Study

 

Sampling Technique

 

Our population of interest were the students at NOHS, so, we first obtained a master list of all students at NOHS from Mrs. Caso. Using MINITAB (Calc->Random Data->Sample From Columns), we randomized 150 students from the list. Of the 150 students randomized, 72 were female and 78 were male. Additionally, our original sample contained 39 freshmen, 35 sophomores, 42 juniors, and 34 seniors. From the surveys we received back, we counted 45 females and 49 males, resulting in a total of 94 valid surveys. We also received 1 invalid survey (more than one answer was chosen for both questions) and 6 blank surveys.  

 

 

Sample Survey

PBHZ


Please only fill in one square for each question.

 

What car color do you prefer?



[] Silver/White [] Black [] Blue [] Other



What’s your gender?


[] Male [] Female

 

 

Significance Test

 

Type of Test:

 

We used "Cross Tabulation and Chi-Square" of MINITAB in order to perform a test of independence because we are attempting to observe if there is an association between gender and car color preference.

 

Check for Assumptions:

 

1. Expected cell counts above 5.

 

2. Random sample.

 

Significance Test:

 

Null hypothesis: There is no association between gender and car color preference; the two variables are independent.

 

Alternative hypothesis: There is an association between gender and car color preference; the two variables aren't independent.

 

Alpha: 0.05

TM000003.htm
Test Statistic:

Rows: Gender   Columns: Color

       Black   Blue  Other  Silver/White    All

F         17     11      7            10     45
       12.93  13.40  10.53          8.14  45.00

M         10     17     15             7     49
       14.07  14.60  11.47          8.86  49.00

All       27     28     22            17     94
       27.00  28.00  22.00         17.00  94.00

Cell Contents:      Count
                    Expected count

Pearson Chi-Square = 6.380, DF = 3, P-Value = 0.095
Likelihood Ratio Chi-Square = 6.470, DF = 3, P-Value = 0.091

X² = 6.380

P-Value = 0.095