Assume that a group of students wish to know whether there are more Toyotas, Hondas or fords in the parking lot at the college. You count the cars in the lot and find that there are 56 Toyotas, 71 Hondas and 83 fords. Note that you ignore all the other cars; they are not important for the information you desire) Let us make the hypothesis that there is no difference between the numbers of these cars; therefore your prediction is a 1:1:1 ratio. Determine whether there is a statistically significant difference between the number of these three kinds of cars in the parking lot.
Classes or Types of results O E (O-E) (O-E)² (O-E)²/E
Toyota 56 70 -14 196 2.8
Honda 71 70 1 1 .0142
Ford 83 70 13 169 2.414
1. How many degrees of freedom (df) are there in this experiment?
2. What is the value of X square?
3. What is the P value?
4. Is this significantly different from chance?
5. Is there a statistically significant difference in the number of Toyotas, Hondas, and fords in the parking lot?