Samples and surveys (article) | Study design

When we collect data it's important to know what type of data we're collecting and how to collect it properly.

Problem 1: Qualitative and quantitative data

A survey was given that included data on each student's field of interest, age in years, number of languages spoken, and handedness.

	David	Becca	Paige	...
Field of interest	computer science	journalism	chemistry	...
Age (years)	$13$ ‍	$15$ ‍	$14$ ‍	...
Languages spoken	$2$ ‍	$1$ ‍	$1$ ‍	...
Handed	right	left	right	...

question a

Is "field of interest" qualitative or quantitative?

Question b

Is "age (years)" qualitative or quantitative?

Question C

Is "languages spoken" qualitative or quantitative?

Question D

Is "handed" qualitative or quantitative?

Problem 2: Representative samples

question a

Jillian wants to know what percent of students at her school watch sports on TV. Which strategy for sampling will be more likely to produce a representative sample?

question b

Theo wants to know what percent of students at his school have a computer. Which strategy for sampling will be more likely to produce a representative sample?

(Choice A)
Get an alphabetized list of the names of all students in the school, and pick every tenth student on the list to survey.
(Choice B)
Send an email to every student asking them if they have a computer, and count the first $50$ ‍ surveys that get returned.

Problem 4: Biased wording in survey questions

Willy wants to find what percent of students drink the milk after they finish their cereal. Which survey question below is the most unbiased?

Course: Statistics and probability > Unit 6

Samples and surveys

Problem 1: Qualitative and quantitative data

Problem 2: Representative samples

Problem 3: Sampling methods

Problem 4: Biased wording in survey questions

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