ANOVA
Source of Variation |
Sum of squares |
Degrees of Freedom |
Mean Square |
F |
Between treatments |
90 |
3 |
||
Within treatments (Error) |
120 |
20 |
||
Total |
= (90 + 120) = 210 |
= (3+20) =23 |
Table 1: ANOVA table
The F-statistic is calculated as 5. The p-value for the F-statistic with 3 and 20 degrees of freedom is found to be 0.00951034. At 1% level of significance (α=0.01), as calculated p-value is less than 0.01, we decide to reject the null hypothesis.
Total number of groups = (degrees of freedom of between treatments) + 1 = (3+1) = 4
Hence, there are 4 groups in the question.
Total number of observations = (degrees of freedom of within treatment) + 1= (20+1) = 21
There are 21 observations in the question.
Coefficients |
Standard Error |
t Stat |
P-value |
Lower 95% |
Upper 95% |
|
Intercept |
136 |
13.76 |
9.881 |
0.000 |
104.2621 |
167.7379 |
Year (t) |
39.18 |
2.22 |
17.664 |
0.000 |
34.0668 |
44.29684 |
Table 2: Linear Regression Model
The simple linear regression, Y = a + b*X.
Here, the intercept (a) = 136, the slope (b) = 39.18.
According to the table 2, the estimated number of units sold by the auto manufacturer is:
Number of Units sold (‘000s) = 136 + 39.18*Year
It is the linear model of this analysis.
Thus, in the 11th (t=11) year, the number of units sold = (136+39.18*11) = 567 (‘000s).
Figure 1: Trend of the number of units sold by major auto manufacturer
The estimation of trend indicates that the number of units that can be sold by the auto manufacturer = 567000.
ANOVA |
|||||
df |
SS |
MS |
F |
Significance F |
|
Regression |
1 |
59.89145 |
59.89145 |
29.62415 |
0.002842 |
Residual |
5 |
10.10855 |
2.021711 |
||
Total |
6 |
70 |
Table 3: Linear Regression Model calculates F-statistic
The p-value of the F-statistic is calculated as 0.002842. Therefore, at 0.01 level of significance, there is statistically significant relationship between price and the number of flash drives sold.
Coefficients |
Standard Error |
t Stat |
P-value |
Lower 95% |
Upper 95% |
|
Intercept |
40.033 |
1.070 |
37.4309 |
0.0000 |
37.28362 |
42.78217 |
Units sold (y) |
-1.174 |
0.216 |
-5.4428 |
0.0028 |
-1.72897 |
-0.61971 |
Table 4: Linear Regression Model calculates t-statistic
The p-value is calculated as 0.002842. Therefore, at 0.01 level of significance, there is statistically significant relationship between price and the number of flash drives sold.
In a completely randomized experimental design, 14 experimental units were utilised for each of the five levels of factor (5 treatments). We executed ANOVA table.
Source of Variation |
Sum of Squares |
Degrees of Freedom |
Mean Square |
F |
Between treatments |
= (4*800) = 3200 |
= (5 – 1) = 4 |
800.00 |
|
Within treatments (Error) |
= (10600 – 3200) = 7400 |
= (14 – 1) = 13 |
||
Total |
10600 |
17 |
Table 5: ANOVA Table
ANOVA |
||||||
Source of Variation |
SS |
df |
MS |
F |
P-value |
F crit |
Between Groups |
324 |
2 |
162 |
40.500 |
0.000 |
4.256 |
Within Groups |
36 |
9 |
4 |
|||
Total |
360 |
11 |
Table 6: ANOVA Table
The hypotheses are:
Null Hypothesis (H0): The average sales of the three stores are equal.
Alternate Hypothesis (HA): There exists at least one inequality of average sales of the stores.
At 5% level of statistical significance, we can reject the Null Hypothesis for its p-value (0.000<0.05). Hence, the mean values of sales of the three stores are not equal. There exist significant differences in the mean sales of the three stores.
The hypotheses are-
Null Hypothesis (H0): The mean values of sales of the three boxes are equal.
Alternate Hypothesis (HA): There exists at least one equality in mean sales of the boxes.
ANOVA |
||||||
Source of Variation |
SS |
df |
MS |
F |
P-value |
F-crit |
Between Groups |
24467.2 |
2 |
12233.6000 |
53.7111 |
0.000 |
3.8853 |
Within Groups |
2733.2 |
12 |
227.7667 |
|||
Total |
27200.4 |
14 |
Linear Regression
Table 7: ANOVA Table
The p-value is calculated as 0.0. Therefore, at 0.05 level of statistical significance, we can reject the Null Hypothesis of equality of mean values of sales. Therefore, the sales of the three boxes are unequal.
Brand A |
Brand B |
Brand C |
|
Average Mileage |
37 |
38 |
33 |
Sample Variance |
3 |
4 |
2 |
Count |
10 |
10 |
10 |
Table 8: Descriptive statistics table
The total average = [(37*10) + (38*10) + (33*10)] = [370 + 380 + 330] = 1080
The total average mileage =
Thus, SSBetween Groups (SSB) = [10*(37 – 36)2+10*(38 – 36)2+10*(33 – 36)2] = 140
SSError (SSE) = [(10*3) + (10*4) + (10*2)] = 90
ANOVA |
||||
Source of Variation |
SS |
df |
MS |
F |
Between Groups |
140 |
2 |
||
Within Groups |
90 |
=(29 – 2) = 27 |
||
Total |
210 |
29 |
Table 9: ANOVA Table
F-critical calculated from F-table with (2, 27) degrees of freedom at 5% level of significance is 0.00000313.
As, F-value (21.02)> F-critical (0.00000313), at 5% level of significance, there exists sufficient evidence to reject Null Hypothesis. Therefore, there is a statistically significant variability in the average mileage of the tyres.
Day |
Tips |
Simple Moving average |
1 |
18 |
|
2 |
22 |
19 |
3 |
17 |
19 |
4 |
18 |
21 |
5 |
28 |
22 |
6 |
20 |
20 |
7 |
12 |
Table 10: Moving Average Table
Days (x) |
Forecast (Y) |
Y’ |
(Y-Y’) |
(Y-Y’)2 |
1 |
19 |
19.2 |
-0.2 |
0.04 |
2 |
19 |
19.7 |
-0.7 |
0.49 |
3 |
21 |
20.2 |
0.8 |
0.64 |
4 |
22 |
20.7 |
1.3 |
1.69 |
5 |
20 |
21.2 |
-1.2 |
1.44 |
0.00 |
0.86 |
Table 11: Forecasting Table
The mean square error of the forecast is calculated as 0.86.
The mean absolute deviation of the forecast is calculated as 0.00.
Source of Variation |
Degrees of Freedom |
Sum of Squares (SS) |
Mean Square (MSS) |
F-statistic |
Regression |
4 |
283940.60 |
70985.15 |
2.055 |
Error |
18 |
621735.14 |
34540.84 |
|
Total |
22 |
905675.74 (TSS) |
Table 12: ANOVA Table
The coefficient of determination = (
From the linear regression model, it can be inferred that 7.84% of the variability in sales of “Very Fresh Juice Company” could be explained by the independent variables – “price per unit”, “competitor’s price”, “advertising” and “type of container.”
Significance value of F-statistic can be found in MS-Excel by the excel function FDIST(2.055,4,18). According to the p-value (α=0.05), F-statistic with degrees of freedom 4 and 18 is 0.12942. As, 0.12942>0.05, at 0.05 level of significance, we do not have sufficient evidence to reject Null Hypothesis. Therefore, the model statistically is insignificant.
The total sample size = (Total degrees of freedom +1) = (22+1) = 23.
ANOVA |
|||||
df |
SS |
MS |
F |
Significance F |
|
Regression |
2 |
118.8474369 |
59.4237 |
40.9216 |
0.000 |
Residual |
9 |
13.0692 |
1.4521 |
||
Total |
11 |
131.9166667 |
|||
Coefficients |
Standard Error |
t Stat |
P-value |
||
Intercept |
118.5059 |
33.5753 |
3.5296 |
0.0064 |
|
Number of shares sold (in ’00s) (x1) |
-0.0163 |
0.0315 |
-0.5171 |
0.6176 |
|
New York Stock Exchange (x2) |
-1.5726 |
0.3590 |
-4.3807 |
0.0018 |
Table 13: ANOVA Table of Regression Model
The price of the stock can be predicted from the linear regression provided trend equation-
y = 118.5059 – 0.0163*x1 – 1.5726*x2
From the linear regression equation, it can be said that:
- For every 100 stocks of company sold the price of Rawlon Inc. stock would decrease by 0.0163 and vice versa.
- For every million enhance in exchange of the New York Stock Exchange the price of Rawlon Inc. Stock would reduce by 1.5726 and vice versa.
- For, zero amount of sold price of both Rawlon Inc. and New York Stock Exchange, the Inc. Stock is found to be 118.5059.
At 0.05 level of significance, the volume of exchange of New York stock exchange is statistically significant (as p-value = 0.0018< 0.05).
The p-value is calculated as 0.6176 (>0.05). Therefore, at 0.05 level of significance, the number of shares sold by Rawlon Inc. is not statistically significant.
For 94500 stocks sold and 16 million the volume of exchange on the New York Stock Exchange, the price of the stock (Inc. stock) would be:
y = [118.5059 – (0.0163*x1) – (1.5726*x2)]
= [118.5059 – (0.0163*945) – (1.5726*16)]
= 77.95