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Lab section number
S'IAT/MATH 212 (Sections 1 6. 1 31 5)
LAB ASSIGNMENT
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1
Introduction to the lab and to MyStatlab. (No food, no drinks, have fun.)
I. If you have not already done so, register and log in to MyStatlab (MyMathlab).
Your
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Laboratory Section
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Review and discuss last week's laboratory.
11.
Individual
work
For this section you are to work by yourself, or with your partner.
For each variable in the following set of var
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Lab
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Stat/Ncfw_ath 212
Sections 16, 1315
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Discuss previous lab, homen ork, and other questions.
Form teams of 2 w 3 to lvork on this lab.
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Purpose: To conduci a significance test and
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STATA4ATH212
Sept. 13

Sept. 17
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LAB
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Questions and Answers (previous lab, current homework)
ii.
In many situations. peopie neeci the probabiiity that a certain evenr wiii occur. For exampie. a p
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HOMEWORK 3
l. In poor countiies the grorith of children can be an impofiant indicator ol gcneral levels of ntrtrition and
health. Data in the paper 'Thc Osteologicatr Paraclox: Pr
. lnClass Regression Problem
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 3. Find the average for x and the average for y
N 1+5 A 31? ,
/\" '37.? 2. q 3~ T Li's (a
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b. Find pearson correlation coefficient ( r)
m
67.37
218. 00
n 2x3 ixi ('awm
Z Test for Differences in Two Proportions
Data
Hypothesized Difference
Level of Significance
Group 1
Number of Successes
Sample Size
Group 2
Number of Successes
Sample Size
Intermediate Calculations
Group 1 Proportion
Group 2 Proportion
Difference in Two
Z Test of Hypothesis for the Proportion
Data
Null Hypothesis
p=
Level of Significance
Number of Items of Interest
Sample Size
Intermediate Calculations
Sample Proportion
Standard Error
Z Test Statistic
0.3
0.05
320
1000
0.3200
0.0145
1.3801
TwoTail Test
STAT212
Practice Questions for Exam 2
1. An investigator claims that = the average weight of passengers flying on small planes exceeds the FAA guideline of
average total weight of 185 pounds (passenger weight including shoes, clothes, and carryon). Suppo
B Bus 215 B
Answer Correction
#1 The variance is computed as the average squared deviation of each number from
its mean. The variance is closer to standard deviation, but stand deviation is not
squared, and variance is squared, therefore the standard devi
Z Test for the Mean
Data
Null Hypothesis
m =
Level of Significance
Population Standard Deviation
Sample Size
Sample Mean
Intermediate Calculations
Standard Error of the Mean
Z Test Statistic
368
0.05
15
25
372.5
3
1.5
TwoTail Test
Lower Critical Value
1
Variability in a Distribution
Data
Mean
Standard Deviation
2.06
0.02
Results
1 standard deviations
2 standard deviations
3 standard deviations
% of Values Found in Intervals Around the Mean
Range
2.04
2.02
2.00
2.08
2.10
2.12
Chebyshev Rule (any
distribut
t Test for the Hypothesis of the Mean
Data
Null Hypothesis
m=
Level of Significance
Sample Size
Sample Mean
Sample Standard Deviation
Intermediate Calculations
Standard Error of the Mean
Degrees of Freedom
t Test Statistic
120
0.05
12
112.85
20.8
6.0044
1
Grizelda Samano
Nov 16, 2016
Stats 212 Lab 13
INTRODUCTION
In order to identify if it is cheaper to buy groceries at a Safeway store vs. a
WalMart store, a comparison of two population means using dependent samples
(paired ttest) was used. The paired t
ConceptsforExam2
*Thislistismeanttohelpguideyourstudying.ItmayNOTbeanexhaustivelist.*
NormalDistribution(more in context with distribution of sample mean and sample proportion)
Beabletocalculateprobabilitiesforanormalrandomvariableusingthenormaltable
Be
Normal Probabilities
Common Data
Mean
Standard Deviation
7
6
Probability for X <=
X Value
Z Value
P(X<=7)
7
0
0.5000
Probability for X >
X Value
Z Value
P(X>9)
9
0.33333333
0.3694
Probability for X<7 or X >9
P(X<7 or X >9)
0.8694
Probability for a Range
F
Paired t Test
Data
Hypothesized Mean Diff.
Level of Significance
0
0.05
Intermediate Calculations
Sample Size
DBar
degrees of freedom
SD
Standard Error
t Test Statistic
TwoTailed Test
Lower Critical Value
Upper Critical Value
pValue
Reject the null hypo
"Dow Dogs" Population
Parameters
1YrReturn
Mean
7.6570
Variance
84.8352
Standard Deviation
9.2106
"Dow Dogs" Population
Parameters
1YrReturn
Mean
7.6570
Variance
84.8352
Standard Deviation
9.2106
Stock
AT&T
Verizon
Merck
Pfizer
GE
DuPont
Johnson & Johns
For the Mean Sales Invoice Amount
Data
Population Standard Deviation
Sampling Error
Confidence Level
Intemediate Calculations
Z Value
Calculated Sample Size
25
5
95%
1.9600
96.0365
Result
Sample Size Needed
97
For the Mean Sales Invoice Amount
Data
Popul
For the Proportion of InError Sales Invoices
Data
Estimate of True Proportion
Sampling Error
Confidence Level
Intermediate Calculations
Z Value
Calculated Sample Size
0.15
0.07
95%
1.9600
99.9563
Result
Sample Size Needed
100
For the Proportion of InEr
For most applicationsThe units for the variance are always squared this is why the standard devia
The median selling price of new homes in a state in 2002 was $112,800, $40,000 is the most plausible
0.55
0.57
0.57
0.68
0.71
0.78
0.86
0.89
0.91
0.97
1.14
1
Selects 140 dealerships randomly, surveys all customers cluster
Stratified number of individuals sampled from each stratum should be proportional to the size of the
strata in the population. Grouped, then obtain random sample from each group. 10 compani
Biology 251
6 October 2009
Exam Two
FORM W
PRINT YOUR NAME AND ID NUMBER in the space that is provided on the answer sheet, and then blacken
the letter boxes below the corresponding letters of your name and ID number. You will have 4 points
deducted if yo
Spencer Lane
Professor Alldredge
Stats 212
8 December 2008
Project 2
College is proven to be one of the most stressful and hard times in a persons life. It is a big shock
when a person goes from high school to college. This change can affect can cause man
Difference Sample Mean
1  2
Std. Err.
DF
TStat
0.2175 0.10241867 78 2.1236362
Pvalue
0.0369
+
Summary statistics:
Colum
n Mean Variance
n
var1
40
var2
40
Std. Dev.
Std. Err.
Media Rang
Min Max Q1 Q3
n
e
2.992 0.2617371
0.0808914
0.5116026
5
7
7
3
2
2
Hypothesis test results:
1 : mean of var1
2 : mean of var2
1  2 : mean difference
H0 : 1  2 = 0
HA : 1  2 0
(with pooled variances)
Difference Sample Mean
1  2
Std. Err.
DF
TStat
0.2175 0.10241867 78 2.1236362
Summary statistics:
Colum
n Mean Varia