Stats tests

Question 1

What are the 4 stats tests used

Answer 1

• Standard deviation
• T-test
• Chi-squared
• Spearman’s rank

Question 2

When is standard deviation used

Answer 2

Measure range of values around the mean

Question 3

When is T-test used

Answer 3

To find the difference between 2 means and see if the difference is significant

Question 4

When is Chi-squared used

Answer 4

Used to compare observed results with theoretical expected frequencies. The higher the X2 value the greater the difference.

Question 5

When is Spearman’s rank used

Answer 5

Used to see the strength of the correlation (association) between two sets of continuous data

Question 6

What does a smaller standard deviation mean

Answer 6

The smaller the standard deviation, the narrower is the range, which translate to a higher reproducibility.
The small standard deviation means the experimental values are clustered together tightly (higher precision).

Question 7

What does a larger standard deviation mean

Answer 7

The larger the standard deviation, the narrower the range, which means lower reproducibility. Large standard deviation means the experimental values are clustered together loosely (lower precision)

Question 8

What can be concluded if observed value from T-test was lower than critical value

Answer 8

• Results are due to chance

- Accept null hypothesis

Question 9

What can be concluded if observed value from T-test was higher than critical value

Answer 9

• Results are not due to chance

- Accept alternative hypothesis

Question 10

What is chi-squared often used for

Answer 10

genetics and fieldwork sampling.