) event.
Variable A levels are different according to sex, although ...
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0
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193
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Discordant results using IPW and overlap weights (propensity score approach) in sub-group analyses
I am investigating the effect of a treatment on the risk of a disease (% disease=18.5% (515/2784)). To do so, I use a propensity score (PS) approach with two different weights methods: IPW (stabilized ...
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Model comparison on different datasets + Non-nested model comparison
I actually have two questions. Similar questions unfortunatelly do not answer mine.
1)I realize that with anova(model1,model2) one can only compare two models if ...
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71
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Should I use AIC / BIC or rather cross validation for discovering gov. equations through linear regression (SINDy)?
I want to use linear regression with very large design matrix for discovery of governing equations to i.e. physical systems. The design matrix would include potential terms that can be part of the ...
2
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1
answer
115
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Linear Regression - Data Subset with Lowest Mean-Squared Error?
Short version: given a linear regression dataset and an integer $K$, what data subset of size $K$ results in linear parameters with the lowest mean squared error on the entire dataset?
Long version: ...
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1
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21
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Determine the likelihood of occurrence of an activity within a subset
I have a monitor that measures dust concentrations around our neighborhood, and from this dataset I subset it into three scenarios to see which scenarios create the most dust. However, when I do this, ...
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1
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237
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When is subsetting survey data prior to analysis NOT a problem?
Survey researchers are typically advised to not subset their data prior to analysis because it will produce incorrect variance estimates. My understanding of the inferential issue is that removing ...
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Compare models from different data subsets [duplicate]
I'm looking to compare linear regression models from different data subsets in r. The models are not nested. I have a model from the complete dataset with sex as a factor and then 2 separate models ...
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2
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522
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Is it preferable to subset data to test specific hypotheses or specify a full model and run contrasts?
Let's say I have a 2x2 design where participants are either in condition A or condition B and, within each condition, either get exposed to exposure C or exposure D.
First, I want to test whether ...
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1
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56
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Logistic regression balanced dataset
I am quite inexperienced using logistic regression and am having trouble understanding my data and how the regression behaves. Here's the outline of my problem:
I have a (medical) test that gives a ...
7
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1
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127
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Is there a name for the increase in variance upon remeasurement after subsetting with a cut-off value?
Context: My problem relates to estimating effect sizes, such as Cohen's d, when looking at a subset of the population defined by a cut-off threshold. This effect size is the difference in two ...
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How to treat apples and oranges best in multiple regression analysis? One fits all regression model or separate sub models? [duplicate]
I have a data set ready for multiple regression analysis that consist of apples and oranges. Let's say the depended variable is fruit size and there is a bunch of independent variables (categorical &...
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2
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42
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Relationship between deterministc function of random variables
Given a discrete $P(X,Y,Z)$ let's call $\Omega$ the set of all deterministic functions $f: XYZ \rightarrow W$ and $\Omega'$ the set of all deterministic functions $f': XY \rightarrow V$. Is it correct ...
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1
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31
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How to isolate a linearly correlating subset from data?
I have a data set of a few thousand data points, and some of them show strong linear correlation. I would like to isolate these data points into their own subsets. What would be the best approach for ...
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128
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Difference between stratification and subset
This may be a duplicate question asked differently, I am curious to know the difference between performing an analysis by stratification on a variable and by subsetting the dataset based on that ...
4
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1
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981
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Probability problem - Probability to pick a subset divisible by 3
I'm trying to solve this puzzle but I get stuck. I thought about trying to use the law of total probability to solve intermediate problems with subset of size k but it didn't helped me that much. Is ...
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1
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Unsupervised Subspace learning for different Tasks
once we extract subspaces(subset of features) for a dataset using unsupervised learning, can we use them for any task I mean for classification, clustering, or outlier detection?
Is the selection of ...
2
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1
answer
282
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What is it called when we "zoom in" a data distribution?
Suppose we have a 2D distribution of shops in an area. For example, here is a heatmap density plot of (latitude, longitude) location of shops in a province:
Now suppose that we "zoom into" the ...
3
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0
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203
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Is it appropriate to include overlapping sub-scale scores and total-scale scores in a meta-analysis?
Question, brief
In a single multi-level meta-analysis, is it appropriate to include subscale scores (which represent part of a measure) in addition to total scale scores (representing the full ...
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456
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Q: AUC of each subgroup is smaller than overall AUC
I have a validation data set of 29242 patients, with known labels/health outcomes and predictions that were generated by some model. 28626 patients are negative and 616 are positive
The overall AUC is ...
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2
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615
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How to test that a subset of data is distributed no differently than original (discrete, not normal)
In the research I am doing we have initially had ~600 samples which had a certain distribution (not normal, although close). The characteristic of these samples that I am interested in is discrete (...
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50
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Compact encoding (vectorization) of unbounded sets
Question
I have a set of sets. Each set is unbounded.
I would like to find a methodology to encode (vectorize) each subset.
I am more specifically interested in memory efficient solutions.
...
2
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2
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Determine how similar groups of data are to each other
I have a pool of 15,000 unique* items. From that set, there are roughly 3200 sets of 60 items, selected non-randomly (in fact, for the sake of the framing of the question, let's say that each item is ...
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1
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Inferential considerations when comparing a group against the total
I want to compare the value of a subgroup against the same value in the total population in a regression setting. The easiest way to do it would be to treat the subgroup and the total dataset as two ...
10
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3
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How to calculate number of sets in Sigma Algebra
The example 1.2.2 of the book Statistical Inference by Casella and Berger states: if S has n elements, there are 2^n sets...(please see attached).
Could you please explain how the authors derived ...
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71
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relation between conditional probability of subset and set
Suppose $A\subseteq B $. Can we derive a relationship between P(X|A) and P(X|B) for some X? X is associated with A.
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2
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280
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Why do subset selection linear models have higher variance than the full model?
I do not get the meaning of this sentences from the Elements of Statistical Learning book when talking about subset selection methods before introducing shrinkage methods.
By retaining a subset of ...
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L sets and Probability theory
I am required to prove the following:
Let $L_1$ be the space of real-valued random variables on $(\Omega,\mathscr{A},\mathbb{P})$ which have finite expectation $\mathbb{E}(|X|)<\infty$ and let $...
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175
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Problem with significance of results from regression on subset of data
I have performed a hedonic regression with a database where all the variables are very significant and according to the calculations made in R with a squared R = 0.6123.
I have performed the same ...
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32
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Represent roles intersections
I have 11 roles, who defines rights (read, edit, write) on my application. For exemple I have "Inventory" who contains ressources_read and ...
0
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1
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1k
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What statistical distribution test to use for comparing Dataset and its subset? [duplicate]
I have two sets, A and B ,containing height of students. Set A contains height of all students in the class and Set B contains height of some students from the same class. Hence, Set B is a subset of ...
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1
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34
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Which is the event, sample and population, notation confusion
I am really struggling with the notation for this. Below is the slide material followed by what I think it means/where I get stuck.
"Some unknown real world quantity $\Theta$ takes values in $\Omega$....
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40
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Determining whether it matters which subset I pick from my dataset
I'm going to simplify my own research problem with the following example:
Lets suppose I have N=40 students in my classroom. I need to select 20 of them to participate in a national math competition. ...
0
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1
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26
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Resample dataframe by random subset of years
I have a dataset of 59 years worth of daily rainfall data.
I'd like to resample the data by 6 randomly selected years 1,000 times, using the entire year of data for each of the 6 years (so 2190 ...
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60
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Sample subsets with distribution proportional to elementwise product
I have a set of $n$ elements, $x_1,x_2,\dots,x_n$, each with a weight $w_1, w_2,\dots, w_n$. I want to sample a subset of fixed size $k$ such that the probability of drawing $\{x_a,\dots,x_b\}$ is ...
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401
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Unsupervised clustering of sequence of events to subsequences
I have a big dataset of M sequences of [1 - N] events, where each event has multiple properties (start date, end date, location, ...
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Why is the relationship between max(X,Y) and X and Y the way it is?
My textbook says that the above follows from the observation:
$\{W\leq w\}=\{X\leq w\},\{Y\leq w\}$,
How do we prove the above observation?
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51
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Survival analysis with incomplete data
I would like to estimate the association between exposure to an environmental contaminant and all-cause mortality. Unfortunately the dataset I can get access to is incomplete - exposure data are only ...
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k-means and (re?) standardisation of a sub-set
I have data which is customer purchases of items in each of three months:
I have summed the data over the three months for each customer;
calculated the proportion of purchases that each item ...
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1
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51
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Dividing datasets into fully-correlating subsets
I have a dataset of $N$ variables of which I know that (at least) one combination of their disjoint subsets results in non-negative correlation coefficients for all variables in these subsets. The ...
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149
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Finding p-value of similarity between 2 networks
So, I want to calculate p-value of a case if possible.
Suppose I have:
set A with 1,295 elements
set B with 493 elements
number of same element between set A and B (intersection) is 478
From each ...