Principal component analysisPrincipal component analysis (PCA) is a popular technique for analyzing large datasets containing a high number of dimensions/features per observation, increasing the interpretability of data while preserving the maximum amount of information, and enabling the visualization of multidimensional data. Formally, PCA is a statistical technique for reducing the dimensionality of a dataset. This is accomplished by linearly transforming the data into a new coordinate system where (most of) the variation in the data can be described with fewer dimensions than the initial data.
SurveillanceSurveillance is the monitoring of behavior, many activities, or information for the purpose of information gathering, influencing, managing or directing. This can include observation from a distance by means of electronic equipment, such as closed-circuit television (CCTV), or interception of electronically transmitted information like Internet traffic. It can also include simple technical methods, such as human intelligence gathering and postal interception. Surveillance is used by citizens for protecting their neighborhoods.
IPod TouchThe iPod Touch (stylized as iPod touch) is a discontinued line of iOS-based mobile devices designed and marketed by Apple Inc. with a touchscreen-controlled user interface. As with other iPod models, the iPod Touch can be used as a portable media player and a handheld gaming device, but can also be used as a digital camera, a web browser, for email and messaging. It is nearly identical in design to the iPhone, and can run most iPhone third-party apps from the App Store, but it connects to the internet only through Wi-Fi and uses no cellular network data since it lacks a cellular modem.
IPadThe iPad is a brand of iOS and iPadOS-based tablet computers that are developed by Apple Inc, first introduced on January 27, 2010. The iPad range consists of the original iPad lineup and the flagship products iPad Mini, iPad Air, and iPad Pro. The iPhone's iOS operating system (OS) was initially used for the iPad but in September 2019, its OS was switched to a fork of iOS called iPadOS that has better support for the device's hardware and its user interface is customized for the tablets' larger screens.