I am conducting a research on the influence of school administrators on teachers’ retention. I have collected data on this with likert-scaled (5 point 0-4) questionnaire from about 107 respondents. The two hypotheses for this research are:

1. There is no significant influence of school administrators on teachers’ retention.

2. The influence of school administrators on teachers’ retention does not differ significantly between private and public schools.

With my data, I have tested hypothesis 2 but I am having problem in testing the first hypothesis. The issues are:
a. How to determine an acceptable value for significant influence of school administrators on teachers’ retention so that it can be tested with One Sample T-Test.

b. If the above can't work, Then I need suggestions on how to go about it.

Thanks in anticipation of your assistance.