many studies have been connected using Bluetooth beacons for tracking. A few methods have been tested to find the best way of combining the RSSI values for tracking. Neural networks have been proposed as a good way of reducing the error in estimation. A Stigmergic approach has also been tested, this method uses an intensity map to estimate a users location. Bluetooth LE specification 5.1 added further more precise methods for position determination using multiple beacons. One beacon per room With only one beacon per room, a user can use their known room position in conjunction with a virtual map of all the rooms in a building to navigate a building. A building with many separate rooms may need a different beacon configuration for navigation. With one beacon in each room a user can use an app to know the room they are in, and a simple shortest path algorithm can be used to give them the best route to the room they are looking for. This configuration requires a digital map of the building but attempts have been made to make this map creation easier. Few beacons per building Beacons can be used in conjunction with pedestrian dead reckoning techniques to add checkpoints to a large open space. PDR uses a known last location in conjunction with direction and speed information provided by the user to estimate a person's location. This technique can be used to estimate a person's location as they walk through a building. Using Bluetooth beacons as checkpoints the user's location can be recalculated to reduce error. In this way a few Bluetooth beacons can be used to cover a large area like a mall. Healthcare Using the device tracking capabilities of Bluetooth beacons, in-home patient monitoring is possible. Using bluetooth beacons a person's movements and activities can be tracked in their home. Bluetooth beacons are a good alternative to in house cameras due to their increased level of privacy. Additionally bluetooth beacons can be used in hospitals or other workplaces to ensure workers meet certain standards. For example, a beacon may be placed at a hand sanitizer dispenser in a hospital – the beacons can help ensure employees are using the station regularly. Tracker One use of beacons is as a "key finder" where a beacon is attached to, for example, a keyring and a smartphone app can be used to track the last time