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\section*{Background}  Dust devils are small-scale (few to many tens of meters) low-pressure vortices rendered visible by lofted dust. They usually occur in arid climates on the Earth and ubiquitously on Mars, where they may dominate the supply of atmospheric dust and influence climate. Mars.  Martian dust devils have been studied with orbiting and landed spacecraft and were first identified on Mars using images from the Viking Orbiter \citep{Thomas_1985}. On Mars, dust devils may dominate the supply of atmospheric dust and influence climate \cite{Basu_2004}, pose a hazard for human exploration \citep{Balme_2006}, and have lengthened the operational lifetime of Martian rovers (http://mars.jpl.nasa.gov/mer/mission/status_opportunityAll.html#sol3603). On  the Earth, dust devils may help significantly  degrade air quality in arid climates \citep{Gillette_1990} andmay  pose an aviation hazard \cite{Lorenz_2005}.  The dust-lifting capacity of dust devils seems to depend sensitively on their structures, in particular on the pressure wells at their centers \citep{Neakrase_2006}, so the dust supply from dust devils on both planets may be dominated by the seldom observed larger devils. Thus, it is particularly important to study the underlying distribution of dust devil properties. Thus, elucidating the origin, evolution, and population statistics of dust devils is critical for understanding important terrestrial and Martian atmospheric properties and for in-situ exploration of Mars -- dust devils might pose a hazard for human exploration \citep{Balme_2006} but have also apparently lengthened the operational lifetime of Martian rovers (http://mars.jpl.nasa.gov/mer/mission/status_opportunityAll.html#sol3603). Mars.  Studies of Martian dust devils have been conducted either through direct imaging of the devils, identification of their tracks on Mars' dusty surface \citep[cf.][]{Balme_2006}. Studies with in-situ meteorological instrumentation have also identified dust devils,either via obscuration of the Sun by the dust column \citep{Zorzano_2013} or their pressure signals \citep{Ellehoj_2010}. Studies of terrestrial dust devils frequently involve in-person monitoring of field sites, and dust devils are visually surveyed \citep{Pathare_2010} or directly sampled \citep{Balme_2003}. There is a long history of terrestrial dust devil studies using in-situ meteorological equipment as well \cite{Sinclair_1973, Lorenz_2012}.  A long series of subsequent dust devil studies have followed, either through direct imaging or by identification of their tracks on Mars' dusty surface \citep[cf.][]{Balme_2006}. Meteorological sensors have also provided evidence for Martian dust devils passing near landed craft, either via obscuration of the Sun by the dust column \citep{Zorzano_2013} or their pressure signals \citep{Ellehoj_2010}.   Studies of terrestrial Terrestrial  dust devils frequently involve in-person monitoring devil surveys using in-situ sensors have the advantage  of field sites, being directly analogous to Martian surveys  anddust devils  are visually surveyed \citep{Pathare_2010} or directly sampled \citep{Balme_2003}. highly cost-effective compared to the in-person surveys.  As noted in \citet{Lorenz_2009}, in-person visual surveys are likely to be biased toward detection of larger, more easily seen devils. Such surveys would also fail to recover dustless vortices \citep{Lorenz_2015}. Recently, terrestrial t Terrestrial  surveys similar to Martian dust devil surveys have been conducted using in-situ single barometers \citep{Lorenz_2012, Lorenz_2014, Jackson_2015} and photovoltaic sensors \citep{Lorenz_2015}. These sensor-based terrestrial surveys have the advantage of being directly analogous to Martian surveys and are highly cost-effective compared to the in-person surveys. In this kind of single-barometer survey, a sensor is deployed in-situ record a pressure time series at a sampling rate $\lesssim 1$ s. As a low-pressure convective vortex, the nearby passage of a dust devil will register as pressure dip discernible against a background ambient (but not necessarily constant) pressure. Figure \ref{fig:conditioning_detection_b_inset} from \citet{Jackson_2015} shows a time-series with a typical dust devil signal. However, as with visual surveys, single-sensor barometer surveys suffer from biases as well, primarily from the ``miss distance'' effect: a fixed barometric sensor is more likely to have a more distant than closer encounter with a dust devil. Since the pressure perturbation associated with a devil falls off with distance, the deepest point in the observed pressure profile will almost always be less than the actual pressure well at the devil's center. The observed shape of the profile will be distorted as well. These biases are intrinsic to the detection methods, and additional biases can influence the inferred statistical properties. For instance, noise in the pressure time series from a barometer may make more difficult detection of a dust devils with smaller pressure perturbations, depending on the exact detection scheme.  The plan of this paper is as follow: In Section \ref{sec:miss_distance_effect}, we discuss the influence of the miss distance effect on the observed parameters for dust devil profiles and on their distributions. In