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Questions tagged [subsampling]

116 questions
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errors with subsample 0.0.6 in python2.6

I am trying to run the subsample0.0.6 package in python2.6.6 (to be able to run something like "> subsample -n 1000 big_data.csv" in python) after installing subsample it seems to work at first after I check with "import subsample", but then when I…
aaf6
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could not calculate the dimensions after pooling and subsampling in the famous Convolutional neural nets example

The above image is from a pdf by Yann LeCun, titled "Hierarchical Models Of Perception and Reasoning" I am not able to understand the how the layer 2 is 14X14 feature maps? How can 75X75 matrix with 10X10 pooling and 5X5 subsampling gives 14X14…
Abhishek
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Is it possible to adjust a jpeg subsamping with php?

I'm making an image uploader for a client and working on minimizing file size. Already adjusting quality, setting optimize and progressive, removing exif data, just looking for a way to adjust subsampling and smoothing. Just wondering if there is a…
Jimmy Long
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By household, keep data only if observations started after Feb. 2000 - Stata

I am working in Stata and have data that lists out portfolios(houseID), the year and month, the stockID and the stock's return. The data spans several years. And looks like: I am essentially trying to isolate a sub-sample of the data. I would…
user3196098
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How to subsample YCbCr in 4:2:0 format in JPG files? [PHP]

For a mathematical bachelor thesis I am trying to code a simple JPG encoder in PHP. After after hard work I made it to create a script that reads out the colors of a PNG file, transforms it to YCbCr Color Format and does the Discrete Cosinus…
sgnd
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Statistical test constructed by subsampling is not popular?

I found this book: https://sites.stat.washington.edu/jaw/COURSES/580s/582/HO/Lehmann_and_Romano-TestingStatisticalHypotheses.pdf Chapter 15 lays out how to construct statistical test by subsampling. It seems a very convincing method, and can at…
Sean
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Efficient way to create stratified subsamples of a data frame, depending on frequency of a category

I want to create a sub-sample of data frame df, depending on the frequency of a given category in one of its columns, e.g. a. Let's assume we have a data frame like this: df <- data.frame(a = rep(1:4, c(3, 9, 4, 8)), b = runif(24))…
tpetzoldt
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Subsampling a species x sample matrix - ecology

I have an abundance of data for 239 species from 140 sites. Species are columns, and sites are rows. The matrix looks like the simplified one below. I want to sample from each site 5 individuals without replacement. Is there any function that…
Anadara
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How to subsample a data set to determine new detection rates

I have been tasked with subsampling a data set of cameras to determine whether we can get away with fewer cameras in our camera grid. The dataset already has detection rates for each species at each subplot. I have never subsampled before in R and…
Sierra McMurry
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Reweight observations after subsetting

I have a dataset containing a weight column, which I would like to subset while adjusting these weights to keep it representative of the original dataset. Let us say I have the dataframe : data.frame(Age=c(10,20,30,25,50,60,40), …
Kamaloka
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Subsampling from a set with the assumption that each member would be picked at least one time in r

I need a code or idea for the case that we have a dataset of 1000 rows. I want to subsample from rows with the size of 800 for multiple times (I dont know how many times should I repeat). How should I control that all members would be picked at…
Nmgh
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After Effects: How to export H.264 / MP4 / 4:2:0

I need to export an animation from after effects as a H.264 mp4 with a chroma subsampling of 4:2:0. Media encoder is available. Both AE and ME do not seem to give me an option to adjust the chroma subsampling. I read that 4:2:0 should be default,…
Sandro
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Select randomly percent of datasets in each percent of epochs

I have a model that should train with 25000 data in 50000 epochs. I want to train with the percentage of datasets for a percentage of periods for example it trains for 10 first epochs only 1000 random data than for 10 next epochs, 1000 random…
diamond
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Subset with fixed proportion of categorical variables

I have a problem that I cannot seem able to solve. I have a dataset with two categorical variables: Gender (Male vs Female) and Smoking status (Smokers vs Non-smokers). The dataset contains 60% Male and 50% of Smokers. df =…
Giulia
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subsampling formula skipgram NLP

I'm studying how to implement a Skip-Gram model using Pytorch, I follow this tutorial, in the subsampling part the author used this formula: import random import math def subsample_prob(word, t=1e-3): z = freq[word_to_ix[word]] / sum_freq …
Dogo-San
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