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Advances in neuroimaging, genomic, motion tracking, eye-tracking and many other technology-based data collection methods have led to a torrent of high dimensional datasets, which commonly have a small number of samples because of the intrinsic high cost of data collection involving human participants. High dimensional data with a small number of samples is of critical importance for identifying biomarkers and conducting feasibility and pilot work, however it can lead to biased machine learning (ML) performance estimates. Our review of studies which have applied ML to predict autistic from non-autistic individuals showed that small sample size is associated with higher reported classification accuracy. Thus, we have investigated whether this bias could be caused by the use of validation methods which do not sufficiently control overfitting. Our simulations show that K-fold Cross-Validation (CV) produces strongly biased performance estimates with small sample sizes, and the bias is still evident with sample size of 1000. Nested CV and train/test split approaches produce robust and unbiased performance estimates regardless of sample size. We also show that feature selection if performed on pooled training and testing data is contributing to bias considerably more than parameter tuning. In addition, the contribution to bias by data dimensionality, hyper-parameter space and number of CV folds was explored, and validation methods were compared with discriminable data. The results suggest how to design robust testing methodologies when working with small datasets and how to interpret the results of other studies based on what validation method was used.
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Imports:
# All Imports
import os
from matplotlib import pyplot as plt
import pandas as pd
from sklearn.calibration import LabelEncoder
import seaborn as sns
import matplotlib.image as mpimg
import cv2
import numpy as np
import pickle
# Tensflor and Keras Layer and Model and Optimize and Loss
import tensorflow as tf
from tensorflow import keras
from keras import Sequential
from keras.layers import *
#Kernel Intilizer
from keras.optimizers import Adamax
# PreTrained Model
from keras.applications import *
#Early Stopping
from keras.callbacks import EarlyStopping
import warnings
Warnings Suppression | Configuration
# Warnings Remove
warnings.filterwarnings("ignore")
# Define the base path for the training folder
base_path = 'jaguar_cheetah/train'
# Weights file
weights_file = 'Model_train_weights.weights.h5'
# Path to the saved or to save the model:
model_file = 'Model-cheetah_jaguar_Treined.keras'
# Model history
history_path = 'training_history_cheetah_jaguar.pkl'
# Initialize lists to store file paths and labels
filepaths = []
labels = []
# Iterate over folders and files within the training directory
for folder in ['Cheetah', 'Jaguar']:
folder_path = os.path.join(base_path, folder)
for filename in os.listdir(folder_path):
file_path = os.path.join(folder_path, filename)
filepaths.append(file_path)
labels.append(folder)
# Create the TRAINING dataframe
file_path_series = pd.Series(filepaths , name= 'filepath')
Label_path_series = pd.Series(labels , name = 'label')
df_train = pd.concat([file_path_series ,Label_path_series ] , axis = 1)
# Define the base path for the test folder
directory = "jaguar_cheetah/test"
filepath =[]
label = []
folds = os.listdir(directory)
for fold in folds:
f_path = os.path.join(directory , fold)
imgs = os.listdir(f_path)
for img in imgs:
img_path = os.path.join(f_path , img)
filepath.append(img_path)
label.append(fold)
# Create the TEST dataframe
file_path_series = pd.Series(filepath , name= 'filepath')
Label_path_series = pd.Series(label , name = 'label')
df_test = pd.concat([file_path_series ,Label_path_series ] , axis = 1)
# Display the first rows of the dataframe for verification
#print(df_train)
# Folders with Training and Test files
data_dir = 'jaguar_cheetah/train'
test_dir = 'jaguar_cheetah/test'
# Image size 256x256
IMAGE_SIZE = (256,256)
Tain | Test
#print('Training Images:')
# Create the TRAIN dataframe
train_ds = tf.keras.utils.image_dataset_from_directory(
data_dir,
validation_split=0.1,
subset='training',
seed=123,
image_size=IMAGE_SIZE,
batch_size=32)
#Testing Data
#print('Validation Images:')
validation_ds = tf.keras.utils.image_dataset_from_directory(
data_dir,
validation_split=0.1,
subset='validation',
seed=123,
image_size=IMAGE_SIZE,
batch_size=32)
print('Testing Images:')
test_ds = tf.keras.utils.image_dataset_from_directory(
test_dir,
seed=123,
image_size=IMAGE_SIZE,
batch_size=32)
# Extract labels
train_labels = train_ds.class_names
test_labels = test_ds.class_names
validation_labels = validation_ds.class_names
# Encode labels
# Defining the class labels
class_labels = ['CHEETAH', 'JAGUAR']
# Instantiate (encoder) LabelEncoder
label_encoder = LabelEncoder()
# Fit the label encoder on the class labels
label_encoder.fit(class_labels)
# Transform the labels for the training dataset
train_labels_encoded = label_encoder.transform(train_labels)
# Transform the labels for the validation dataset
validation_labels_encoded = label_encoder.transform(validation_labels)
# Transform the labels for the testing dataset
test_labels_encoded = label_encoder.transform(test_labels)
# Normalize the pixel values
# Train files
train_ds = train_ds.map(lambda x, y: (x / 255.0, y))
# Validate files
validation_ds = validation_ds.map(lambda x, y: (x / 255.0, y))
# Test files
test_ds = test_ds.map(lambda x, y: (x / 255.0, y))
#TRAINING VISUALIZATION
#Count the occurrences of each category in the column
count = df_train['label'].value_counts()
# Create a figure with 2 subplots
fig, axs = plt.subplots(1, 2, figsize=(12, 6), facecolor='white')
# Plot a pie chart on the first subplot
palette = sns.color_palette("viridis")
sns.set_palette(palette)
axs[0].pie(count, labels=count.index, autopct='%1.1f%%', startangle=140)
axs[0].set_title('Distribution of Training Categories')
# Plot a bar chart on the second subplot
sns.barplot(x=count.index, y=count.values, ax=axs[1], palette="viridis")
axs[1].set_title('Count of Training Categories')
# Adjust the layout
plt.tight_layout()
# Visualize
plt.show()
# TEST VISUALIZATION
count = df_test['label'].value_counts()
# Create a figure with 2 subplots
fig, axs = plt.subplots(1, 2, figsize=(12, 6), facec...
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TwitterMany e-shops have started to mark-up product data within their HTML pages using the schema.org vocabulary. The Web Data Commons project regularly extracts such data from the Common Crawl, a large public web crawl. The Web Data Commons Training and Test Sets for Large-Scale Product Matching contain product offers from different e-shops in the form of binary product pairs (with corresponding label “match” or “no match”) for four product categories, computers, cameras, watches and shoes. In order to support the evaluation of machine learning-based matching methods, the data is split into training, validation and test sets. For each product category, we provide training sets in four different sizes (2.000-70.000 pairs). Furthermore there are sets of ids for each training set for a possible validation split (stratified random draw) available. The test set for each product category consists of 1.100 product pairs. The labels of the test sets were manually checked while those of the training sets were derived using shared product identifiers from the Web weak supervision. The data stems from the WDC Product Data Corpus for Large-Scale Product Matching - Version 2.0 which consists of 26 million product offers originating from 79 thousand websites. For more information and download links for the corpus itself, please follow the links below.
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TwitterTrain a machine learning model based on the runtime data provided to you in the training dataset and further predict the runtime of graphs and configurations in the test dataset.
https://www.kaggle.com/code/rishabh15virgo/first-impression-understand-data-eda-baseline-15
https://www.kaggle.com/datasets/rishabh15virgo/google-fast-or-slowtile-xla-train-data-csv-format
https://www.kaggle.com/datasets/rishabh15virgo/google-fast-or-slowtile-xla-test-data-csv-format
Tile .npz files Suppose a .npz file stores a graph (representing a kernel) with n nodes and m edges. In addition, suppose we compile the graph with c different configurations, and run each on a TPU. Crucially, the configuration is at the graph-level. Then, the .npz file stores the following dictionary
Key "node_feat": contains float32 matrix with shape (n, 140). The uth row contains the feature vector for node u < n . Nodes are ordered topologically. Key "node_opcode" contains int32 vector with shape (n, ). The uth entry stores the op-code for node u. Key **"edge_index" **contains int32 matrix with shape (m, 2). If entry i is = u, v, then there is a directed edge from node u to node v, where u consumes the output of v. Key "config_feat" contains float32 matrix with shape (c, 24) with row j containing the (graph-level) configuration feature vector. Keys "config_runtime" and "config_runtime_normalizers": both are int64 vectors of length c. Entry j stores the runtime (in nanoseconds) of the given graph compiled with configuration j and a default configuration, respectively. Samples from the same graph may have slightly different "config_runtime_normalizers" because they are measured from different runs on multiple machines. Finally, for the tile collection, your job is to predict the indices of the best configurations (i.e., ones leading to the smallest d["config_runtime"] / d["config_runtime_normalizers"]).
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Given are the training, test and validation performance as measured by Sensitivity (SE) and Positive Predictive Value (PPV). The training and test performances are computed with a 4-fold cross validation on the training set. In the validation step, iSIS was applied to the entire images for taxa detection and the detection results were compared to our gold standard by computing SE and PPV. The performance decreases significantly from the test data to the validation due to an increase in FP. The last row shows SE and PPV results after a careful re-evaluation of the FP (see text for details) yielding our final estimates for iSIS’ SE and PPV. The last column shows the correlation between object counts of the gold standard items and the machine detection result for the full transect.
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While the traditional viewpoint in machine learning and statistics assumes training and testing samples come from the same population, practice belies this fiction. One strategy—coming from robust statistics and optimization—is thus to build a model robust to distributional perturbations. In this paper, we take a different approach to describe procedures for robust predictive inference, where a model provides uncertainty estimates on its predictions rather than point predictions. We present a method that produces prediction sets (almost exactly) giving the right coverage level for any test distribution in an f-divergence ball around the training population. The method, based on conformal inference, achieves (nearly) valid coverage in finite samples, under only the condition that the training data be exchangeable. An essential component of our methodology is to estimate the amount of expected future data shift and build robustness to it; we develop estimators and prove their consistency for protection and validity of uncertainty estimates under shifts. By experimenting on several large-scale benchmark datasets, including Recht et al.’s CIFAR-v4 and ImageNet-V2 datasets, we provide complementary empirical results that highlight the importance of robust predictive validity.
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TwitterThese are CARLA Simulation Datasets of the project "Out-Of-Domain Data Detection using Uncertainty Quantification in End-to-End Driving Algorithms". The simulations are generated in CARLA Town 02 for different sun angles (in degrees). You will find image frames, command labels, and steering control values in the respective 'xxxx_files_data' folder. You will find videos of each simulation run in the 'xxxx_files_visualizations' folder.
The 8 simulation runs for Training Data, are with the Sun Angles : 90, 80, 70, 60, 50, 40, 30, 20
The 8 simulation runs for Training Data were seeded at 0000, 1000, 2000, 3000, 4000, 5000, 6000, 7000 respectively
The 4 simulation runs for Validation Data, are with the Sun Angles : 87, 67, 47, 23
The 4 simulation runs for Validation Data were seeded at 0000, 2000, 4000, 7000 respectively
The 29 simulation runs for Testing Data, are with the Sun Angles : 85, 75, 65, 55, 45, 35, 25, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 09, 08, 07, 06, 05, 04, 03, 02, 01, 00, -1, -10
The 29 simulation runs for Testing Data were all seeded at 5000 respectively
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TwitterData from the 1/20th wave tank test of the RTI model. Northwest Energy Innovations (NWEI) has licensed intellectual property from RTI, and modified the PTO and retested the 1/20th RTI model that was tested as part of the Wave Energy Prize. The goal of the test was to validate NWEI's simulation models of the model. The test occurred at the University of Maine in Orono (UMO).
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This dataset describes the training, validation and test dataset used for the development of a hybrid ANN coagulation model.
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Twitterhttp://www.gnu.org/licenses/old-licenses/gpl-2.0.en.htmlhttp://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html
The data consist of 45.5K images of dogs and cats well distributed into 3 different sets. This is the first Dataset uploaded by me at Kaggle.
> kaggle datasets download -d kunalgupta2616/dog-vs-cat-images-data
This is an improvement to the dataset from the competition that can be found at this link. in terms of addition of more data and hierarchical distribution.
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Prediction Data of Base Models from Auto-Sklearn 1 on 71 classification datasets from the AutoML Benchmark for Balanced Accuracy and ROC AUC.
The files of this figshare item include data that was collected for the paper:
Q(D)O-ES: Population-based Quality (Diversity) Optimisation for Post Hoc Ensemble Selection in AutoML, Lennart Purucker, Lennart Schneider, Marie Anastacio, Joeran Beel, Bernd Bischl, Holger Hoos, Second International Conference on Automated Machine Learning, 2023.
The data was stored and used with the assembled framework: https://github.com/ISG-Siegen/assembled.
In detail, the data contains the predictions of base models on validation and test as produced by running Auto-Sklearn 1 for 4 hours. Such prediction data is included for each model produced by Auto-Sklearn 1 on each fold of 10-fold cross-validation on the 71 classification datasets from the AutoML Benchmark. The data exists for two metrics (ROC AUC and Balanced Accuracy). More details can be found in the paper.
The data was collected by code created for the paper and is available in its reproducibility repository: https://doi.org/10.6084/m9.figshare.23613624.
Its usage is intended for but not limited to using assembled to evaluate post hoc ensembling methods for AutoML.
Details The link above points to a hosted server that facilitates the download. We opted for a hosted server, as we found no other suitable solution to share these large files (due to file size or storage limits) for a reasonable price. If you want to obtain the data in another way or know of a more suitable alternative, please contact Lennart Purucker.
The link resolves to a directory containing the following:
example_metatasks: contains an example metatask for test purposes before committing to downloading all files.
metatasks_roc_auc.zip: The Metatasks obtained by running Auto-Sklearn 1 for ROC AUC.
metatasks_bacc.zip: The Metatasks obtained by running Auto-Sklearn 1 for Balanced Accuracy.
The size after unzipping the entire file is:
metatasks_roc_auc.zip: ~450GB metatasks_bacc.zip: ~330GB
We suggest extracting only files that are of interest from the .zip archive, as these can be much smaller in size and might suffice for experiments.
The metatask .zip files contain 2 subdirectories for Metatasks produced based on TopN or SiloTopN pruning (see paper for details). In each of these subdirectories, 2 files per metatask exist. One .json file with metadata information and a .hdf or .csv file containing the prediction data. The details on how this should be read and used as a Metatask can be found in the assembled framework and the reproducibility repository. To obtain the data without Metataks, we advise looking at the file content and metadata individually or parsing them by using Metatasks first.
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Research Domain/Project:
This dataset was created for a machine learning experiment aimed at developing a classification model to predict outcomes based on a set of features. The primary research domain is disease prediction in patients. The dataset was used in the context of training, validating, and testing.
Purpose of the Dataset:
The purpose of this dataset is to provide training, validation, and testing data for the development of machine learning models. It includes labeled examples that help train classifiers to recognize patterns in the data and make predictions.
Dataset Creation:
Data preprocessing steps involved cleaning, normalization, and splitting the data into training, validation, and test sets. The data was carefully curated to ensure its quality and relevance to the problem at hand. For any missing values or outliers, appropriate handling techniques were applied (e.g., imputation, removal, etc.).
Structure of the Dataset:
The dataset consists of several files organized into folders by data type:
Training Data: Contains the training dataset used to train the machine learning model.
Validation Data: Used for hyperparameter tuning and model selection.
Test Data: Reserved for final model evaluation.
Each folder contains files with consistent naming conventions for easy navigation, such as train_data.csv, validation_data.csv, and test_data.csv. Each file follows a tabular format with columns representing features and rows representing individual data points.
Software Requirements:
To open and work with this dataset, you need VS Code or Jupyter, which could include tools like:
Python (with libraries such as pandas, numpy, scikit-learn, matplotlib, etc.)
Reusability:
Users of this dataset should be aware that it is designed for machine learning experiments involving classification tasks. The dataset is already split into training, validation, and test subsets. Any model trained with this dataset should be evaluated using the test set to ensure proper validation.
Limitations:
The dataset may not cover all edge cases, and it might have biases depending on the selection of data sources. It's important to consider these limitations when generalizing model results to real-world applications.
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The datasets were used to validate and test the data pipeline deployment following the RADON approach. The dataset has a CSV file that contains around 32000 Twitter tweets. 100 CSV files have been created from the single CSV file and each CSV file containing 320 tweets. Those 100 CSV files are used to validate and test (performance/load testing) the data pipeline components.
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Social scientists often consider multiple empirical models of the same process. When these models are parametric and non-nested, the null hypothesis that two models fit the data equally well is commonly tested using methods introduced by Vuong (Econometrica 57(2):307–333, 1989) and Clarke (Am J Political Sci 45(3):724–744, 2001; J Confl Resolut 47(1):72–93, 2003; Political Anal 15(3):347–363, 2007). The objective of each is to compare the Kullback–Leibler Divergence (KLD) of the two models from the true model that generated the data. Here we show that both of these tests are based upon a biased estimator of the KLD, the individual log-likelihood contributions, and that the Clarke test is not proven to be consistent for the difference in KLDs. As a solution, we derive a test based upon cross- validated log-likelihood contributions, which represent an unbiased KLD estimate. We demonstrate the CVDM test’s superior performance via simulation, then apply it to two empirical examples from political science. We find that the test’s selection can diverge from those of the Vuong and Clarke tests and that this can ultimately lead to differences in substantive conclusions.
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Data and programs for the paper "Nested cross-validation when selecting machine learning algorithms is overzealous"
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Test Data Management Market Size 2025-2029
The test data management market size is forecast to increase by USD 727.3 million, at a CAGR of 10.5% between 2024 and 2029.
The market is experiencing significant growth, driven by the increasing adoption of automation by enterprises to streamline their testing processes. The automation trend is fueled by the growing consumer spending on technological solutions, as businesses seek to improve efficiency and reduce costs. However, the market faces challenges, including the lack of awareness and standardization in test data management practices. This obstacle hinders the effective implementation of test data management solutions, requiring companies to invest in education and training to ensure successful integration. To capitalize on market opportunities and navigate challenges effectively, businesses must stay informed about emerging trends and best practices in test data management. By doing so, they can optimize their testing processes, reduce risks, and enhance overall quality.
What will be the Size of the Test Data Management Market during the forecast period?
Explore in-depth regional segment analysis with market size data - historical 2019-2023 and forecasts 2025-2029 - in the full report.
Request Free SampleThe market continues to evolve, driven by the ever-increasing volume and complexity of data. Data exploration and analysis are at the forefront of this dynamic landscape, with data ethics and governance frameworks ensuring data transparency and integrity. Data masking, cleansing, and validation are crucial components of data management, enabling data warehousing, orchestration, and pipeline development. Data security and privacy remain paramount, with encryption, access control, and anonymization key strategies. Data governance, lineage, and cataloging facilitate data management software automation and reporting. Hybrid data management solutions, including artificial intelligence and machine learning, are transforming data insights and analytics.
Data regulations and compliance are shaping the market, driving the need for data accountability and stewardship. Data visualization, mining, and reporting provide valuable insights, while data quality management, archiving, and backup ensure data availability and recovery. Data modeling, data integrity, and data transformation are essential for data warehousing and data lake implementations. Data management platforms are seamlessly integrated into these evolving patterns, enabling organizations to effectively manage their data assets and gain valuable insights. Data management services, cloud and on-premise, are essential for organizations to adapt to the continuous changes in the market and effectively leverage their data resources.
How is this Test Data Management Industry segmented?
The test data management industry research report provides comprehensive data (region-wise segment analysis), with forecasts and estimates in 'USD million' for the period 2025-2029, as well as historical data from 2019-2023 for the following segments. ApplicationOn-premisesCloud-basedComponentSolutionsServicesEnd-userInformation technologyTelecomBFSIHealthcare and life sciencesOthersSectorLarge enterpriseSMEsGeographyNorth AmericaUSCanadaEuropeFranceGermanyItalyUKAPACAustraliaChinaIndiaJapanRest of World (ROW).
By Application Insights
The on-premises segment is estimated to witness significant growth during the forecast period.In the realm of data management, on-premises testing represents a popular approach for businesses seeking control over their infrastructure and testing process. This approach involves establishing testing facilities within an office or data center, necessitating a dedicated team with the necessary skills. The benefits of on-premises testing extend beyond control, as it enables organizations to upgrade and configure hardware and software at their discretion, providing opportunities for exploration testing. Furthermore, data security is a significant concern for many businesses, and on-premises testing alleviates the risk of compromising sensitive information to third-party companies. Data exploration, a crucial aspect of data analysis, can be carried out more effectively with on-premises testing, ensuring data integrity and security. Data masking, cleansing, and validation are essential data preparation techniques that can be executed efficiently in an on-premises environment. Data warehousing, data pipelines, and data orchestration are integral components of data management, and on-premises testing allows for seamless integration and management of these elements. Data governance frameworks, lineage, catalogs, and metadata are essential for maintaining data transparency and compliance. Data security, encryption, and access control are paramount, and on-premises testing offers greater control over these aspects. Data reporting, visualization, and insigh
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TwitterThis dataset was created by Anna
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Data used to train, validate, and test the VoroIF-GNN method described in the paper "VoroIF-GNN: Voronoi tessellation-derived protein-protein interface assessment using a graph neural network".
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Experimental data obtained from the inspection of steel disks used to validate the UT-SAFT resolution formulas in the referencing paper 'UT-SAFT resolution'. The purpose is to show, that the indication size of small test reflectors matches well with the resolution formulas derived in this paper.
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TwitterThis dataset was an initial test harness infrastructure test for the TrojAI program. It should not be used for research. Please use the more refined datasets generated for the other rounds. The data being generated and disseminated is training, validation, and test data used to construct trojan detection software solutions. This data, generated at NIST, consists of human level AIs trained to perform a variety of tasks (image classification, natural language processing, etc.). A known percentage of these trained AI models have been poisoned with a known trigger which induces incorrect behavior. This data will be used to develop software solutions for detecting which trained AI models have been poisoned via embedded triggers. This dataset consists of 200 trained, human level, image classification AI models using the following architectures (Inception-v3, DenseNet-121, and ResNet50). The models were trained on synthetically created image data of non-real traffic signs superimposed on road background scenes. Half (50%) of the models have been poisoned with an embedded trigger which causes misclassification of the images when the trigger is present.
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Advances in neuroimaging, genomic, motion tracking, eye-tracking and many other technology-based data collection methods have led to a torrent of high dimensional datasets, which commonly have a small number of samples because of the intrinsic high cost of data collection involving human participants. High dimensional data with a small number of samples is of critical importance for identifying biomarkers and conducting feasibility and pilot work, however it can lead to biased machine learning (ML) performance estimates. Our review of studies which have applied ML to predict autistic from non-autistic individuals showed that small sample size is associated with higher reported classification accuracy. Thus, we have investigated whether this bias could be caused by the use of validation methods which do not sufficiently control overfitting. Our simulations show that K-fold Cross-Validation (CV) produces strongly biased performance estimates with small sample sizes, and the bias is still evident with sample size of 1000. Nested CV and train/test split approaches produce robust and unbiased performance estimates regardless of sample size. We also show that feature selection if performed on pooled training and testing data is contributing to bias considerably more than parameter tuning. In addition, the contribution to bias by data dimensionality, hyper-parameter space and number of CV folds was explored, and validation methods were compared with discriminable data. The results suggest how to design robust testing methodologies when working with small datasets and how to interpret the results of other studies based on what validation method was used.