A researcher is interested in whether students who attend private high schools have higher average SAT scores than students in the general population. A random sample of 90 students at a private high school is tested and has a mean SAT score of 1050. The average score for public high school students is 1000(ó= 200). Is this a one or two tailed test?
Since you are only concerned with finding if the sample mean is greater than the population mean, it is a one-tailed test.
Ho: mean = 1000
Ha: mean > 1000
To determine whether this is a one-tailed or two-tailed test, we need to understand the hypothesis being tested.
In this scenario, the researcher wants to compare the average SAT scores of students in private high schools to those in the general population. Therefore, the researcher is interested in whether the average SAT scores of students in private high schools are higher or lower than the average for the general population.
If the researcher is only interested in testing whether the average SAT scores of students in private high schools are higher than the general population, it would be a one-tailed test. This is because the researcher is only looking for a difference in one direction, specifically, higher SAT scores in private high schools.
On the other hand, if the researcher is interested in testing whether the average SAT scores of students in private high schools are different (higher or lower) than the general population, it would be a two-tailed test. This is because the researcher is looking for a difference in either direction, not just higher SAT scores.
Without more information about the researcher's specific hypothesis or research question, it's difficult to definitively determine if it is a one-tailed or two-tailed test.