Q1 Data Logic Flashcards
If 3 people can paint 3 fences in 3 hours, how long would it take 1 person to paint 1 fence?
3 hours
If cold water alone fills the tub in 30 minutes, and hot water alone fills the tub in 1 hour, how long does it take to fill the tub if both cold and hot water are turned on?
60 minutes divided by 3 tubs = 20 minutes
Belief
- A firmly held conviction
- Not false, but not evidence
Evidence
- Facts or information that support a statement
- Do not include beliefs
- Support may or may not be proof
Proof
Implies truth or certainty
Do you believe crime has increased or decreased?
Most Americans say crime has INCREASED, even though evidence shows it has DECREASED, because this belief has been reinforced through politicians or news programs
Is the data about “rate of reported violent crime per 100,000 US residents” proof?
No, because not all crime is reported
Why is there a gap between belief and evidence?
Belief can be more powerful than facts, and when we trust beliefs more than evidence, we can misinterpret data
Confirmation bias
Selecting or interpreting evidence in a way that confirms pre-existing beliefs
Hypothesis
A testable proposition or an educated guess
Theory
- An overarching explanation, a system of ideas
- Often misused as “guesses”
Are movie “theories” really theories?
No, they are hypotheses
Is the “Big Bang Theory” really a theory?
Yes, because it is an overarching explanation for the origins of the universe
How do scientists utilize theories?
- They use theory to develop a hypothesis which can be tested with data
- It is NOT a guess
Should theories be dismissed because they are “unproven”?
- No, because every theory is unproven
- If they were proven, they would be a law
Can theories be disproven?
Yes, for example, the mass society theory
Can theories be supported, but not proven?
Yes, for example, social learning
Can a hypothesis or theory be proven true?
No, neither can be proven true, only supported or rejected
Error
- Uncertainty that occurs naturally
- It is a limitation, not a mistake
Sampling error
The expected variance between a population and a representative sample
Sample
Subset of a population
Representative sample
- Closely reflects a population
- Leaves room for uncertainty or sampling error
- Best obtained at random
Non-representative sample
- Self-selected groups or clubs
- Can be useful, but not intended to represent a population
Population
Everyone or everything
Which is more important? Freedom to pursue life’s goals without state interference, or the state ensures no one is in need?
No one is in need: 35%
Freedom: 58%
Sampling error: + or - 4 percentage points
- True measure of public opinion for “No one is in need” was somewhere between 31% and 39%
- True measure of public opinion for “Freedom” was somewhere between 54% and 62%
- Limitation is that exact numbers are unknown
- Public’s opinion is within these ranges
Two types of crime
- Property crime (burglary, theft)
- Violent crime (robbery, homicide)
- The combination of both: Total crime
How are the types of crime misinterpreted by politcians?
They will say “crime” as a general statement, when they just mean one category of crime, such as homicide
How are income and wealth different?
- Income: money you earn, like pay from a job
- Wealth: stuff you own, like a car or computer
How do politicians misinterpret income and wealth?
- They will say wealth is “too concentrated” and we must “raise income taxes”
- Even though they know income is not the same as wealth
How is the role of human involvement evident in the term “unemployment”?
- The government divides the total unemployed by the labor force
- The labor force includes the employed and unemployed, and excludes full-time parents
- Unemployed includes those without a job AND are actively looking, and excludes those who are discourages and have been inactive > 4 weeks, and the underemployed
How is “middle class” a vague definition?
- Lacks a common definition
- Less of a measurement than an ideal
- Data cannot be compared fairly
How is “autism” a changing definition?
- Autism increasing throughout the years is not due to an “epidemic,” but due to an increase in awareness
- The definition has loosened and more conditions have been added, so more people are being diagnosed
Why do movie ratings differ so much on IMDb compared to Rotten Tomatoes?
- IMDb shows ratings from registered users on their website
- Rotten Tomatoes shows ratings from movie critics
Why did UF Black student enrollment drop after 2010?
Added new category in 2010 when choosing what race you are, so some Black people who would have chosen “Black” previously chose the new category “Two or more races”
Why did Belgium have such a high COVID-19 fatality rate at the start of the pandemic?
Chose to count all suspected deaths while no other country did
Source types
- Sample
- Observation
- Self-report
- Estimation
You need to know the origin of what type of source?
Samples
Why was the report of infection rates at the beginning of the COVID-19 pandemic unreliable?
- Only counted those tested
- People were only tested early on if they had serious symptoms, so they all were really sick
- Was not random or representative
Why are reviews on Yelp, TripAdvisor, or Rate My Professors unreliable?
Not representative because reviews usually come from those extremely pleased or extremely unhappy
Observation
As a data source, observation is a systematic measurement, often in natural settings
How do volunteers use observation to monitor avian health?
- They count and categorize all birds in specific areas
- Careful and systematic
How does the annual homeless count use observation?
- Conducted one day each January
- Volunteers count every person for a census, with a shelter, and without a shelter
- Careful and systematic
Self-report data
Originate with individuals and cannot be measured independently
Estimation
- Derived from informal guesses of inherently unmeasurable phenomena
- Does NOT mean a rough guess
How is UF’s estimation of its impact on the state economy at $16 billion an estimation?
- It is precise, but an estimate
- Based on informed guesses
- Economic impact of US is unknowable
Ex. Walmart last year had a net profit of $15 million on sales of $534 million. Is that a lot?
- UF spends $3 billion annually
- If UF alone spends that much, then the biggest store on the planet should probably be spending more
- The “millions” should be BILLIONS
Florida has about 21 million people. Is that a lot?
- Florida ranks third in population behind Texas and California
- It is the third largest state
About 35 million Americans have flu symptoms each year. Is that a lot?
- Compare with total population of people in the US: 330 million
- Roughly 35 million figure means about 1 in every 10 Americans
- World population: 7.6 billion
- 7.6 billion means 1 in every 25 global citizens lives in the US
- US population ranks third
If an ATM was spitting out $100 a second, how long would it take to get to $1 million?
3 hours
If an ATM was spitting out $100 a second, how long would it take to get to $1 billion?
116 days, or almost 4 months
If an ATM was spitting out $100 a second, how long would it take to get to $145 billion?
46 years
How much would an ATM have to spit out every second to pay the government’s annual bill of $4.7 trillion?
Almost $150,000 per second
