What is a representative sample?

I want a representative sample of likely voters. I use a telephone directory to randomly select 200 people. What is the most apparent bias?

I want to estimate the average number of hours EHS students spend playing video games. I sample all of my students. What kind of sampling method is this?

I want to estimate how many hours EHS students play video games daily. I get a list of all English classes and randomly select 6 English classes. I survey all the students in those 6 classes. What kind of sampling method is this?

I want to estimate the proportion of all adults in Chula Vista who graduated from high school. I select a random sample of addresses and go to those houses. When an adult answers the door, I ask if they had graduated from high school. If a child answers the door, I ask for an adult. If there is none there at the time, I return at another time to complete the survey. What is the most prominent bias?

I want to estimate the proportion of people in Chula Vista who own cats. I stand outside a local pet store and ask every 4th person whether they own a cat or not. What kind of sampling procedure is this?

I want to estimate the proportion of people in Chula Vista who own cats. I stand outside a local pet store and ask every 4th person whether they own a cat or not. What is the most prominent kind of bias evident?

I want to estimate the proportion of adults in San Diego County who believe that the voting age should be reduced to 17. I get a list of all registered voters in the county and separate that list into several geographic regions and then collect an SRS from each geographic region. What kind of sampling method is this?

I want to estimate the proportion of adults in San Diego County who believe that the voting age should be reduced to 17. I get a list of all registered voters in the county and separate that list into several geographic regions and then an SRS from each geographic region. What kind of bias, if any, is evident in this sampling design?

“Some cell phone users have developed brain cancer. Should all cell phones come with a warning label explaining the danger of using cell phones?”

What kind of bias is evident in this survey question?

Many websites like Amazon and Yelp include customer ratings and reviews of products, restaurants, hotels, and so on. What is the predominant bias evident in these ratings and reviews?

Many websites like Amazon and Yelp include customer ratings and reviews of products, restaurants, hotels, and so on. How does bias affect the ratings and reviews?

A store manager wants to estimate the proportion of all the customers of the store who would use store credit card for their purchases. The manager selects a random sample of 1,000 customers from their customer loyalty program list and sends them a survey asking if they would be interested in applying for a store credit card. Seventy-eight customers respond to the survey. What kinds of biases are evident in this scenario? Select all that apply.

A store manager wants to estimate the proportion of all the customers of the store who would use store credit card for their purchases. The manager selects a random sample of 1,000 customers from their customer loyalty program list and sends them a survey asking if they would be interested in applying for a store credit card. Of the 78 customers who responded to the survey, 70 of them expressed interest in applying for a store credit card. Should the manager be concerned about these results? If so, why? Select all that apply.