Chapter 1 Flashcards
(23 cards)
What are data?
Data is the plural form.
Any collection of numbers, characters, images, or other items that provide information about something.
In a database, rows are called _______ or _____, and in any event the rows represent the ___ of the data.
records; cases; who.
A common place to find out exactly what each row refers to is the __________ column.
leftmost
What is needed to know to analyze data?
who and what;
The first step of any data analysis is to know what you are trying to accomplish and what you want to know.
Define variables.
A characteristic of an individual population unit (case).
They are usually found as the columns of a data table with a name in the header that identifies what has been recorded.
What are two types of variables?
Categorical (Qualitative) and Quantitative.
What are examples of categorical variables?
State/Country, Area Code, Martial Status, Sex, Race.
What are quantitative variables?
A variable that contains measured numerical values with measurement units.
What are categorical variables?
A variable that names categories with words or numerals.
What is an identifier variable?
A categorical variable that records a unique value for each case, used to name or identify it.
Student ID, Social Security number.
What is a sample?
A subset of a population, examined in hope of learning about the population.
What is a population?
The entire group of individuals or instances about whom we hope to learn.
What are two statistical methods?
Descriptive Statistics, Regression, Probability Distribution and Inferential Statistics.
Define descriptive statistics.
Numerical characteristics taken from a sample used to describe a sample.
Define inferential statistics.
Numerical characteristics taken from a sample used to make inferences about the population.
Define statistic.
A numerical characteristic of a sample.
Define parameter.
A numerical characteristic of a population.
What is the relationship between statistics and parameters?
We use statistics to estimate population parameters due to lack of resources (money and/or time) to look at the entire population.
Define categorical data.
Measurements classified into a category.
Define quantitative data.
Measurements recorded on a naturally occurring numerical scale.
When finding “who”, what question should be asked?
Who is in the data?
Individuals (people), subjects, respondents (in surveys), participants, experimental units (animals, plants, inanimate objects.Its values are text and those values tell us what category the particular case falls into).
When finding “what”, what question should be asked?
What variables are being measured?
Columns of the data table (categorical or quantitative).
Define case,
An individual about whom or which we have data.
