BUSINESS STATISTICS CHAPTER 07
Statistical inferences mean to use statistics calculated from samples to estimate the values of
The main concern of statistical inferences is about the population, not a sampl
BUSINESS STATISTICS CHAPTER 02
Pie chart and bar chart:
If comparison between categories is important, use a bar chart.
o Vertical bar chart is for numeric variables.
o Horizontal bar chart is for word variables.
If observing the portion of each categ
BUSINESS STATISTICS CHAPTER 09
The null hypothesis
The null hypothesis H0 is always one of status quo (when certain process operates correctly).
The null hypothesis always contains the equal sign (=, , ).
Even the info
BUSINESS STATISTIC CHAPTER 08
Statistical inference is the process of using the statistics of a sample to estimate the parameters
of the population. It enables you to estimate unknown population characteristics such as mean
or a population proportion. T
BUSINESS STATISTIC CHAPTER 05
PROBABILITY DISTRIBUTION FOR A DISCRETE RANDOM VARIABLE
It is a mutually exclusive list of all possible numerical outcomes of the random variable with the
probability of occurrences associated with each outcome.
BUSINESS STATISTICS CHAPTER 05
Probability is a numerical value representing the chance that a particular event will occur.
There are 3 approaches to assigning a probability to an event:
o A priori classical probability: the probability of s
BUSINESS STATISTICS CHAPTER 01
Variables are characteristics of items or individuals
Data are the observed values of variables
Gender, Major and Age are characteristics of the sample of students
BUSINESS STATISTICS CHAPTER 03
= the sum of all sample values (X1+X2+.+Xn) / the number of sample values (n)
= sample mean
n = number of values or sample size
Xi = ith value of the variable X
As all the data play an equal role in the calculation, m
BUSINESS STATISTICS CHAPTER 06
CONTINUOUS PROBABILITY DISTRIBUTIONS
A continuous probability density function, f(x), is a mathematical expression that defines the
distribution of the values for a continuous random variable
THE NORMAL DISTRIBUTION