# Confidence Intervals for Sobol Global Sensitivity Analysis

**URL:** https://discourse.julialang.org/t/confidence-intervals-for-sobol-global-sensitivity-analysis/113671
**Category:** Modelling & Simulations
**Created:** [April 30, 2024, 9:44pm UTC](https://discourse.julialang.org/t/confidence-intervals-for-sobol-global-sensitivity-analysis/113671 "2024-04-30T21:44:50Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![Nick1](https://avatars.discourse-cdn.com/v4/letter/n/47e85d/32.png) [@Nick1](https://discourse.julialang.org/u/Nick1)
#### Post date: [April 30, 2024, 9:44pm UTC](https://discourse.julialang.org/t/confidence-intervals-for-sobol-global-sensitivity-analysis/113671/1 "2024-04-30T21:44:50Z")

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I was running the example for Sobol sensitivity analysis, which was mentioned in the tutorial ([Sobol Method · GlobalSensitivity.jl](https://docs.sciml.ai/GlobalSensitivity/v1.2/methods/sobol/)) and I observed that when I specified the **nboot** argument to calculate the confidence intervals, it returns nothing. I use the GlobalSensitivity v2.5.0.

Thank you!

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### Author: ![ChrisRackauckas](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/chrisrackauckas/32/77_2.png) [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)
#### Post date: [May 1, 2024, 12:49pm UTC](https://discourse.julialang.org/t/confidence-intervals-for-sobol-global-sensitivity-analysis/113671/2 "2024-05-01T12:49:22Z")

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@Vaibhavdixit02 can you look at this?

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### Author: ![Vaibhavdixit02](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/vaibhavdixit02/32/2916_2.png) [@Vaibhavdixit02](https://discourse.julialang.org/u/Vaibhavdixit02)
#### Post date: [May 1, 2024, 9:22pm UTC](https://discourse.julialang.org/t/confidence-intervals-for-sobol-global-sensitivity-analysis/113671/3 "2024-05-01T21:22:26Z")

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Can you show the code you ran and the outpu @Nick1

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<div class="post-metadata">

### Author: ![Nick1](https://avatars.discourse-cdn.com/v4/letter/n/47e85d/32.png) [@Nick1](https://discourse.julialang.org/u/Nick1)
#### Post date: [May 13, 2024, 6:32pm UTC](https://discourse.julialang.org/t/confidence-intervals-for-sobol-global-sensitivity-analysis/113671/4 "2024-05-13T18:32:20Z")

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The code I am using is this one:

```julia

using GlobalSensitivity, QuasiMonteCarlo

function ishi(X)
    A= 7
    B= 0.1
    sin(X[1]) + A*sin(X[2])^2+ B*X[3]^4 *sin(X[1])
end

samples = 600000
lb = -ones(4)*π
ub = ones(4)*π
sampler = SobolSample()
A,B = QuasiMonteCarlo.generate_design_matrices(samples,lb,ub,sampler)

res1 = gsa(ishi,Sobol(order=[0,1,2]),nboot = 100,A,B)

function ishi_batch(X)
    A= 7
    B= 0.1
    @. sin(X[1,:]) + A*sin(X[2,:])^2+ B*X[3,:]^4 *sin(X[1,:])
end

res2 = gsa(ishi_batch,Sobol(order=[0,1,2]),nboot = 100, A,B,batch=true)

```

The code is from this link:

> **[Sobol Method · GlobalSensitivity.jl](https://docs.sciml.ai/GlobalSensitivity/stable/methods/sobol/)**
>
> Documentation for GlobalSensitivity.jl.