ST3123 Introduction of Statistics II
Review
A: Basic Concepts in Inferential Statistics
Population and Sample(simple random sample)
Population: all subjects of interest
Sample: part of population
Parameter ( ,
2
,
, p ) and statistic ( x , s 2 , s, p )
St
Selecting Appropriate Inferential Statistical Techniques
To begin our conversation about inferential statistics, the first step is to develop the ability to determine the
appropriate statistical technique to various situations. This decision that is a fun
Q-Mart is interested in comparing its male and female customers. Q-Mart would like to know if
the amount of money spent by its female charge customers differs, on average, from the amount
spent by its male charge customers.
To answer this question, an ana
Normal
Distribution
Normalization Distribution
Thenormal
distributionrefers
to
a
family
ofcontinuous probability distributionsdescribed by
the normal equation.
Normal equation.The
variableYis:
value
of
the
random
Y = cfw_ 1/[ * sqrt(2) ] * e-(x - )2/22
w
The form of the alternative hypothesis can be:
A.one or two-tailed
Question 2 of 20
1.0/ 1.0 Points
A manufacturer of flashlight batteries took a sample of 13 batteries from a days production and
used them continuously until they failed to work. The life
Basics of Statistics
Jarkko Isotalo
30
20
10
Std. Dev = 486.32
Mean = 3553.8
N = 120.00
0
2400.0
2800.0
2600.0
3200.0
3000.0
3600.0
3400.0
4000.0
3800.0
4400.0
4200.0
4800.0
4600.0
5000.0
Birthweights of children during years 1965-69
Time to Accelerate fr
Accepted characters:
Senior management of a consulting services firm is concerned about a growing decline in the
firms weekly number of billable hours. The firm expects each professional employee to spend
at least 40 hours per week on work. In an effort t
The Christian Respondent
Misuse of Statistics and Quotations by the Watchtower Society
( Number 44. Originally published June 21, 1988 )
The April 8, 1988 Awake! magazine addresses itself
to the question: "Are We in the Last Days?" Not
surprisingly, it co
Question 1 of 20
1.0/ 1.0 Points
If one tosses a coin enough times, the proportion of "heads" will approach 0.5. This is an
example of:
B.the Law of Large Numbers
Question 2 of 20
1.0/ 1.0 Points
If P(A) = P(A|B), then events A and B are said to be
C.inde
Study guide for the final exam:
Chapter 9:
1. Set up null and alternative hypothesis to compare two population means or proportions.
2. How to make inference for two population means or proportions based on a confidence
interval for the difference of two
Chapter 11 Simple Linear Regression
T-test, ANOVA: comparing means across groups or categories
Regression: relationships among numerical variables
11.1 Probabilistic Model
Deterministic Model: The model hypothesizes an exact relationship between the varia
Chapter 10 Analysis of variance (ANOVA) (comparing 3 or more population Means)
10.1 Elements of a designed experiment
1. The response variable (dependent variable) is the variable of interest to be measured in the experiment.
2. Factors are those variable
Chapter 9: Inferences based on two samples:
Confidence intervals and tests of hypotheses
9.1 The target parameter
2:
1
p1
2
1
difference between two population means
p2 : difference between two population proportions
2
2
: ratio of two population variance