相关实验视频
Updated: Jul 17, 2025

13:19
Deep Neural Networks for Image-Based Dietary Assessment
Published on: March 13, 2021
9.2K
更深的总是更好吗? 评估深度学习模型以小数据进行收益预测.
Filip Sabo1, Michele Meroni2, François Waldner2
1European Commission, Joint Research Centre, Ispra, Italy. filip.szabo@ec.europa.eu.
Environmental monitoring and assessment
|September 6, 2023
概括
深度学习模型难以准确预测作物产量,即使使用卫星数据. 传统的基准和机器学习的表现优于深度学习,原因是数据集大小有限,突出了数据数量.
科学领域:
- 农业科学 农业科学
- 数据科学数据科学数据科学
- 机器学习 机器学习
背景情况:
- 准确的作物产量预测对于粮食安全至关重要,特别是在脆弱的国家.
- 预测异常低收益率需要强大而适应的建模技术.
- 卫星数据提供了一个全球可访问的资源,用于近乎实时的农业监测.
研究的目的:
- 研究一个灵活的深度学习方法,用于省级农作物产量预测.
- 以有限的数据来评估1D和2D卷积神经网络 (CNN) 的性能.
- 将深度学习模型与传统基准和机器学习算法进行比较.
主要方法:
- 利用深度1D和2DCNN与超参数优化进行模型选择.
- 输入数据包括规范差异植被指数 (NDVI) 的3D直方图和二维CNN的气候数据.
- 采用NDVI和气候数据的时间序列平均值1D CNN,应用于阿尔及利亚作物数据 (2002-2018).
主要成果:
- 与传统的基准和机器学习算法相比,深度学习模型表现不佳.
- 像峰值NDVI这样的简单基准很难超越.
- 机器学习模型在所有作物和预测月份的深度学习中始终表现出色.
结论:
- 现有数据集的有限规模被确定为深度学习模型性能差的主要原因.
- 开发的深度学习方法虽然灵活且可转移,但需要更大的数据集才能有效地预测产量.
- 进一步的研究应该集中在数据增强或转移学习策略上,以提高使用稀疏数据的深度学习有效性.
相关概念视频
Survival Tree
109
Survival trees are a non-parametric method used in survival analysis to model the relationship between a set of covariates and the time until an event of interest occurs, often referred to as the "time-to-event" or "survival time." This method is particularly useful when dealing with censored data, where the event has not occurred for some individuals by the end of the study period, or when the exact time of the event is unknown.
Building a Survival Tree
Constructing a...
Building a Survival Tree
Constructing a...
109
Prediction Intervals
2.3K
The interval estimate of any variable is known as the prediction interval. It helps decide if a point estimate is dependable.
However, the point estimate is most likely not the exact value of the population parameter, but close to it. After calculating point estimates, we construct interval estimates, called confidence intervals or prediction intervals. This prediction interval comprises a range of values unlike the point estimate and is a better predictor of the observed sample value, y.
However, the point estimate is most likely not the exact value of the population parameter, but close to it. After calculating point estimates, we construct interval estimates, called confidence intervals or prediction intervals. This prediction interval comprises a range of values unlike the point estimate and is a better predictor of the observed sample value, y.
2.3K
Regression Analysis
5.8K
Regression analysis is a statistical tool that describes a mathematical relationship between a dependent variable and one or more independent variables.
In regression analysis, a regression equation is determined based on the line of best fit– a line that best fits the data points plotted in a graph. This line is also called the regression line. The algebraic equation for the regression line is called the regression equation. It is represented as:
In regression analysis, a regression equation is determined based on the line of best fit– a line that best fits the data points plotted in a graph. This line is also called the regression line. The algebraic equation for the regression line is called the regression equation. It is represented as:
5.8K
Improving Translational Accuracy
11.6K
Base complementarity between the three base pairs of mRNA codon and the tRNA anticodon is not a failsafe mechanism. Inaccuracies can range from a single mismatch to no correct base pairing at all. The free energy difference between the correct and nearly correct base pairs can be as small as 3 kcal/ mol. With complementarity being the only proofreading step, the estimated error frequency would be one wrong amino acid in every 100 amino acids incorporated. However, error frequencies observed in...
11.6K
Estimating Population Standard Deviation
3.0K
When the population standard deviation is unknown and the sample size is large, the sample standard deviation s is commonly used as a point estimate of σ. However, it can sometimes under or overestimate the population standard deviation. To overcome this drawback, confidence intervals are determined to estimate population parameters and eliminate any calculation bias accurately. However, this only applies to random samples from normally distributed populations. Knowing the sample mean and...
3.0K
Regression Toward the Mean
6.3K
Regression toward the mean (“RTM”) is a phenomenon in which extremely high or low values—for example, and individual’s blood pressure at a particular moment—appear closer to a group’s average upon remeasuring. Although this statistical peculiarity is the result of random error and chance, it has been problematic across various medical, scientific, financial and psychological applications. In particular, RTM, if not taken into account, can interfere when...
6.3K

