Consider the following situation, and answer each of the following multiple choice questions. In your write-up, just list the sub-question letter (A-J) and your answer – no need to restate the question or to justify your answer.
Situation: You have 400 data points, which are normally distributed with a mean of 90 and a standard deviation of 10. All scores are integers. Then one new data point is added, which is far above the top end of the distribution. (Thus, the new data point has the very highest score in the distribution, by a considerable margin.)
A. When the new data point is added, what happens to the sample size (N)?
B. When the new data point is added, what happens to the mean?
C. When the new data point is added, what happens to the value of the mode?
D. When the new data point is added, what happens to the number of modes in the distribution?
E. When the new data point is added, what happens to the range of the distribution?
F. When the new data point is added, what happens to the standard deviation?
G. Assuming the standard deviation of the old distribution was greater than 1, when the new data point is added, what happens to the value of the variance of the new distribution?
H. When the new data point is added, what happens to the value of the skewness of the distribution?
I. What happens to the value of the z score of the old mean calculated using the 401 data points, compared to the value of the z score of the old mean calculated using only the original 400 data points?
J. What happens to the value of the z score of the new mean calculated using the 401 data points, compared to the value of the z score of the old mean calculated using the original 400 data points?
We do not do your homework for you. Although it might take more effort to do the work on your own, you will profit more from your effort. We will be happy to evaluate your work though.
However, I will start it for you.
A. 400 + 1 = 401
can you at least explain what i can do in order to ge the answer to g-j?
I also need help with this question!!!!
Same here, can you be more detailed with letter A?
A. When the new data point is added, the sample size (N) increases by 1.
B. When the new data point is added, the mean increases.
C. When the new data point is added, the value of the mode remains the same.
D. When the new data point is added, the number of modes in the distribution remains the same (assuming no other data points have the same value as the new data point).
E. When the new data point is added, the range of the distribution increases.
F. When the new data point is added, the standard deviation increases.
G. Assuming the standard deviation of the old distribution was greater than 1, when the new data point is added, the value of the variance of the new distribution increases.
H. When the new data point is added, the value of the skewness of the distribution may change, depending on the location of the new data point in relation to the other data points.
I. The value of the z score of the old mean calculated using the 401 data points will be the same as the value of the z score of the old mean calculated using only the original 400 data points. Adding one new data point does not change the z score of the mean.
J. The value of the z score of the new mean calculated using the 401 data points will be different from the value of the z score of the old mean calculated using the original 400 data points. The addition of the new data point will likely change the distribution characteristics and therefore the z score of the new mean.