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A biased sampling situation is described. In each case, give: (a) The sample (b) The population of interest (c) A population we can generalize to given the sample To estimate the average number of tweets from all twitter accounts in \(2015,\) one of the authors randomly selected 10 of his followers and counted their tweets.

A biased sampling situation is described. In each case, give: (a) The sample (b) The population of interest (c) A population we can generalize to given the sample To investigate interest across all residents of the US in a new type of ice skate, a random sample of 1500 people in Minnesota are asked about their interest in the product.

State whether or not the sampling method described produces a random sample from the given population. The population is the approximately 25,000 protein-coding genes in human DNA. Each gene is assigned a number (from 1 to 25,000 ), and computer software is used to randomly select 100 of these numbers yielding a sample of 100 genes.

State whether or not the sampling method described produces a random sample from the given population. The population is adults between the ages of 18 and 22. A sample of 100 students is collected from a local university, and each student at the university had an equal chance of being selected for the sample.

State whether or not the sampling method described produces a random sample from the given population. The population is all trees in a forest. We walk through the forest and pick out trees that appear to be representative of all the trees in the forest.

Indicate whether we should trust the results of the study. Is the method of data collection biased? If it is, explain why. Ask a random sample of people in a given school district, "Excellent teachers are essential to the well-being of children in this community, and teachers truly deserve a salary raise this year. Do you agree?" Use the results to estimate the proportion of all people in the school district who support giving teachers a raise.

Indicate whether we should trust the results of the study. Is the method of data collection biased? If it is, explain why. Take 10 apples off the top of a truckload of apples and measure the amount of bruising on those apples to estimate how much bruising there is, on average, in the whole truckload.

Indicate whether we should trust the results of the study. Is the method of data collection biased? If it is, explain why. Take a random sample of one type of printer and test each printer to see how many pages of text each will print before the ink runs out. Use the average from the sample to estimate how many pages, on average, all printers of this type will last before the ink runs out.

Wearing a Uniform to Work The website fox6now.com held an online poll in June 2015 asking "What do you think about the concept of having an everyday uniform for work, like Steve Jobs did?" Of the people who answered the question, \(24 \%\) said they loved the idea, \(58 \%\) said they hated the idea, and \(18 \%\) said that they already wore a uniform to work. (a) Are the people who answered the poll likely to be representative of all adult workers? Why or why not? (b) Is it reasonable to generalize this result and estimate that \(24 \%\) of all adult workers would like to wear a uniform to work?

Climate Change In July 2015, a poll asked a random sample of 1,236 registered voters in Iowa whether they agree or disagree that the world needs to do more to combat climate change. \({ }^{26}\) The results show that \(65 \%\) agree, while \(25 \%\) disagree and \(10 \%\) don't know. (a) What is the sample? What is the intended population? (b) Is it reasonable to generalize this result and estimate that \(65 \%\) of all registered voters in Iowa agree that the world needs to do more to combat climate change?