Question

1. A random sample is collected. The 95% confidence interval of the population mean based on this sample is calculated at [14.20, 15.80]. What is the 99% confidence interval from the same sample?

1. [14.164, 15.842]
2. [14.123, 15.884]
3. [13.968, 16.032]
4. [13.880, 16.128]
5. [13.802, 16.208]

1. America Corporation, a major auto manufacturer, wants to test the effectiveness of its "fair and frank" ad messages in changing the existing negative attitudes of the public toward the company's performance to offer a better product.

1. The dependent variable in this study is sales level after the ad campaign is completed.
2. The dependent variable in this study is the attitude of the population concerning the company's performance to offer a better product.
3. The independent variable is the ad campaign with the "fair and frank" messages.
4. The independent variable is the existing negative attitudes of the public.

1. 1 and 3
2. 1 and 4
3. 2 and 3
4. 2 and 4
5. None of the above

Answer 1