3.3

Question 1

selection bias

Answer 1

selection of a sample in a non-random way so that it is not representative of the whole population

Question 2

standard deviation

Answer 2

shows how much variation or spread from the mean exists to question result validity

Question 3

statistically significant

Answer 3

unlikely due to chance alone

Question 4

t-test

Answer 4

statistical test that;s useful to determine whether two sets of data are significantly different enough to make a valid conclusion

Question 5

p-value

Answer 5

produced form a t-test, if value less than 0.05 the null hypothesis can be rejected this the treatment had an effect

Question 6

to ensure validity and reliability

Answer 6

experiment should address intended aim, test hypothesis, and have confounding factors controlled

Question 7

confidence and error bars

Answer 7

indicate reliability of data around a mean or percentage chance that the true mean lie somewhere along the bar