Jove
Visualize
Contact Us

Related Concept Videos

One-Compartment Open Model: Wagner-Nelson and Loo Riegelman Method for ka Estimation01:24

One-Compartment Open Model: Wagner-Nelson and Loo Riegelman Method for ka Estimation

This lesson introduces two critical methods in pharmacokinetics, the Wagner-Nelson and Loo-Riegelman methods, used for estimating the absorption rate constant (ka) for drugs administered via non-intravenous routes. The Wagner-Nelson method relates ka to the plasma concentration derived from the slope of a semilog percent unabsorbed time plot. However, it is limited to drugs with one-compartment kinetics and can be impacted by factors like gastrointestinal motility or enzymatic degradation.
On...
Kruskal-Wallis Test01:19

Kruskal-Wallis Test

The Kruskal-Wallis test, also known as the Kruskal-Wallis H test, serves as a nonparametric alternative to the one-way ANOVA, offering a solution for analyzing the differences across three or more independent groups based on a single, ordinal-dependent variable. This statistical test is particularly valuable in scenarios where the data does not meet the normal distribution assumption required by its parametric counterparts. Kruskal-Wallis test is designed typically to handle ordinal data or...
Random Error01:04

Random Error

Random or indeterminate errors originate from various uncontrollable variables, such as variations in environmental conditions, instrument imperfections, or the inherent variability of the phenomena being measured. Usually, these errors cannot be predicted, estimated, or characterized because their direction and magnitude often vary in magnitude and direction even during consecutive measurements. As a result, they are difficult to eliminate. However, the aggregate effect of these errors can be...
One-Way ANOVA: Unequal Sample Sizes01:15

One-Way ANOVA: Unequal Sample Sizes

One-way ANOVA can be performed on three or more samples of unequal sizes. However, calculations get complicated when sample sizes are not always the same. So, while performing ANOVA with unequal samples size, the following equation is used:
One-Way ANOVA: Equal Sample Sizes01:15

One-Way ANOVA: Equal Sample Sizes

One-Way ANOVA can be performed on three or more samples with equal or unequal sample sizes. When one-way ANOVA is performed on two datasets with samples of equal sizes, it can be easily observed that the computed F statistic is highly sensitive to the sample mean.
Different sample means can result in different values for the variance estimate: variance between samples. This is because the variance between samples is calculated as the product of the sample size and the variance between the...
Uncertainty in Measurement: Accuracy and Precision03:37

Uncertainty in Measurement: Accuracy and Precision

Scientists typically make repeated measurements of a quantity to ensure the quality of their findings and to evaluate both the precision and the accuracy of their results. Measurements are said to be precise if they yield very similar results when repeated in the same manner. A measurement is considered accurate if it yields a result that is very close to the true or the accepted value. Precise values agree with each other; accurate values agree with a true value.

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

The Effects of Aspartame, Sucrose, and Water on Short-Term Cognitive Performance.

Perceptual and motor skills·2026
Same author

The effects of alternate-day fasting on sleep and physical activity in poor sleeping adults: A randomized control trial.

Journal of sleep research·2024
Same author

COVID-19 hotspot detection in a university setting.

PloS one·2024
Same author

The Effects of Potato Presentation on Vegetable Intake in School-Aged Children: A Cross-Over Study.

Nutrients·2023
Same author

Body shape perception in men and women without obesity during caloric restriction: a secondary analysis from the CALERIE study.

Eating and weight disorders : EWD·2023
Same author

Distributional Validation of Precipitation Data Products with Spatially Varying Mixture Models.

Journal of agricultural, biological, and environmental statistics·2023
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Video

Updated: Jun 4, 2026

Measurement of Spatial Stability in Precision Grip
09:36

Measurement of Spatial Stability in Precision Grip

Published on: June 4, 2020

Filtered kriging for spatial data with heterogeneous measurement error variances.

William F Christensen1

  • 1Department of Statistics, Brigham Young University, Provo, Utah 84602, USA. william@stat.byu.edu

Biometrics
|March 3, 2011
PubMed
Summary

This study introduces a new kriging method to accurately predict spatial processes with varying measurement errors. The heterogeneous variance-filtered kriging (HFK) method improves predictions by accounting for site-specific error variances.

More Related Videos

Sampling Soils in a Heterogeneous Research Plot
07:11

Sampling Soils in a Heterogeneous Research Plot

Published on: January 7, 2019

Related Experiment Videos

Last Updated: Jun 4, 2026

Measurement of Spatial Stability in Precision Grip
09:36

Measurement of Spatial Stability in Precision Grip

Published on: June 4, 2020

Sampling Soils in a Heterogeneous Research Plot
07:11

Sampling Soils in a Heterogeneous Research Plot

Published on: January 7, 2019

Area of Science:

  • Geostatistics
  • Spatial Statistics
  • Environmental Science

Background:

  • Standard spatial prediction assumes uniform measurement error variance.
  • Real-world spatial data often exhibits site-specific, heterogeneous measurement error variances, leading to nonstationary observed processes.
  • This heterogeneity complicates accurate prediction of the underlying, error-free spatial process.

Purpose of the Study:

  • To develop a novel kriging predictor that effectively filters measurement errors in spatial data with heterogeneous variances.
  • To propose methods for estimating the semivariogram of the unobservable, error-free spatial process.
  • To demonstrate the improved performance of the new methods compared to standard approaches.

Main Methods:

  • Developed a bias-adjusted semivariogram estimation for the error-free process.
  • Introduced a heterogeneous variance-filtered kriging (HFK) predictor.
  • Recommended a variance-stabilizing transformation for cases where error variance depends on the process.
  • Validated methods through simulation studies and application to climate model data.

Main Results:

  • The HFK predictor and its variance-stabilized variant effectively filter measurement errors.
  • These new methods show significant improvement over standard measurement-error-filtered kriging.
  • Simulations confirmed the properties and advantages of the proposed HFK predictors.
  • Application to climate data demonstrated appropriate down/up-weighting of sites based on error variance.

Conclusions:

  • The proposed HFK approach provides a robust solution for spatial prediction with heterogeneous measurement errors.
  • Accounting for site-specific error variances leads to more realistic and accurate predictions of the underlying spatial process.
  • The methods offer a valuable tool for analyzing spatial data in fields like environmental science and climate modeling.