Excel T Test

The t test is a statistics test generally used to test whether means of populations are different. In the t test, a t value is calculated based upon the difference in the means and variances of the two populations. The greater the t value, the more certain it is that the means are different.The t value can be generally described as follows:

t value = (Difference between the group means) / (Variability of the groups)

The t value is a specific point on the x-axis in the t distribution(student’s t distribution). If this t value falls outside the region of required certainty, it can be stated that the two means are probably different. If this t value falls within the region of required certainty, it cannot be stated that the two means are probably different. 

The required region of certainty depends upon the degree of certainty required in the test. If 95% certainty is required, then the required region of certainty consists of 95% of the area under the student’s t distribution. The outer 5% is the region of uncertainty. This is also referred to as α (alpha) or the degree of significance. If the t value is large enough to be located all the way out on the x-axis in the 5% region of uncertainty, it can be stated within 95% certainty that the two means are different. 
  For more information on t test please click here

What I Did

The purpose of  this assignment, was to formulate and test a hypothesis 2 samples using a t test function
Here the categorical independent variable is gender  male/female. The continuous dependent variable is NAEP 2011 4th Grade state reading averages. The hypothesis is stated, then the null hypothesis. Our decision after doing our statistical analysis is to accept or reject the null hypothesis.

Research Question was : Does student’s gender impact 4th grade reading scores performance?

Hypothesis-

H0: (Null Hypothesis)
There is a difference between the male and female scores.
Gender plays a role in the reading scores of 4th graders.
H1: There is no difference.



I went back to the NCES data from the previous assignment and performed a t test to see if there is a difference between the reading scores of 4th grade males and females.

Conclusion

Since the p value is 1.60684E-07 which is greater than 0.05, we reject the null hypothesis and say that “we have a 95% degree of confidence that gender is not a factor in 4th grade reading scores of male and female students.”

To access my T -test data please click here

Future Application

Research topic question for my future class will be: Does student's attendance of summer school during the holidays affect academic grades positively.
Research group : Students in my 9th grade Algebra class
Dependent Variable :Students grades
Independent Variable:Summer School Classes
Null Hypothesis:There is no statistically significant difference in students grades after attending summer school
Hypothesis : Attending summer school during the holidays affects students grades positively.