How Science Works Flashcards
(21 cards)
Why is a large sample size important?
Large sample size so results are representative
Why is a long study important?
Long study so can see effect of X over time
Why is using a control important?
Control used so comparison can be made
Why are mean and standard deviation (SD) used?
Mean & SD so significant differences can be determined
Why is it important to use a statistically valid scale for pain?
Pain perception is subjective
Why does pain perception subjectivity matter?
Pain threshold varies between individuals
What does a valid scale ensure about pain differences recorded?
Differences are statistically significant
What does statistical significance mean here?
Differences are not due to chance
Why else use a statistically valid scale?
For valid comparison between patients
What is a limitation of a small sample size?
Not representative of whole population
Why is sampling only males a limitation?
Females may respond differently to treatment
What is a limitation of testing only in a lab?
In the wild may produce different data patterns
What is a limitation of testing only one species?
Might not be true for all species
What is the limitation of no statistical test?
Differences could be due to chance
What is a limitation of subjective data?
Some people may have lied or misreported
What is a null hypothesis?
[X] will have no effect on [Y]
Give an example of a null hypothesis with temperature.
Temperature will have no effect on rate of reaction
Give an example null hypothesis for correlation.
There will be no correlation between age and weight
Give an example null hypothesis for expected ratio.
No difference between observed and expected ratio of 3:1 brown eyes to blue eyes
Why is a log scale used to record number of cells/bacteria?
Large range/difference/increase in numbers
What kind of increase is usually recorded with cell/bacteria numbers?
Exponential increase
