Mathematics · Statistics
Random-Effects Meta-Analysis Total Variance Calculator
Calculate random-effects total variance from study within-sampling variance and between-study variance tau squared.
Inputs and results stay in this browser. Change one value at a time to explore the relationship.
Calculation steps
- Use c=a+b with study within-sampling variance=0.04 and between-study variance tau squared=0.018.
- random-effects total variance=0.057999999999999996.
Understand Random-Effects Meta-Analysis Total Variance
One idea, three depths
Choose how deeply to explain Random-Effects Meta-Analysis Total Variance
Random-Effects Meta-Analysis Total Variance: Calculate random-effects total variance from study within-sampling variance and between-study variance tau squared.
Age 5Explain it to a 5-year-oldStart with a picture
Imagine using Random-Effects Meta-Analysis Total Variance to answer this question: calculate random-effects total variance from study within-sampling variance and between-study variance tau squared? Enter study within-sampling variance and between-study variance tau squared; the calculator shows random-effects total variance. For example: study within-sampling variance=0.04 and between-study variance tau squared=0.018 produce random-effects total variance=0.057999999999999996. The answer tells you random-effects total variance.
Age 15Explain it to a 15-year-oldConnect it to the formula
A conventional random-effects weight uses within-study sampling variance plus estimated between-study variance. This page evaluates the relationship directly. The rule is c=a+b. Its input values are study within-sampling variance, between-study variance tau squared, and the main result is random-effects total variance. For example: study within-sampling variance=0.04 and between-study variance tau squared=0.018 produce random-effects total variance=0.057999999999999996.
CollegeExplain it at college levelState the model precisely
This calculator evaluates the stated random-effects meta-analysis total variance relation over the valid real-number domain stated below. The implemented relation is c=a+b, evaluated from study within-sampling variance, between-study variance tau squared to produce random-effects total variance. A conventional random-effects weight uses within-study sampling variance plus estimated between-study variance. This page evaluates the relationship directly. The estimator used for tau squared should be reported.
Inputs and valid domain
- study within-sampling variance must be a finite real number.
- between-study variance tau squared must be a finite real number.
Important boundary: The estimator used for tau squared should be reported.
The formula
c=a+b
How the calculator works through it
It substitutes study within-sampling variance, between-study variance tau squared into the formula and exposes every numerical step above. The main output is random-effects total variance.
Read the result correctly
The random-effects total variance is the direct answer to “calculate random-effects total variance from study within-sampling variance and between-study variance tau squared.” Read it with the units shown beside the inputs; a sign, angle, percentage or rate changes what the number means.
A worked check
study within-sampling variance=0.04 and between-study variance tau squared=0.018 produce random-effects total variance=0.057999999999999996.
Where this model stops being reliable
The estimator used for tau squared should be reported.
Learn it by changing one value
Begin with the worked example, then change one value while keeping the others fixed. Compare the new result and calculation steps to identify which part of the formula changed.
Dictionary terms behind this calculator
Before studying the codeWhat you should know firstUse the calculator immediately, or check the foundations before reading the implementation.
These foundations help you understand why Random-Effects Meta-Analysis Total Variance works. They never block the calculator, and “optional” means useful context rather than a hidden requirement.
Hard requirements
- Reading formulas and substituting values
Random-Effects Meta-Analysis Total Variance uses c=a+b. You need to recognise what each side represents before substituting the stated inputs or rearranging the relationship.
Review this foundation about 4 min
Strong support
- Averages and representative values
Representative values help you judge what the Random-Effects Meta-Analysis Total Variance inputs summarise and what the result can legitimately describe.
Review this foundation about 5 min
Optional enrichment
- Spread and measurement variation
Variation is not always part of the Random-Effects Meta-Analysis Total Variance formula, but it helps you judge how stable a reported result may be.
Review this foundation about 6 min
Mathematics → algorithm → program
Implement this calculation in code
These are direct reference implementations of the calculator's principal relationship and first output. They run locally and include a small known-answer check where the language supports it.
Algorithm
- Read study within-sampling variance, between-study variance tau squared.
- Evaluate the principal relationship: c=a+b.
- Return random-effects total variance and check the domain conditions described above.
Python
from math import *
def random_effects_total_variance_calculator(a, b) -> float:
return (a + b)
assert abs(random_effects_total_variance_calculator(0.04, 0.018) - 0.057999999999999996) < 1e-6 * max(1.0, abs(0.057999999999999996))
C
#include <assert.h>
#include <math.h>
double random_effects_total_variance_calculator(double a, double b) {
return (a + b);
}
int main(void) {
const double expected = 0.057999999999999996;
const double actual = random_effects_total_variance_calculator(0.04, 0.018);
assert(fabs(actual - expected) < 1e-6 * fmax(1.0, fabs(expected)));
}
C++
#include <cassert>
#include <cmath>
#include <numbers>
double random_effects_total_variance_calculator(double a, double b) {
return (a + b);
}
int main() {
constexpr double expected = 0.057999999999999996;
const double actual = random_effects_total_variance_calculator(0.04, 0.018);
assert(std::fabs(actual - expected) < 1e-6 * std::fmax(1.0, std::fabs(expected)));
}
Linux x86-64 assembly
x86-64 NASM · System V ABI · Linux · SSE2 with libm where required
; double random_effects_total_variance_calculator(double a, double b)
; Linux x86-64 NASM · System V ABI · first eight doubles in xmm0–xmm7
global random_effects_total_variance_calculator
section .text
random_effects_total_variance_calculator:
push rbp
mov rbp, rsp
sub rsp, 32
movsd [rbp-8], xmm0
movsd [rbp-16], xmm1
movsd xmm0, [rbp-8]
addsd xmm0, [rbp-16]
movsd [rbp-24], xmm0
movsd xmm0, [rbp-24]
leave
ret
MATLAB
function result = random_effects_total_variance_calculator(a, b)
result = (a + b);
end
Wolfram Language
ClearAll[mwCalculate];
mwCalculate[a_, b_] := (a + b);
Continue in mathematical software
The downloaded file includes your current inputs and first calculated result. It is created locally.
Floating-point answers can differ slightly by language, compiler and processor. Compare within a suitable tolerance rather than assuming every decimal representation will be identical.
Supporting sourcesAcademic referencesPrimary standards, textbooks and complete citations
Standards, reading and academic references
Use the calculator as the worked interaction, then consult the primary standards and academic textbooks listed below. MW SysArc links to the original sources; the explanation on this page is original and does not reproduce them.
Introductory Statistics 2e
Read the free OpenStax statistics textbookCite this book
- APA 7
- Illowsky, B., & Dean, S. (2023). Introductory statistics 2e. OpenStax. https://openstax.org/books/introductory-statistics-2e/pages/1-introduction
- MLA 9
- Illowsky, Barbara, and Susan Dean. Introductory Statistics 2e. OpenStax, 2023, https://openstax.org/books/introductory-statistics-2e/pages/1-introduction.
- Chicago author-date
- Illowsky, Barbara, and Susan Dean. 2023. Introductory Statistics 2e. Houston, TX: OpenStax. https://openstax.org/books/introductory-statistics-2e/pages/1-introduction.
OpenStax entries are free to read online. Follow the licence shown on each linked source before redistributing or adapting its content.
Reuse the page responsiblyCite this pageAPA, MLA, Chicago, Harvard, BibTeX and RIS
These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.
APA 7
MW SysArc. (2026, July 21). Random-Effects Meta-Analysis Total Variance Calculator. MW SysArc Tools. https://math.mwsysarc.com/statistics/random-effects-total-variance-calculator
MLA 9
MW SysArc. “Random-Effects Meta-Analysis Total Variance Calculator.” MW SysArc Tools, 21 July 2026, https://math.mwsysarc.com/statistics/random-effects-total-variance-calculator. Accessed 31 Aug. 2026.
Chicago 17
MW SysArc. “Random-Effects Meta-Analysis Total Variance Calculator.” MW SysArc Tools. Published July 21, 2026. Accessed August 31, 2026. https://math.mwsysarc.com/statistics/random-effects-total-variance-calculator.
Harvard
MW SysArc (2026) ‘Random-Effects Meta-Analysis Total Variance Calculator’, MW SysArc Tools. Published 21 July 2026. Available at: https://math.mwsysarc.com/statistics/random-effects-total-variance-calculator (Accessed: 31 August 2026).
BibTeX and RIS records
BibTeX
@misc{mwsysarc_random_effects_total_variance_calculator_2026,
author = {{MW SysArc}},
title = {Random-Effects Meta-Analysis Total Variance Calculator},
howpublished = {MW SysArc Tools},
year = {2026},
url = {https://math.mwsysarc.com/statistics/random-effects-total-variance-calculator},
note = {Published July 21, 2026; accessed August 31, 2026}
}RIS
TY - ELEC
AU - MW SysArc
TI - Random-Effects Meta-Analysis Total Variance Calculator
T2 - MW SysArc Tools
PY - 2026
DA - 2026-07-21
Y2 - 2026-08-31
UR - https://math.mwsysarc.com/statistics/random-effects-total-variance-calculator
N1 - Published July 21, 2026
ER -Clear answers
Frequently asked questions
What does the Random-Effects Meta-Analysis Total Variance do?
Calculate random-effects total variance from study within-sampling variance and between-study variance tau squared.
How does the Random-Effects Meta-Analysis Total Variance work?
The calculator applies c=a+b. A conventional random-effects weight uses within-study sampling variance plus estimated between-study variance. This page evaluates the relationship directly.
What can I learn from the Random-Effects Meta-Analysis Total Variance?
It connects the mathematical rule to your chosen numbers and shows each calculation step. Change one input at a time to see how the result responds.
Does MW SysArc receive or store what I enter?
No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.
How should I use the result?
Use the steps to understand the method, then verify important school or professional work using the notation and rounding rules required in your setting.
Last reviewed . Calculations tested .