Sub lesson - student T-tests

Question 1

Use of the student’s t-test?

Answer 1

Statistical test used to determine if there is a significant difference between the mean values of a particular variable across two populations.

Question 2

Conditions for use of a student’s t-test?

Answer 2

• Data must be continuous and normally distributed
• Variances of the populations should be equal
• The samples must be independent of each other.

Question 3

Conducting a t-test:

Answer 3

1. State the null hypothesis
   This assumes there is no significant difference between the means of the datasets.
2. Calculate the t statistic using the t-test formula (provided in exams)
3. Calculate the degrees of freedom
   df in a t-test = n1 + n2 - 2
4. Compare the statistical t statistic against a critical value.
   Critical value is determined by the degrees of freedom and the chosen significance level (p = 0.05). We will be provided with table of critical values in exam.

Results:
- If t statistic is greater than critical value:
- Reject the null hypothesis
- Suggests that the means are significantly different.
- If the t statistic is less than the critical value:
- Accept the null hypothesis
- Suggests that there is no significant difference between means, and any difference is just due to chance.

Question 4

x with hat

Answer 4

Mean

Question 5

o thing

Answer 5

standard deviation

Question 6

n

Answer 6

sample size