Author Question: The confidence interval for five-year survival after Stage I breast cancer in a large sample of ... (Read 89 times)

appyboo · **on:** Jul 8, 2018

The confidence interval for five-year survival after Stage I breast cancer in a large sample of women living in Texas is 87.5 to 93.3, at a p <.05 level of significance. What does this mean? (Select all that apply.)

a. Texan women in the near future will be likely to have about a 90 chance of living five years after they are newly diagnosed with Stage I breast cancer.
b. Women in Texas with Stage I breast cancer have a 95 chance of 90 survival, over a five-year period.
c. Women in Texas with Stage I breast cancer have an 86 chance of five-year survival.
d. In any sample of women in Texas newly diagnosed with Stage I breast cancer, there is about a 95 chance that their collective survival five years from now will be around 90.
e. Women in Texas can feel 95 confident that they will survive Stage I breast cancer.

Question 2

There is a data set A: 3, 3, 3, 5, 6, 6, 8, 9, 9, 12, 13. The data set B is created. It is identical to A, except for its much larger last value. Data set B: 3, 3, 3, 5, 6, 6, 8, 9, 9, 12, 83.

What is the effect of increasing the largest value upon the descriptive statistics of the data set? (Select all that apply.)
a. The mean increases.
b. The median increases.
c. The mode increases.
d. The set's distribution changes from perfectly normal to somewhat skewed.
e. The standard deviation increases.
f. The variance increases.
g. The range increases.

SomethingSomething · **Reply #1 on:** Jul 8, 2018

Answer to Question 1

ANS: A, D
To determine how closely the sample mean approximates the population mean, the standard error of the mean is used to build a confidence interval. For that matter, a confidence interval can be created for many statistics, such as a mean, proportion, and odds ratio. At the p <.05 level, it merely signifies that there is a window of possibilities, and future samples have a 95 chance of falling within that window.

Answer to Question 2

ANS: A, D, E, F, G

The mode is the numerical value or score that occurs with the greatest frequency in a data set; unless this is the largest value, the mode will be unaffected. The median (MD) is the score at the exact center of the ungrouped frequency distribution; it is unaffected by a change in the value of the largest value. The mean is the arithmetic average of all a variable's values in a study and is the most commonly reported measure of central tendency. The mean is sensitive to extreme scores such as outliers, and it will be affected by a large increase in the largest value. Measures of dispersion or variability are measures of individual differences of the members of the population and sample. Since they indicate how different the scores are, they all are affected by an extreme value.