In: Statistics and Probability
Use a one-way ANOVA test to study the price difference between cruelty-free products and those tested on animals
| Products | Cruelty free | Tested on animals | 
| Foundation | 39 | 43 | 
| Concealer | 29 | 28 | 
| Lipstick | 19 | 22 | 
| Serum | 54 | 41 | 
| Perfume mist | 12 | 13.07 | 
| Body oil | 26 | 32 | 
| Soap | 12 | 15 | 
These are a few products from well known brands and can be found easily online.
Null hypo: There is no significance difference between animal tested and cruelty free products prices.
VS
Alternative hypo: There is significance difference between animal tested and cruelty free products prices.
We will conduct the test at 0.05 level of significance.
| ANOVA | ||||||
| Source of Variation | SS | df | MS (SS/df) | F (SSb/ SSr) | 
P-value (P  >
F) | 
F crit  ![]()  | 
| Between Groups | 0.673207 | 1 (k - 1) | 0.673207 | 0.003625 | 0.953 | 4.75 | 
| Within Groups | 2228.801 | 12 (n - k) | 185.7334 | |||
| Total | 2229.475 | 13 | 
As you can see that p-value > 0.05 and also Test stat (F) < critical (F crit )
WE don't reject the null hypothesis and conclude that there is no significant difference between cruelty free and animal tested product prices at 0.05 level of significance.
This is ANOVA - Single Factor. We first need to find the
 and 
.
They are 'Total variance' and 'Variance in between the treatments'
respectively.
We know

 = 
Grand total = 385.07 Sum of individual squares = 12820.82
 = 2229.48
 = 
Note: We have to separately sum 
 for all the treatment.
= 
= 10592.7
 =0.673
2228.80
We can also use excel data analysis function
Steps: