researcher will either use random assignment or matching What do random assignment and matching have in common? They are both designed to create equivalent groups of participants. Random assignment is to random selection as _____ is to _____
1 An unarmed guard from 21st Sentry Security in Dallas-Fort Worth typically costs $14 per hour, while an armed guard starts at $18 per hour. 2  The time of day also affects pricing. 3  Security guards working at a late-night party in the city may cost $30-$50 per hour, for example.
1 Installation of an advanced car security system can cost $100-$450 or more, depending on the complexity, the ease of access for the make and model of vehicle, and labor rates (as a general rule, labor costs more on a luxury, high-end vehicle than on a lower-priced standard sedan). Installation of an advanced car security system can cost $100-$450 or more, depending on the complexity, the ease of access for the make and model of vehicle, and labor rates (as a general rule, labor costs more on a luxury, high-end vehicle than on a lower-priced standard sedan).