QNT 2020 MIDTERM EXAM VERIFIED STUDY GUIDE
Definition of observation - Answers - one single unit of analysis in the data that we want
to study
Definition of variable - Answers - a characteristic of the subject or individual, measured
by each observation
Categorical Data - Answers - (Qualitative data) Such as a verbal label (e.g. vehicle
name) or a coded label (e.g. type 1, type 2, etc.)
Discrete Numerical Data - Answers - The values are separate and countable, there is
not infinite divisible/observable gaps between values
Continuous Numerical Data - Answers - These can take an infinite amount of values
within a range, either something you measure, or a random outcome you expect to
happen as result of experimentation that falls within a predicted range
Random Sampling Methods - Answers - Simple Random Sample: Uses Random
numbers to select items from a list
Systemic Sample: Selects every #th item from a list or sequence
Stratified Sample: Selects randomly within a defined strata (e.g., age, job, gender)
Cluster Sample: Selects from random geographical regions that represent the
population
Non-Random Sampling Methods - Answers - Judgement Sample: Uses expert
knowledge to choose "typical" items
Convenience Sample: Uses a sample that happens to be available
Focus Groups: In-depth dialog with a representative panel of individuals
Sample vs Population - Answers - A sample is a subset of the population which is
easier to observe, meanwhile the population is everyone, which is nearly impossible to
observe.
Population Parameter - Answers - A measurement or characteristic of the population
(e.g. mean or proportion) Usually unknown since we can rarely observe the entire
population (Usually represented by a Greek Letter like μ or pi)
Population Statistic - Answers - A numerical value calculated from a sample (e.g. mean
or proportion) (usually represented by a Roman letter like bar or p)
Central Tendency Measurements - Answers - Highlights where most data points cluster
(Mean, Median, Mode)
Definition of observation - Answers - one single unit of analysis in the data that we want
to study
Definition of variable - Answers - a characteristic of the subject or individual, measured
by each observation
Categorical Data - Answers - (Qualitative data) Such as a verbal label (e.g. vehicle
name) or a coded label (e.g. type 1, type 2, etc.)
Discrete Numerical Data - Answers - The values are separate and countable, there is
not infinite divisible/observable gaps between values
Continuous Numerical Data - Answers - These can take an infinite amount of values
within a range, either something you measure, or a random outcome you expect to
happen as result of experimentation that falls within a predicted range
Random Sampling Methods - Answers - Simple Random Sample: Uses Random
numbers to select items from a list
Systemic Sample: Selects every #th item from a list or sequence
Stratified Sample: Selects randomly within a defined strata (e.g., age, job, gender)
Cluster Sample: Selects from random geographical regions that represent the
population
Non-Random Sampling Methods - Answers - Judgement Sample: Uses expert
knowledge to choose "typical" items
Convenience Sample: Uses a sample that happens to be available
Focus Groups: In-depth dialog with a representative panel of individuals
Sample vs Population - Answers - A sample is a subset of the population which is
easier to observe, meanwhile the population is everyone, which is nearly impossible to
observe.
Population Parameter - Answers - A measurement or characteristic of the population
(e.g. mean or proportion) Usually unknown since we can rarely observe the entire
population (Usually represented by a Greek Letter like μ or pi)
Population Statistic - Answers - A numerical value calculated from a sample (e.g. mean
or proportion) (usually represented by a Roman letter like bar or p)
Central Tendency Measurements - Answers - Highlights where most data points cluster
(Mean, Median, Mode)
