In: Math
The median US salary is $50,700, according to US Census data. Using a one-sample
t-test, test to see if participant income (INC1) is different from the national average. Use a two-tailed test and an alpha level of 5%.
One-Sample Statistics
INCOME N=400 Mean=$47,112.92 Std. Deviation=$40,477.089 Std. Error Mean=$2,023.854
One-Sample Test
Test Value = 0
INCOME t=23.279 df=399 Sig. (2-tailed)=.000 Mean Difference=$47,112.920
95% Confidence Interval of the Difference
(lower)$43,134.17 (higher)$51,091.67
The median US salary is $50,700, according to US Census data. Using a one-sample
t-test, test to see if participant income (INC1) is different from the national average. Use a two-tailed test and an alpha level of 5%.
One-Sample Statistics
INCOME N=400 Mean=$47,112.92 Std. Deviation=$40,477.089 Std. Error Mean=$2,023.854

| 
 t Test for Hypothesis of the Mean  | 
|
| 
 Data  | 
|
| 
 Null Hypothesis m=  | 
 50700  | 
| 
 Level of Significance  | 
 0.05  | 
| 
 Sample Size  | 
 400  | 
| 
 Sample Mean  | 
 47112.92  | 
| 
 Sample Standard Deviation  | 
 40477.089  | 
| 
 Intermediate Calculations  | 
|
| 
 Standard Error of the Mean  | 
 2023.8545  | 
| 
 Degrees of Freedom  | 
 399  | 
| 
 t Test Statistic  | 
 -1.7724  | 
| 
 Two-Tail Test  | 
|
| 
 Lower Critical Value  | 
 -1.9659  | 
| 
 Upper Critical Value  | 
 1.9659  | 
| 
 p-Value  | 
 0.0771  | 
| 
 Do not reject the null hypothesis  | 
|
Calculated t= -1.7724, P=0.0771 which is > 0.05 level of significance.
Ho is not rejected.
Participant income is not significantly different from the national average
95% CI for difference
| 
 lower limit  | 
 -7565.83071  | 
| 
 Upper limit  | 
 391.6707062  |