From bb8346f2d6714c85b5a545bb1d3011a6155ccfd9 Mon Sep 17 00:00:00 2001 From: katerinatzo Date: Thu, 14 Oct 2021 16:15:32 +0200 Subject: [PATCH] working on 4.1 --- text/problem/thething/main.tex | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/text/problem/thething/main.tex b/text/problem/thething/main.tex index 4584ad4..fe60e98 100644 --- a/text/problem/thething/main.tex +++ b/text/problem/thething/main.tex @@ -1,17 +1,19 @@ \section{Significant events} \label{sec:thething} -The privacy mechanisms for the aforementioned levels assume that in a time series any single event, or any sequence of events, or the entire series of events is equally privacy-significant for the users. -In reality, this is an simplistic assumption. -The significance of an event is related to certain user-defined privacy criteria, or to its adjacent events, as well as to the entire time series. -We term significant events as \emph{{\thething} events} or simply \emph{\thethings}. -Identifying {\thethings} can be done in an automatic or manual way (but is out of scope for this work). +The privacy mechanisms for the user, w-event and event levels that are already proposed in the literature, assume that in a time series any single event, or any sequence of events, or the entire series of events is equally privacy-significant for the users. +In reality, this is a simplistic\kat{I would not say simplistic, but unrealistic assumption that deteriorates unnecessarily the quality of the perturbed data} assumption. +The fact that an event is significant, can be related to certain user-defined privacy criteria, or to its adjacent events, as well as to the entire time series. +We term significant events as \emph{{\thething} events} or simply \emph{\thethings}, following relevant literature\kat{can you find some other work that uses the same term? otherwise one can raise the question why not ot use the word significant }. + +Identifying {\thethings} in timeseries can be done in an automatic or manual way. For example, in spatiotemporal data, \emph{places where an individual spent some time} denote \emph{points of interest} (POIs) (called also stay points)~\cite{zheng2015trajectory}. Such events, and more particularly their spatial attribute values, can be less privacy-sensitive~\cite{primault2018long}, e.g.,~parks, theaters, etc. or, if individuals frequent them, they can reveal supplementary information, e.g.,~residences (home addresses)~\cite{gambs2010show}, places of worship (religious beliefs)~\cite{franceschi-bicchierairussell2015redditor}, etc. POIs can be an example of how we can choose {\thethings}, but the idea is not limited to these. Another example is the detection of privacy-sensitive user interactions by \emph{contact tracing} applications. This can be practical in decease control~\cite{eames2003contact}, similar to the recent outbreak of the Coronavirus disease 2019 (COVID-19) epidemic~\cite{ahmed2020survey}. Last but not least, {\thethings} in \emph{smart grid} electricity usage patterns could not only reveal the energy consumption of a user but also information regarding activities, e.g.,~`at work', `sleeping', etc. and types of appliances already installed or recently purchased~\cite{khurana2010smart}. +We stress out that {\thething} identification is an orthogonal problem to ours, and that we consider {\thethings} given as input to our problem. \begin{example} \label{ex:st-cont}