Stats Big Picture
You see a chart showing that the average lifespan in a country has increased over the last 50 years. What is this an example of?
A statistic or an example of descriptive statistics.
A student's height, recorded in inches, is an example of this type of variable.
A numeric variable.
The temperature in Celsius or Fahrenheit is an example of this type of measurement scale.
Numerical - Continuous
A study on a new drug is funded by the drug's manufacturer. This is a potential source of
Bias
What is the primary benefit of using a simple random sample?
It is the least biased method and provides a sample that is most likely to be representative of the population.
It's collected within a context or for a purpose.
A population
A survey asks for a person's favorite color. What type of variable is this?
A categorical variable.
A variable that represents the order in which runners finish a race (1st, 2nd, 3rd) uses this scale of measurement.
Categorical, ordinal
You survey your friends and family about their favorite band to represent the entire school's opinion. Name the bias
Convenience bias
What is a significant pro of using a convenience sample?
It is easy, quick, and inexpensive to collect data.
A pollster surveys 1,000 voters out of 100 million registered voters to predict the outcome of an election. The 1,000 voters represent this.
A sample
What is the defining characteristic that makes a piece of information "data"?
Variable
What is the scale of measurement used for a variable like the number of siblings a person has?
Numerical - discrete
A researcher wants to study the relationship between exercise and heart health, but they don't account for diet. Diet could be...
Confounding variable
What is the primary disadvantage or con of using a convenience sample?
It is highly prone to bias because the sample is unlikely to be representative of the larger population.
What is the name of the process by which we use information from a sample to draw conclusions about a larger population?
Inference
How do variables relate to sample data in a structured dataset?
characteristics of observations
This measurement scale has a true zero point, meaning that a value of zero represents the complete absence of the measured attribute.
Numeric - discrete
Error that occurs between the sample and population
Sampling error
A researcher divides a city into different neighborhoods and then randomly selects a few neighborhoods to survey. What is this sampling method called?
Stratified random sampling
The percentage of people who prefer a new soft drink flavor is an example of statistics in the real world. Give another example.
True and give an example.
What is the difference between a numeric variable and a categorical variable?
A numeric variable represents a quantity that can be measured with numbers (e.g., age, height), while a categorical variable represents a quality or characteristic that can be placed into categories (e.g., gender, favorite color)
A ranking of favorite ice cream flavors (1st, 2nd, 3rd, etc.) uses which measurement scale?
Categorical, Ordinal
How does sampling bias impact our ability to generalize findings from our sample to the broader population?
Sampling bias leads to a sample that isn't representative of the population, meaning the conclusions drawn from the sample are likely to be inaccurate when applied to the broader population. It makes generalization difficult or impossible.
A student surveys people in their dorm about the best study spots on campus to represent the entire student body. What type of sampling method is this, and why would this method be expected to have a large sampling error?
Convenient, large sampling error not representative of the population.