COMM104 Business Statistics I
Assignment I
Fall 2016
COMM 104 - Assignment I
Due date: October 5, 2016 (at the beginning of class)
1. The data in the table below give 18 measurements of a critical dimension for an
automobile part (measurements in centimet
1. The probability that the student will get all three questions correct is
2. The probability that the student will get exactly two questions correct is
since two questions will be answered correctly if and only if one of the sample space outcomes CCI, C
http:/digitalfirst.bfwpub.com/stats_applet/stats_applet_7_norm.html
5.6
Supposethattherandomvariablexhasauniformdistributionwithc=2andd=8.
a Writetheformulafortheprobabilitycurveofx,andwriteanintervalthatgivesthepossible
valuesofx.
a Graphtheprobabilitycu
Suppose that Best Buy has kept historical records of iPod sales during the last 100 weeks. These
records tell us that
1
No iPods have been sold in 3 (that is, 3/100 = .03) of the weeks.
1
One iPod has been sold in 20 (that is, .20) of the weeks.
1
Two iPo
Chapter 4: Discrete Random Variables
Random Variables
A random variable: A variable that assumes numerical values that are determined by the
outcome of an experiment
o
Discrete
o
Continuous
Discrete random variable: Possible values can be counted or liste
Comm 104: Chapter 11 Correlation Coefficient and Simple
Linear Regression Analysis
Covariance
The measure of the strength of the linear relationship between x and y is called the
covariance
o The sample covariance formula:
This is a point predictor of the
Comm 104: Business Statistics I
Jan. 6-25, 16
Chapter 2
The Shape of Distribution
To know what the population looks like, find the shape of its distribution
Picture the distribution graphically by any of the following methods:
o Stem-and-leaf display
o Fr
Comm 104: Business Statistics I
Jan. 6, 16
Chapter 1
Data
and Statistics
Statistics: the study of how to collect, summarize, and interpret data
Data: facts and figures from which conclusions can be drawn
Data Set: the data collected for a particular study
Comm 104: Chapter 9 Confidence Intervals
Confidence Intervals
Confidence interval for a population mean is an interval constructed around the sample mean so we
are reasonable sure that it contains the population mean
Any confidence interval is based on a
Chapter 5: Continuous Random Variable
Continuous Probability Distributions
A continuous random variable may assume any numerical value in one or more intervals
Use a continuous probability distribution to assign probabilities to intervals of values
o Many
Comm 104: Chapter 6 Sampling Distribution and Central
Limit Theorem
Sampling Variation
A sample statistic is a random variable whose value depends on which population items happen to
be included in the random sample.
Some samples may represent the populat
Comm 104 Chapter 3: Probability
Probability Concepts
An experiment is any process of observation with an uncertain outcome
The possible outcomes for an experiment are called the experimental outcomes
Probability is a measure of the chance that an experime