In: Statistics and Probability
2. Below is some data on personality type (introverted or extroverted) and favourite colour. a) Run the appropriate test at a 5% significance level to determine if there is a relationship between these variables. (Be sure to state the hypotheses, test statistic, p-value, and conclusions.)
Run the standardized residuals. Provide the numbers and an interpretation.
| 
 Colours  | 
|||||
| 
 Red  | 
 Yellow  | 
 Green  | 
 Blue  | 
||
| 
 Introvert personality  | 
 20  | 
 6  | 
 30  | 
 44  | 
|
| 
 Extrovert personality  | 
 180  | 
 34  | 
 50  | 
 36  | 
|
Ho: given two variable are independent
H1: Given two variables are not independent
| Chi-Square Test of independence | |||||||
| Observed Frequencies | |||||||
| 0 | |||||||
| 0 | red | yellow | green | blue | Total | ||
| introvert | 20 | 6 | 30 | 44 | 100 | ||
| extrovert | 180 | 34 | 50 | 36 | 300 | ||
| Total | 200 | 40 | 80 | 80 | 400 | ||
| Expected frequency of a cell = sum of row*sum of column / total sum | |||||||
| Expected Frequencies | |||||||
| red | yellow | green | blue | Total | |||
| introvert | 200*100/400=50 | 40*100/400=10 | 80*100/400=20 | 80*100/400=20 | 100 | ||
| extrovert | 200*300/400=150 | 40*300/400=30 | 80*300/400=60 | 80*300/400=60 | 300 | ||
| Total | 200 | 40 | 80 | 80 | 400 | ||
| (fo-fe)^2/fe | |||||||
| introvert | 18.000 | 1.600 | 5.000 | 28.800 | |||
| extrovert | 6.000 | 0.533 | 1.667 | 9.600 | 
Chi-Square Test Statistic,χ² = Σ(fo-fe)^2/fe =  
71.200  
      
Level of Significance =   0.01  
Number of Rows =   2  
Number of Columns =   4  
Degrees of Freedom=(#row - 1)(#column -1) = (2- 1 ) * ( 4- 1 )
=   3  
      
p-Value =   0.0000   [Excel function:
=CHISQ.DIST.RT(χ²,df) ]
Decision:    p-value < α , Reject Ho  
conclusion: there is a relationship between these variables
........................
Please revert back in case of any doubt.
Please upvote. Thanks in advance.