A Survey of Crowd Sensing Opportunistic Signals for Indoor Localization

Table 1

Crowd sensing versus expert survey.

Metric	Crowd sensing	Expert survey
Time consumption	High	Medium
Labor cost	Low	High
Trajectory	Unsupervised	Supervised
Data quality	Low	High
Data volume	Large	Small
Coverage	Scalable	Limited
Timeliness	High	Low
Mobile device	Heterogeneous	Dedicated
Wireless connection	Needed	Unnecessary
Carrying mode	Diverse	Fixed
Computational complexity	High	Low
Trustworthiness	Low	High