Business Statistics Notes
Chapter 1 – What is statistics
Types of statistics
Statistics is a branch of mathematics that transforms data into useful information for
decision makers. There are two types of statistics: descriptive and inferential
Descriptive statistics
Descriptive statistics refer to method of organizing, summarizing and presenting data in
ways that are useful, attractive and informative to the reader
Inferential statistics
Inferential statistics refers to methods used to draw conclusions about characteristics of
a population, based on information available in a sample taken from the population
Key statistical concepts
1. Population – refers to all of the items (individuals, objects, other measurements)
of interest
2. Sample – refers to a portion, part, or subset of the population of interest
3. Parameters – refers to a descriptive measure of a population
4. Statistic – refers to a descriptive measure of a sample
5. Statistical inference – the process of making an estimate, forecast or decision
about a population parameter, based on the sample data. Each statistical
inference must include a measure of reliability of inference – two such measures
include the confidence level and the significance level
6. Confidence level – the proportion of times that an estimating procedure would
be correct
7. Significance level – the relative frequency of a wrong conclusion
Chapter 1 – What is statistics
Types of statistics
Statistics is a branch of mathematics that transforms data into useful information for
decision makers. There are two types of statistics: descriptive and inferential
Descriptive statistics
Descriptive statistics refer to method of organizing, summarizing and presenting data in
ways that are useful, attractive and informative to the reader
Inferential statistics
Inferential statistics refers to methods used to draw conclusions about characteristics of
a population, based on information available in a sample taken from the population
Key statistical concepts
1. Population – refers to all of the items (individuals, objects, other measurements)
of interest
2. Sample – refers to a portion, part, or subset of the population of interest
3. Parameters – refers to a descriptive measure of a population
4. Statistic – refers to a descriptive measure of a sample
5. Statistical inference – the process of making an estimate, forecast or decision
about a population parameter, based on the sample data. Each statistical
inference must include a measure of reliability of inference – two such measures
include the confidence level and the significance level
6. Confidence level – the proportion of times that an estimating procedure would
be correct
7. Significance level – the relative frequency of a wrong conclusion
