Questions tagged [representative]
The representative tag has no usage guidance.
31 questions with no upvoted or accepted answers
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How can you evaluate the representativeness of a sample for a given distribution?
Problem:
I am looking for a metric to find the representativeness of a sample for a given distribution, being the representativeness of a random sample as the degree of capacity of the sample to ...
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Draw a stratified sample in panel data
Question: How can we draw a stratified sample in panel data context when the stratifying variables are not fixed over time?
Background: I have panel data on workers (id) over time (t). I want to draw ...
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Hand-picked items in the training set, good idea?
The training, validation and test sets for the classification problem I'm working on were randomly sampled from real data. Because of this, I am fairly confident that there are representative.
I want ...
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How to create representative training, validation, and test sets when working with time series data?
In my application, I am working with a relatively long time series of daily market index percentage returns (many years) and am trying to model the dependence structure of the returns from a pure time ...
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Training a classifier on a highly unbalanced class distribution?
I'm trying to train a text classification model that can predict label $A$ and $B$ accurately. However, 95% of the text examples in my dataset, which is representative of the kind of data I want my ...
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Representative Observation and Random sampling
Suppose that we have a cross-sectional data set drawn by random sampling.
Then, the data may represent our population of interests.
We can consider two subpopulations: male group and female group.
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When we up-sample the training set, don't we introduce selection bias?
When doing supervised machine learning in the health or medical domains, we often have a target class that is relatively rare (e.g., prevalence 1-10% of cases). There are a few techniques we can do to ...
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How to compare sample and population characteristics?
I have a sample $S1$ of 200 people, and I obtained a subsample $S2$ of 100 people by emailing a survey link to $S1$. So, $S2$ is a nonrandom subsample drawn without replacement.
In the sample $S1$, I ...
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Is there any appropriate technique to look for a continuous, representative part of a time series dataset?
I would like to know if there is any machine learning technique that could be used to solve the problem as follows. Imagine a time series dataset with several rows (observations) and many columns (...
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Finding the "most representative" variables of a population
Most polls use the so-called quotas method to obtain their sample. They draw candidates upon a large panel of people and add one-by-one each responding candidate to the sample unless a certain quota ...
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How to partition a sample into representative subsamples?
The problem is the following: take a sample $X$ of the general population $\Omega$. Each element of $\Omega$ (and hence, each element of $X$) is described by a vector of characteristics, each ...
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Representativeness of sample, distribution of age from sample compared to national sample
Please forgive my entry-level question. I have been slamming my head on the table for well over 3 hours now as I cannot seem to figure this one out.
I have a sample of n=450, population is about 17m....
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Can I use a stratified random sample to avoid getting a random sample that is clearly not representative?
This is a follow-up to a question of what to do if you get a sample that is clearly not representative [What if your random sample is clearly not representative? ]
I have a population of 800 in 25 ...
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Representative sample
My question is about representative samples. My population is parents of children attending public autism-specific schools. I distributed paper-based questionnaires to all the parents in the public ...
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Raking to converting a convenience sample to representative sample
I have a convenience sample of patients in a ZIP Code Tabulation Area (ZCTA) for whom I know their gender and age.
I also have census data for the ZCTA (in particular I have 1) the percentage of ...
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Relation between representativeness of a sample and sample size
Is there a relation between sample size and a representative sample? Does the sample size affect the representativeness of a sample?
Context: I used cluster sampling to get a sample of the study ...
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Sample size calculation of a national study
We want to conduct a national study to estimate a prevalence of certain disease. we still confused about the sample size calculation and the criteria of selecting a representative sample.
First: is ...
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Proper way to determine that one sample is better (more representative of a known population) than another sample
Please excuse me if this has been asked before, I searched and couldn't find what I was looking for. The basic setup of my question is this - I have data on all of the students for a school. I then ...
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Deciding by RMSE how many simulation results to use for a representative sample
So, I'm doing a brute force Monte Carlo simulation to vary certain parameters and running a model through a thermal computational test bed. At the end I get temperatures for every hour. We have ...
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227
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How can I calculate when a text corpus is representative of a language?
I am collecting and analyzing articles and other publications for building a text corpus.
I'd like to know how to calculate when my text corpus is representative of a field. That is, how many texts, ...
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Sample Representing a Different Population
I have two sets of populations: containing 1.5 million and 5.5 million units. I need to select a sample out of 5.5 million population so that the sample represents the 1.5 million population based on ...
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Finding a sample to represent a known population
Entire Population: 30,000
Known properties of population: Age, gender, height, weight,
Ideal representative sample size: ???
This is for a mailing list test group selection.
Problem constraints:
...
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How to construct homogeneous subsets table for nonparametric tests?
Does post-hoc for friedman tests or nonparametric testshave like a homogeneous subset table from SPSS? Mean doesn't represent it well so I tried using median but my data was zero-inflated so the most ...
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How to test that a sample of a discrete random variable is representative?
I am given a discrete random variable and several large samples from it. The methods how the samples are obtained are not truly random samples but are reasonable approximations to a random sample.
An ...
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Creating a representative sample
I'd like to create a representative sample from a larger population for monitoring (a hold-out control). I've thought of three approaches and am trying to select between them (plus I'm open to others)...
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When analyzing national surveys, do I always weight the answers with the expansion factor to get represenative results?
When analyzing national surveys, do I always weigh the answers with the expansion factor to get represenative results?
Alternatively, would it be wrong to just "weigh" each answer with 1 and ...
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Theory related to choosing high-information representative samples of a distribution
Let $X$ be a random variable of human height and suppose that $X$ is normally distributed.
If our goal is to select 'representatives' of the concept 'height', a reasonable way to choose representative ...
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Time dependent representation for time series events with different time gaps?
In natural language processing, we can treat characters as evenly spaced time series in RNN models where time gaps are independent of the sequence and only sequential positions matter.
If I want to ...
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Choosing data to compare collected data against
I currently have a sample of 30 data points of how long a specific process takes to complete when a particular issue occurs and am looking to compare these times to the times where it doesn't happen ...
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Representative Sample - Air travel passengers and gender ratio
I have a question regarding the ways to build a representative sample for a research study focusing on air travel passengers in 3 different world regions (NA, EMEA, APAC)
I think I should use the ...
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How can one control variables but ensure that the population is representative?
Usually, you want to control variables within a study. However, you also want to obtain a representative population to the population that you're measuring. How can one even strike a balance between ...
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