Question

State which type of parameter is to be estimated, and the correct method for the following. Do not solve.


(a) In a simple random sample of 400 voters, 210 said that they were planning to vote for the incumbent mayor in the next election. Construct a 95% confidence interval for the proportion of voters who plan to vote for the incumbent mayor in the next election.
The parameter is the population [blank].
The correct method to find the confidence interval is the [blank] method.
Answer
The correct method to find the confidence interval is the [z or t?] method
Answer
DO NOT SOLVE

(b) A simple random sample of size 36 has mean x=3.7 and standard deviation s=1.83. Construct a 99%confidence interval for the population mean.
The parameter is the population [blank].
The correct method to find the confidence interval is the [z or t?] method
Answer
DO NOT SOLVE

(c) A simple random sample of size 39 has mean x=3.97. The population standard deviation is o=1.67. Construct a 90% confidence interval for the population mean.
The parameter is the population [blank] .
The correct method to find the confidence interval is the [z or t?] method.
Answered by GPT-4o mini
The parameter is the population **proportion**.
The correct method to find the confidence interval is the **Wald method** (or **normal approximation method** for proportions).
Answered by GPT-4o mini
The correct method to find the confidence interval is the **z method**.
Answered by GPT-4o mini
The parameter is the population **mean**.
The correct method to find the confidence interval is the **t method**.
Answered by GPT-4o mini
The parameter is the population **mean**.
The correct method to find the confidence interval is the **z method**.