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# Regression Analysis

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Hi! Can you help/guide me with a regression analysis on the data I've used this data for two papers. I was confused enough before but now????? My project has been comparing gasoline prices in the U.S. from 1975 to the mean average in 2006. Can you assist me in this final headache? I'm supposed to interpret the results of regression, state the limitations describe the significance. I need help.

H0: The mean price of gasoline in 2006 is the same as compared to gasoline prices in1975
H1: Gasoline prices are actually higher overall now as compared to 1975
_
Let x be the mean gasoline price now (\$2.68)
Let y be the mean gasoline price 30 year ago (\$1.80)
x - y ~ t with n1+n2 -1 degrees of freedom
s v ( 1/n1 + 1/n2 )
where s^2 = n1s1^2 + n2s2^2
n1+n2-1
s1^2 = 1 &#8721;( xi - x )^2
n1-1
Where n1 is the number of gasoline prices now
s2^2 = 1 &#8721;( yi - y )^2
n2-1
Where n2 is the number of gasoline prices in 1975
Conclusion: If calculated value is less than critical value accept H0 else reject Ho.

Appendix:

Historical Gas Prices
Year Price Per Gallon
1950 \$1.91
1955 \$1.85
1960 \$1.79
1965 \$1.68
1970 \$1.59
1975 \$1.80
1980 \$2.59
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1985 \$1.90
1990 \$1.51
1995 \$1.28
2001 \$1.66
2002 \$1.31
2003 \$1.52
2004 \$1.79
2005 \$2.28
2006 (so far) \$2.68
Source: U.S. DOE

Normal Hypothesis Two Sample Means and appears as follows:
Test of Normal Hypothesis
Two Sample Means

Input Data
X1_mean 2.68
X2_mean 1.8
s1_StdDev 0.44
s2_StdDev 0.44
n1_sample 1
n2_sample 1
Alpha 0.05
Calculated Value
z 1.414213562
Test for left tail
LftCrt_zVal #NAME?
Conclusion #NAME?
p-value 0.921350396
Test for Right Tail
RtCrt_zVal -1.644853627
Conclusion Reject Ho
p-value 0.078649604
Test for Two Tail
AbsCrt_zVal 1.959963985
Conclusion RejectHo
p-value 0.157299207

Step 1 of the 5 Step Process is: State the Null and Alternate Hypothesis
Ho: X1=X2 The mean price of gasoline today is equal to 1975
H1: X1>X2 The mean price of gasoline today is more than in 1975

Step 2 of the 5 Step Process is: Select a Level of significance
.05
Step 3 of the 5 Step Process is: Identify the Test Statistic
The test statistic as indicated above is the Test of Normal Hypothesis Two sample
Means.
Step 4 of the 5 Step Process is: Formulate a Decision Rule
Accept Ho if Critical value is more than calculated value
Step 5 of the 5 Step Process is: Decision
Reject Ho