ch1 flashcards_statistics
(30 cards)
What are the Five W’s used in data analysis?
Who, What, When, Where, Why (and sometimes How).
What does ‘Who’ represent in data?
The cases or individuals for which data are collected.
Give an example of a categorical variable.
Gender, race, or types of cars.
What is the Area Principle?
The area occupied by a part of a graph should correspond to the magnitude of the value it represents.
How do segmented bar charts differ from pie charts?
Segmented bar charts display information as bars, making comparisons easier.
Define a contingency table.
A table that examines relationships between two categorical variables.
What is the formula for the Complement Rule?
P(A) = 1 - P(A^c)
what is the multiplication rule of probability for independent events? Stats ch1
P(A and B) = P(A) × P(B).
What is the Addition Rule for disjoint events?
P(A or B) = P(A) + P(B).
What is the Law of Large Numbers (LLN)?
As trials increase, the relative frequency of events approaches the true probability.
What are the three parts of statistical processes?
Data Analysis, Probability, Statistical Inference.
waht type of table is a categorical variable summarized on?
Using frequency or relative frequency tables.
What is a key feature of ordinal variables?
They have a logical order but do not measure precise quantities.
Give an example of primary data. Stats ch 1
Survey data collected directly by researchers.
Define time series data.
Data measured at intervals over time (e.g., daily stock prices).
What is a nominal variable? In types of data stats
A categorical variable with no inherent order (e.g., car models).
What is the general formula for non-disjoint events?
P(A or B) = P(A) + P(B) - P(A and B).
What are identifiers in data?
Unique labels for individuals or cases (e.g., Transaction Numbers, IDs).
What is the difference between empirical and subjective probabilities?
Empirical is based on observed data; subjective relies on expert judgment.
What does a pie chart best represent?
Parts of a whole, where each slice is proportional to its category.
Define cross-sectional data.
Data measured at one point in time (e.g., monthly revenue by location).
What is the purpose of a Venn diagram in probability? 2 circles
To illustrate relationships between events, such as overlaps and disjoint sets.
What is the probability assignment rule?
The probabilities of all possible outcomes must sum to 1.
What is statistical inference?
Drawing conclusions about a population using sample data and probability.
