maths skills Flashcards
how do you convert from nanometres to micrometres?
divide by 1000
how do you go from micrometres to nanometres?
times by 1000
how do you go from micrometres to millimetres?
divide by 1000
how do you go from millimetres to micrometres?
times by 1000
how do you work out the mean?
total/how many values there are
what is the mode?
the most common value
what is the median?
the middle value
what is standard form?
a x 10^n
what are logs used for?
converting large numbers onto a small scale
when do you use a chi square test?
to see whether there is a significant difference between the observed and expected results in an experiment
when do you use a student’s T test?
when looking at the difference between mean values
when do you use a Spearman’s rank correlation?
when looking at the association between measurements from the same sample- looks at whether variables are correlated
what is the null hypothesis?
when there is no significant difference between variables
when do you reject the null hypothesis?
when the data is significant- the test statistic is greater than the critical value
what happens when the probability is above 5%?
usually due to chance
