The single-sample t-test compares the mean of the sample to a given number (which you supply). The dependent-sample t-test compares the difference in the means from the two variables to a given number (usually 0), while taking into account the fact that the scores are not independent.The independent samples t-test compares the difference in the means from the two groups to a given value (usually 0).he single sample t-test tests the null hypothesis that the population mean is equal to the given number specified using the option H0=. In our example, the t-value for variable write is 4.14 with 199 degrees of freedom.
Vermont had the second-highest median age, at 42.3 years. New Hampshire was third, with a median age of 42. Utah was the youngest state, with a median age of 29.9 years. Officials say among Maine counties, Lincoln is the oldest with a median age of 49.4 years. Androscoggin County was the youngest, at 40.5 years.
But the states with the most elderly do not necessarily have the oldest population age profiles. California is still a relatively young state even though it has the greatest number of elderly residents: Less than 11 percent of the state's total population was age 65 or older in 2000. In contrast, nearly 18 percent of Florida's population was age 65 or older, the highest proportion of any state (see table).