No imputation without representation
- URL: http://arxiv.org/abs/2206.14254v4
- Date: Wed, 30 Oct 2024 15:03:44 GMT
- Title: No imputation without representation
- Authors: Oliver Urs Lenz, Daniel Peralta, Chris Cornelis,
- Abstract summary: Missing values may in principle contribute useful information that is lost through imputation.
missing-indicator approach can be used in combination with imputation to instead represent this information as a part of the dataset.
We perform this experiment for three imputation strategies and a range of different classification algorithms, on the basis of twenty real-life datasets.
- Score: 1.7205106391379026
- License:
- Abstract: By filling in missing values in datasets, imputation allows these datasets to be used with algorithms that cannot handle missing values by themselves. However, missing values may in principle contribute useful information that is lost through imputation. The missing-indicator approach can be used in combination with imputation to instead represent this information as a part of the dataset. There are several theoretical considerations why missing-indicators may or may not be beneficial, but there has not been any large-scale practical experiment on real-life datasets to test this question for machine learning predictions. We perform this experiment for three imputation strategies and a range of different classification algorithms, on the basis of twenty real-life datasets. In a follow-up experiment, we determine attribute-specific missingness thresholds for each classifier above which missing-indicators are more likely than not to increase classification performance. And in a second follow-up experiment, we evaluate numerical imputation of one-hot encoded categorical attributes. We reach the following conclusions. Firstly, missing-indicators generally increase classification performance. Secondly, with missing-indicators, nearest neighbour and iterative imputation do not lead to better performance than simple mean/mode imputation. Thirdly, for decision trees, pruning is necessary to prevent overfitting. Fourthly, the thresholds above which missing-indicators are more likely than not to improve performance are lower for categorical attributes than for numerical attributes. Lastly, mean imputation of numerical attributes preserves some of the information from missing values. Consequently, when not using missing-indicators it can be advantageous to apply mean imputation to one-hot encoded categorical attributes instead of mode imputation.
Related papers
- On the Performance of Imputation Techniques for Missing Values on Healthcare Datasets [0.0]
Missing values or data is one popular characteristic of real-world datasets, especially healthcare data.
This study is to compare the performance of seven imputation techniques, namely Mean imputation, Median Imputation, Last Observation carried Forward (LOCF) imputation, K-Nearest Neighbor (KNN) imputation, Interpolation imputation, Missforest imputation, and Multiple imputation by Chained Equations (MICE)
The results show that Missforest imputation performs the best followed by MICE imputation.
arXiv Detail & Related papers (2024-03-13T18:07:17Z) - Iterative missing value imputation based on feature importance [6.300806721275004]
We have designed an imputation method that considers feature importance.
This algorithm iteratively performs matrix completion and feature importance learning, and specifically, matrix completion is based on a filling loss that incorporates feature importance.
The results on these datasets consistently show that the proposed method outperforms the existing five imputation algorithms.
arXiv Detail & Related papers (2023-11-14T09:03:33Z) - Polar Encoding: A Simple Baseline Approach for Classification with Missing Values [1.7205106391379026]
polar encoding is a representation of $[0,1]$-valued attributes with missing values.
It does not require imputation, ensures that missing values are equidistant from non-missing values, and lets decision tree algorithms choose how to split missing values.
We show that, in terms of the resulting classification performance, polar encoding performs better than the state-of-the-art strategies "multiple imputation by chained equations" and "multiple imputation with denoising autoencoders"
arXiv Detail & Related papers (2022-10-04T20:56:24Z) - Class-Level Logit Perturbation [0.0]
Feature perturbation and label perturbation have been proven to be useful in various deep learning approaches.
New methodologies are proposed to explicitly learn to perturb logits for both single-label and multi-label classification tasks.
As it only perturbs on logit, it can be used as a plug-in to fuse with any existing classification algorithms.
arXiv Detail & Related papers (2022-09-13T00:49:32Z) - Benchmarking missing-values approaches for predictive models on health
databases [47.187609203210705]
We conduct a benchmark of missing-values strategies in predictive models with a focus on large health databases.
We find that native support for missing values in supervised machine learning predicts better than state-of-the-art imputation with much less computational cost.
arXiv Detail & Related papers (2022-02-17T09:40:04Z) - Imputation-Free Learning from Incomplete Observations [73.15386629370111]
We introduce the importance of guided gradient descent (IGSGD) method to train inference from inputs containing missing values without imputation.
We employ reinforcement learning (RL) to adjust the gradients used to train the models via back-propagation.
Our imputation-free predictions outperform the traditional two-step imputation-based predictions using state-of-the-art imputation methods.
arXiv Detail & Related papers (2021-07-05T12:44:39Z) - Minimax Active Learning [61.729667575374606]
Active learning aims to develop label-efficient algorithms by querying the most representative samples to be labeled by a human annotator.
Current active learning techniques either rely on model uncertainty to select the most uncertain samples or use clustering or reconstruction to choose the most diverse set of unlabeled examples.
We develop a semi-supervised minimax entropy-based active learning algorithm that leverages both uncertainty and diversity in an adversarial manner.
arXiv Detail & Related papers (2020-12-18T19:03:40Z) - Handling Missing Data with Graph Representation Learning [62.59831675688714]
We propose GRAPE, a graph-based framework for feature imputation as well as label prediction.
Under GRAPE, the feature imputation is formulated as an edge-level prediction task and the label prediction as a node-level prediction task.
Experimental results on nine benchmark datasets show that GRAPE yields 20% lower mean absolute error for imputation tasks and 10% lower for label prediction tasks.
arXiv Detail & Related papers (2020-10-30T17:59:13Z) - Don't Wait, Just Weight: Improving Unsupervised Representations by
Learning Goal-Driven Instance Weights [92.16372657233394]
Self-supervised learning techniques can boost performance by learning useful representations from unlabelled data.
We show that by learning Bayesian instance weights for the unlabelled data, we can improve the downstream classification accuracy.
Our method, BetaDataWeighter is evaluated using the popular self-supervised rotation prediction task on STL-10 and Visual Decathlon.
arXiv Detail & Related papers (2020-06-22T15:59:32Z) - Learning with Out-of-Distribution Data for Audio Classification [60.48251022280506]
We show that detecting and relabelling certain OOD instances, rather than discarding them, can have a positive effect on learning.
The proposed method is shown to improve the performance of convolutional neural networks by a significant margin.
arXiv Detail & Related papers (2020-02-11T21:08:06Z) - On the consistency of supervised learning with missing values [15.666860186278782]
In many application settings, the data have missing entries which make analysis challenging.
Here, we consider supervised-learning settings: predicting a target when missing values appear in both training and testing data.
We show that the widely-used method of imputing with a constant, such as the mean prior to learning, is consistent when missing values are not informative.
arXiv Detail & Related papers (2019-02-19T07:27:19Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.