Chapter 1 - QMB2100 Flashcards
Why study statistics?
- Data is collected everywhere and it requires statistical knowledge to make information useful.
- Statistical information is used to make decisions.
- You need statistical knowledge to understand the world and be conversant in your career.
What are the two types of statistics?
Descriptive and Inferential.
What is descriptive statistics?
Methods of organizing, summarizing, and presenting data in an informative way.
What is inferential statistics?
Methods used to estimate a property of a population on the basis of a sample.
What is a population?
Entire set of individuals or objects of interest.
Sample
A portion of the population of interest.
What are the types of variables?
Qualitative and Quantitative.
What is a qualitative variable?
A variable with nonnumerical characteristic. It can only be counted.
What is a quantitative variable?
A variable that can be reported numerically.
What are the types of quantitative variables?
Continuous and Discrete.
What is a continuous variable?
A variable that can assume any value within a specific range.
What is a discrete variable?
A variable that can assume only certain values and there are “gaps” between those values.
What does the level of measurement determines?
What statistical analysis can be performed, and how data should be summarized and presented.
What are the levels of measurement?
Nominal, Ordinal, Interval, and Ratio.
What is the nominal level of measurement?
Observations of a qualitative variable are measured and recorded as labels or names. They have no order and can only be classified and counted.
What is the ordinal level of measurement?
Observations of a qualitative variable that can be ranked or rated on a relative scale. Data can only be ranked or counted.
What is the interval level of measurement?
It includes all characteristics of the ordinal level, but the interval between the values is meaningful.
What is the ratio level of measurement?
It includes all the characteristics of the interval level of measurement, but the 0 point and the ration between two numbers are both meaningful.
