Stats Tests

Question 1

When would you use correlation coefficient

Answer 1

When investigating the relationship between two variables

(Taking measurements)

Question 2

When would you use T test

Answer 2

When investigating a difference between two means

(Taking measurements)

Question 3

When would you use chi squared

Answer 3

When investigating the difference between two numbers of individuals

(Counting how many individuals in a category)

Question 4

What does it mean if the SDs do not overlap

Answer 4

There is a significant difference
Difference is not due to chance

Question 5

What does it mean if the SDs overlap

Answer 5

no significant difference
Difference is due to chance

Question 6

How do you write a null hypothesis eg investigating effect of antibiotics on lung cancer of mice

Answer 6

The antibiotics have no effect on the treatment of lung cancer in mice

Question 7

Describe how to use a stats test to find whether there is a correlation

Answer 7

1. Write a null hypothesis
2. Use CC and calculate test statistic
3. Look up in table to find critical value of P=0.05
4. Use figure to accept or reject null hypothesis

Question 8

what does it mean if the calculated value is more than or equal to the critical value (P=0.05)

Answer 8

• there is less than 5% probability that the results are due to chance
• difference is significant
• reject the null hypothesis

Question 9

what does it mean if the calculated value is less than the critical value (P=0.05)

Answer 9

• there is more than 5% probability that the results are due to chance
• difference is not significant
• accept the null hypothesis