A PHP Error was encountered
Severity: Notice
Message: Undefined index: userid
Filename: views/question.php
Line Number: 212
Backtrace:
File: /home/mycocrkc/statisticsanswered.com/application/views/question.php
Line: 212
Function: _error_handler
File: /home/mycocrkc/statisticsanswered.com/application/controllers/Questions.php
Line: 416
Function: view
File: /home/mycocrkc/statisticsanswered.com/index.php
Line: 315
Function: require_once
The population proportion of adults who think the president of their country can control the price of gasoline
A researcher wishes to estimate, with 95% confidence, the population proportion of adults who think the president of their country can control the price of gasoline. Her estimate must be accurate within 4% of the true proportion.
a) No preliminary estimate is available. Find the minimum sample size needed.
b) Find the minimum sample size needed, using a prior study that found that 42% of the respondents said they think their president can control the price of gasoline.
c) Compare the results from parts (a) and (b).
------
(a) What is the minimum sample size needed assuming that no prior information is available?
(b) What is the minimum sample size needed using a prior study that found that 42% of the respondents said they think their president can control the price of gasoline?
(c) How do the results from (a) and (b) compare?