Statistical tests require both a(n) _____ and a(n) _____ hypothesis

Daniel is interested in studying how children's behavior changes when they grow up in high-risk environments. He enlists 500 children and their parents to take part in his research, and observes these children once a year for 20 years

Despite the fact that this research is very time consuming and expensive, it gives very good information about how the children age over time. This type of research is an example of a __________ study. A) sequential B) cross-sectional C) longitudinal D) continuous

When John was an infant, his parents noticed that he didn't achieve his developmental milestones on time

As he grew older, he seemed not to be able to do what his same-aged peers could do. Concerned, John's parents took him to get an IQ test. The psychologist reported that he scored about a 62 overall. Now at age five, John still cannot dress himself, tie his shoes, nor feed himself very well. John probably has been diagnosed with _____. Fill in the blank with correct word