# Questions tagged [subset]

One set, A, is a subset of another, B, if and only if all elements of A are elements of B.

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### Need help understanding paper by Jolliffe - various methods in choosing subsets for PCA

There's a paper I'm trying to base some work off of called Variable Selection and the Interpretation of Principal Subspaces which uses some various methods to choose subsets of variables. Their ...
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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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### 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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### 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 ...
285 views

### 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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### 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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### 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. ...
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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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### 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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### 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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### 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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### 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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### 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 ...
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### Are the assumptions of subset selection violated of all the data comes from a single person?

I’m interested in using machine learning techniques such as subset selection, lasso and ridge regression to predict which words an individual kid will get wrong. I have about 300 predictors and all my ...
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### Probability that 3 out of 4 sets have non-empty intersection

I have $4$ randomly sampled subsets from population set $S = \{1,2,...,100\}$. Each subset has size $24$. What is the probability that at least one element is common among $3$ out of $4$ subsets?
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### Dealing with many NA's in very large datasets for Lasso

I have a few very large and quite "dirty" (survey) datasets. Primarily, there are lots of NA's. These NA's are mostly the result of different questions being asked in different waves. It is ...
467 views

### finding expected value when a set is given and a subset of size n is chosen

I found an interesting coding challenge on pramp by a friend but I couldn't do it in time. Anyhow, it says given a set { 3,14,7,22,29,33} and random 3 element subset is generated each time and its ...
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### Vapnik-Chervonenkis Dimension

My question has to do with the VC dimension of the class of convex polygons with $m$ vertices. A solution to this problem is given in the following: Advanced Algorithms. Call the class of all ...
I have a presumably easy question for you, but I am a real newbie in statistics, so please be patient. I have a data set containing $N$ values that more or less follows a normal distribution. I need ...