Interpreting evidence 2 Flashcards
what is a confidence interval
a range of values where there is a certain probability that the true value lies within the range
can indicate clinical significance
what is a chi squared test
used to examine difference within catergorical values
allows us to determine if the difference between the observed and expected numbers is different
what is a P value
the probability that the observed relationship occurred by chance
an arbitrary cut point is chosen
when the P value is below the cut point we reject the null hypothesis
what is a T test
used to determine whether two means are significantly different from each other
gives a probability that the difference would be found by change if the null hypothesis is true
e.g. the mean score from my experiment is no different from that found in a publication
what is the formula for the T test
t = (smple mean - hypothesized mean )/ SE of sample mean
what is correlation
measures the strength of relationship between two numerical variables
measured by the correlation coefficient (r) which varies between -1 and +1
a significant correlation coefficient is indicated by a P value in a statistical package
what is linear regression
used to predict relationship between independent and dependent variables
must be a linear relationship
an example of a model which estimates the regression coefficient (beta)
this has a confidence interval
P value for coefficient indicates the probability that the slope of the line = 0 (null hypothesis)
