Population & Samples
I want to survey 100 students at GCHS on their attitudes about the Arts Magnet Program (AMP). Which of the following would be a representative sample?
a. All of the students at GCHS
b. A sample of 100 freshman girls
c. A sample of 25 students per grade
d. A sample of 100 students that are a part of AMP
c. 25 students per grade
Ralphie wanted to know if it's worth asking for a Red Ryder BB Gun for Christmas. He decides to ask 10 of his friends at school what they think about the BB Gun. What type of sampling is this?
Convenience
Suppose I want to know what impact running has on people's knees over time. To investigate this, I tracked the knee health of 100 runners over a period of time. Is this an example of an experiment, survey, or observational study?
observational study
Clark Griswold wants to know whether his family wants him to use his Christmas bonus to put in a swimming pool or to take a trip to Walley World. He asks them to tell him which they prefer. What type of data is this: quantitative or qualitative?
qualitative
A student in Mr. Hessler's MFLA class asked the following question:
Who's the best team in the NFL?
Dallas Cowboys
Denver Broncos
Kansas City Chiefs
New England Patriots
Why is this question biased?
It limits your options to only the ones presented
I want to determine what the most popular fast-food restaurants are amongst senior citizens (age 65+) of Greeley. I survey 100 senior citizens around town. Identify the population and sample in this example.
Population: all senior citizens of Greeley
Sample: sample of 100 senior citizens of Greeley
Santa's elves are making toys for Christmas. Buddy the elf has been assigned to do toy testing since he's a "special elf." He needs to check Jack in the Boxes to make sure they are functioning properly. Buddy decides to test every 10th Jack in the Box that comes to him. What type of sampling is this?
Systematic
Suppose I claim that a new heart medication is effective at reducing the risk of a heart attack. To test this claim I assign 100 people to take the new medication and 100 people to take a placebo. Then, I compare the results of the two groups. Is this an example of an experiment, survey, or observational study?
experiment
I ask each student in my MFLA class how many times in the last month they've skipped my class. Is this an example of discrete or continuous data?
discrete
NBC is creating a poll for the upcoming presidential election. They decide to post a poll on their website and social media. Why is this poll biased?
Possible answers:
only people who have strong opinions will take the time to answer
not everyone has access to internet
only people who follow NBC will even know about the poll
I'm once again surveying people about their favorite NFL team. Now, I want to know who the most popular football team is among seniors at GCHS. I take a random sample of 100 seniors. What is the population and sample in this example?
population: all seniors at GCHS
sample: 100 sampled seniors at GCHS
I just got a new job as a bingo caller! I will get to pull the balls out of the cage and call the numbers. What kind of sampling am I performing as a bingo caller?
Simple Random
I asked random people in downtown Greeley what their favorite Christmas movie is. Is this an example of an observational study, experiment, or survey?
survey
A rancher is weighing his cattle to make sure they are healthy before winter comes. Is this an example of continuous or discrete data?
continuous
Mr. Hessler wants to know what his students think about the final's week schedule this year. He decides to survey all of his sixth and seventh block students to see what they think. Even though this is cluster sampling, why might this survey have biased results?
Sixth and seventh block don't take the final until Thursday, while all the other blocks take the final earlier. Their views are likely to be different than the other classes since they have to wait until the end of the week.
I want to know who the most popular NFL team is in the state of Wyoming. I decide to randomly select 500 households in Cheyenne to send surveys to. Surprisingly, I get a great response rate of 90%! Is this a representative sample? Why or why not?
No, Cheyenne isn't representative of the state of Wyoming. I should have randomly selected people from the whole state.
I want to know what the teachers at GCHS think about the new cell phone rules. I decide to ask all of the teachers in the math department and history department what they think. What type of sampling is this?
Cluster
I want to know if people who smoke cigarettes or people who smoke marijuana have a higher risk of developing lung cancer. I recruit 100 volunteers (50 cigarette smokers and 50 marijuana smokers) to screen for lung cancer every year for the rest of their lives. Is this an observational study, experiment, or survey?
observational study
I want to find out what the average height of a girls' high school basketball player is at GCHS. I ask all of the members of the team what their height is? What type of data is this: quantitative or qualitative?
quantitative
The mayor wants to know what people in the community think about a proposed law that requires people to keep the public sidewalks in front of businesses and residences shoveled in the winter. He decides to randomly mail out surveys to people in the community. Besides, non-response bias, what else could be a problem with this sampling method?
Not everyone has a sidewalk. Some people live in apartment complexes, outside of town, etc.
Parameter: percentage of all the rancher's cows that have brucellosis
Statistic: percentage of the sampled cows that have brucellosis
I randomly select 10 students from each of my MFLA classes to share their thoughts on my homework policy. What type of sampling is this?
Stratified
I want to know if spoilers actually increase the gas mileage of a car by making it more aerodynamic. I test 10 different models of cars that have spoilers. I drive the car on a course with the spoiler and record how much gas was used, then I remove the spoiler and repeat the process. Then, I compare the amount of gas used with and without the spoiler. Is this an example of an observational study, experiment, or survey?
experiment
The average height of a woman in the US is 5 ft 4 in. I want to know if our girls' basketball team at GCHS has more players that are taller than average or shorter than average. I ask each player their height, then record each player as being taller than or shorter than average. What type of data is this: quantitative or qualitative?