Statistical Power. The Statistical Data Analysis tutorial page provides a good background for understanding the concept of statistical power. In very basic terms, statistical power is the likelihood of achieving statistical significance, when in fact the alternative hypothesis is true.
In 2001, the U.S. Census Bureau estimated that nearly 7 million school-age children are routinely left home alone. âDevelopmentally, children are generally ready to be home alone around the age of 12 or 13,â says Cherie Sage, State Director of Safe Kids Kansas.
Most places believe that 12 or 13 is okay to leave home alone for a couple of hours during daylight hours.   Legal Age   There are very few states in the U.S. with legal minimum ages for children home alone, but many state agencies have published guidelines. child has to be 18 to be left home alone in NJ. We have a friend whose parents went away for a week. My brother was staying with them (he was 1 month away from being 18).