general exam tips Flashcards
why do the standard deviations differ
different groups have different spreads of data around the mean
what does it mean when the standard deviations overlap
-the data is not significant - so there is no significant difference in the values
what does it mean when the standard deviations dont overlap
-the data is significant - there is a significant difference between the means
estimate the value of the correlation coeffeicent of a postive correlation
-close to +1
-so between 0.5 and 0.99
estimate the value of a negative correlation coefficient
-close to 0
-0 to 0.5
sugegst some considerations that should have been taken into account to ensure that the study was reliable
-large sample size
-chose ppl randomly
-chose ppl with a range of ages
-equal number of males and females
-repeat readings/measurements
why do the shapes/size in the image appear to be different comapred to each other and in real life
shape- tissue has been treated/killed/damaged
size-cut through different sections/planes
patients recorded the intensity of pain, suggest two reasons why it was
important to use a statistically valid scale.
- (Sensation of) pain is subjective
OR
Pain sensitivity/threshold/tolerance varies; - To ensure that differences (in pain detection)
were (statistically) significant
OR
For (valid) comparison;
Suggest what the scientist should do to ensure that he has removed all the water from
the sample.
- Weigh and heat;
- (Until) mass is constant;