In some research, the researchers are not able to use random assignment to divide participants among groups. instead, they compare preexisting groups. what type of research is this?

Because jaedyn is a sociable, gregarious child, she tends to be noticed by her teachers and peers. how does jaedyn interact with her environment?

What decision were made by the first congress during its first year that shape the future of the government

According to the federal regulations, which of the following studies meets the definition of research with human subjects? a study of twenty 4th grade classrooms in which researchers ask the schools to systematically vary the time of day reading is taught, and collect weekly assessments of reading comprehension for each child over a three-month period.the collection of data, by a playground designer hired by the superintendent of schools, about the physical dimensions of school playgrounds, presence of fencing, and the kinds of equipment currently provided.a feasibility study for implementing a year-round school program, focusing on economic issues such a facilities utilization and transportation costs.an analysis of aggregate data comparing statewide high school graduation rates provided by the state department of public instruction, using county tax information.