# Estimating Spatial Averages of Environmental Parameters based on Mobile Crowdsensing

### Ioannis Koukoutsidis

#### Abstract

Mobile crowdsensing can facilitate environmental surveys by leveraging sensor-equipped mobile devices that carry out measurements covering a wide area in a short time, without bearing the costs of traditional field work. In this paper, we examine statistical methods to perform an accurate estimate of the mean value of an environmental parameter in a region, based on such measurements. The main focus is on estimates produced by considering the mobile device readings at a random instant in time. We compare stratified sampling with different stratification weights to sampling without stratification, as well as an appropriately modified version of systematic sampling. Our main result is that stratification with weights proportional to stratum areas can produce significantly smaller bias, and gets arbitrarily close to the true area average as the number of mobiles increases, for a moderate number of strata. The performance of the methods is evaluated for an application scenario where we estimate the mean area temperature in a linear region that exhibits the so-called Urban Heat Island effect, with mobile users moving in the region according to the Random Waypoint Model.

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#### Paper Citation

#### in Harvard Style

Koukoutsidis I. (2017). **Estimating Spatial Averages of Environmental Parameters based on Mobile Crowdsensing** . In *Proceedings of the 6th International Conference on Sensor Networks - Volume 1: SENSORNETS,* ISBN 978-989-758-211-0, pages 15-26. DOI: 10.5220/0006110900150026

#### in Bibtex Style

@conference{sensornets17,

author={Ioannis Koukoutsidis},

title={Estimating Spatial Averages of Environmental Parameters based on Mobile Crowdsensing},

booktitle={Proceedings of the 6th International Conference on Sensor Networks - Volume 1: SENSORNETS,},

year={2017},

pages={15-26},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0006110900150026},

isbn={978-989-758-211-0},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 6th International Conference on Sensor Networks - Volume 1: SENSORNETS,

TI - Estimating Spatial Averages of Environmental Parameters based on Mobile Crowdsensing

SN - 978-989-758-211-0

AU - Koukoutsidis I.

PY - 2017

SP - 15

EP - 26

DO - 10.5220/0006110900150026