Quantitative vs. Qualitative
Qualitative or quantitative?
Nationalities of passengers on a plane
Qualitative
Party affiliation (Republican, Democrat, Libertarian, etc.) of voters.
Nominal
In a university, a survey of 1641 students found that 479 of them do not know the name of their college's mascot. 479 is a:
I start at the end of a row and I ask every 4th student to respond.
Systematic
Biased or unbiased:
Randomly picking 200 students from the school roster for their favorite ice cream flavor.
Qualitative or quantitative?
Zip codes
Qualitative
9-digit Social Security numbers of a group of citizens.
Nominal
All students that attend the university.
I divide the class into boys and girls, then randomly select 5 members from each group.
Stratified
The difference between interval and ratio data is that ratio data has a(n)...
True/absolute zero
Qualitative or quantitative?
Distances at track events
Quantitative
Satisfaction ratings (scale from "not satisfied" to "very satisfied") by users of a website.
Ordinal
Parameter or statistic:
On a high school football team, 2% of the players are vegetarians.
Parameter
To judge the appeal of a new TV show, a random sample of 10 people were chosen from each of 3 different age categories.
Stratified
Biased or unbiased?
To determine sleeping habits of bears, you study them for 50 random days in the summer.
Biased
True or false:
Data at the ordinal level are qualitative only.
False
Daytime temperature readings (in degrees Fahrenheit) in a 30 day period.
Interval
Identify the sample:
In Florida, a survey of 2500 homeowners found that 1145 of them have switched their homeowner's insurance policy to a different company within the last 3 years.
The 2500 Florida homeowners surveyed.
Determine which scenario represents simple random sampling and which scenario represents random sampling.
a) A fantasy football league commissioner writes the names of 30 teams on slips of paper, throws them in a hat, and draws one team out. All 10 players on that team become the sample.
b) A fantasy football league commissioner assigns a number from 1 to 300 to every individual player in the league. They use a computer random number generator to pick 10 numbers.
a) Random, because while every individual player in the league had a fair, equal 1-in-30 chance of their team being drawn, every possible group of 10 players didn't have an equal chance. It is impossible to get a group made of 5 players from Team A and 5 players from Team B. The group must be an entire team.
b) Simple random, because any combination of 10 players is possible. You could get 10 players from 10 different teams, or 5 from one and 5 from another, etc.
Name the sampling technique: I survey everyone in Mr. Soule's math class and Mr. Ford's sports history class
Cluster
Name each level of measurement for which data can be quantitative
Ordinal, interval, ratio
Heights (in centimeters) of plants in a plot of land.
Ratio
Parameter or statistic?
34% of hockey players surveyed if they left a game through the east exit first played hockey before their 10th birthday.
Statistic
While the class is working in groups of 4, I randomly select a group and ask every member to answer a question.
Cluster
Classify the level of measurement for the data: Distances (in miles) traveled by students commuting to school.
Ratio