An independent research firm conducted a study of 100 randomly selected children who were participating in a program advertised
to improve mathematics skills. The results showed no statistically significant improvement in mathematical skills, using a significance level of 0.05. The program is effective, which of the following would be an appropriate method for increasing power in this context? a. Increase the sample size to 200 children.
b. Use a two-sided test instead of a one sided test.
c. Decrease the sample size.
d. Use alpha-0.01 instead of a-alpha.
e. Use a one sided test instead of a two-sided test.
b) use a two-sided test instead of a one sided test.
Step-by-step explanation:
If we are using a significance level of 0.05, then the two-tailed test assigns half alpha to test for statistical significance in one direction and half alpha to test statistical significance in the other direction. This implies that .025 is present in each tail of the test statistical distribution. When using the two-tailed test, regardless of the direction of the relationship you assume, we test the possibility of the relationship in both directions.
there must be at least two lines on any plane because a plane is defined by 3 non-collinear points. Explanation: ... These lines may or may not intersect. If two of the 3 points are collinear, then we have a line through those 2 points as well as a line through the 3rd point.
The number of remaining problems is: 30-20 = 10 problems. The amount of time remaining is: 40-25 = 15minutes For the first 20 problems the time per problem is: t1 = 25/20 = 5/4 minutes For the remaining problems the time per problem is: t2 = 15/10 = 3/2 minutes Answer: you will be able to spend about 3/2 minutes on each remaining problem