Identify the types of sampling errors that exist in the following sampling designs: The local newspaper plans to make a prediction for a senatorial election based on a survey of its readers.
A radio show asks people to phone in their views on whether the United States should pay off its debt to China.
A new social media website chooses to survey the first 50 members who join to determine whether members favor the appearance of the homepage.
I, voluntary; II, nonresponse; III, convenience
I, nonresponse; II, voluntary; III, convenience
I, nonresponse; II, convenience; III, voluntary
I, voluntary; II, convenience; III, nonresponse
I, convenience; II, voluntary; III, nonresponse

Acell phone company offers two plans to its subscribers. at the time new subscribers sign up, they are asked to provide some demographic information. the mean yearly income for a sample of 40 subscribers to plan a is $45,000 with a standard deviation of $9,200. for a sample of 25 subscribers to plan b, the mean income is $64,300 with a standard deviation of $7,100. at the 0.025 significance level, is it reasonable to conclude the mean income of those selecting plan b is larger? assume unequal population standard deviations. hint: for the calculations, assume the plan a as the first sample. what is the decision rule? (negative amount should be indicated by a minus sign. round your answer to 3 decimal places.) compute the value of the test statistic. (negative amount should be indicated by a minus sign. round your answer to 2 decimal places.) what is your decision regarding h0 ? reject h0 fail to reject h0 compute the p-value. less than 0.01 between 0.01 and 0.025 between 0.025 and 0.05 between 0.05 and 0.10 greater than 0.10