In: Statistics and Probability
HW 9: Linear Regression and Correlation Analysis
INSTRUCTIONS: Please modify the Excel sheet attached to complete this assignment. Turn in the following work including: 1) written formulas, 2) values from Excel plugged into formulas, and 3) final answer.
Scenario: A graduate student has administered a pro-inflammatory substance, lipopolysaccharide (LPS), to rats in the form of a pill (several doses – 0 mg or placebo, 1.25 mg, 2.5 mg, 5.0 mg, and 10 mg). She then determines the blood concentration of a particular protein that is thought to be upregulated due to LPS called Inflammo using ELISA. Find the linear model and the correlation coefficient of the experimental data on Blackboard labeled “HW9 Raw Data”.
LPS delivered (mg) | Inflammo (ug/mL) |
10 | 2.234 |
5 | 1.198 |
2.5 | 0.735 |
1.25 | 0.411 |
0 | 0.105 |
10 | 2.337 |
5 | 1.201 |
2.5 | 0.805 |
1.25 | 0.431 |
0 | 0.088 |
10 | 2.115 |
5 | 1.275 |
2.5 | 0.881 |
1.25 | 0.249 |
0 | 0.101 |
10 | 2.176 |
5 | 1.303 |
2.5 | 0.691 |
1.25 | 0.383 |
0 | 0.089 |
(10pts)Equation for Linear Model:
(10pts)Correlation Coefficient:
(10pts)Does the linear model describe the relationship between LPS and Inflammotin concentration well?
(10pts)If so, what type of correlation exists between LPS dosage and Inflammo concentration?
Equations/formulas (30 pts)(Attach work):
we will perform analysis using excel and steps are
1) Enter data into excel
2) click on Data tab Then click On Data Analysis select Regression
Now in output range select dependent variable that is Inflammo (ug/mL
and for input range select range of LPS delivered (mg)
click on labels if your selecting data including labels.
click on ok
It will give following output
SUMMARY OUTPUT | ||||||
Regression Statistics | ||||||
Multiple R | 0.9933 | |||||
R Square | 0.9866 | |||||
Adjusted R Square | 0.9858 | |||||
Standard Error | 0.0915 | |||||
Observations | 20.0000 | |||||
ANOVA | ||||||
df | SS | MS | F | Significance F | ||
Regression | 1.0000 | 11.0660 | 11.0660 | 1321.8489 | 0.0000 | |
Residual | 18.0000 | 0.1507 | 0.0084 | |||
Total | 19.0000 | 11.2167 | ||||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | |
Intercept | 0.1514 | 0.0298 | 5.0777 | 0.0001 | 0.0888 | 0.2141 |
LPS delivered (mg) | 0.2104 | 0.0058 | 36.3572 | 0.0000 | 0.1982 | 0.2225 |
Equation for Linear Model
Inflammo (ug/mL) =0.1514+0.2104*LPS delivered (mg)
Correlation Coefficient: 0.9933
Does the linear model describe the relationship between LPS and Inflammotin concentration well?
From Anova table
p-value = 0 < 0.05 level of significance so we reject the null hypothesis and conclude that relationship between LPS and Inflammotin concentration is significant.
If so, what type of correlation exists between LPS dosage and Inflammo concentration
Correlation Coefficient: 0.9933
so their is perfect positive correlation between LPS dosage and Inflammo concentration