qualitative: pertaining to (that music was great)

quantitative: estimated (it's 20 degrees F colder today than yesterday)

Precision:

close imitation

check by repeating measurements

poor precision results from poor techinique

Accuracy:

correctness

check by using different methods

poor accuracy results from procedural or equipment flaws

Digits up to and including the first uncertain digit

• Counting significant digits                       

disappearing zeros hold the decimal point (not significant )       

Uncertainty in a measurement 

Ex: inserting a card halfway down the deck

The spread in the measurements 

(not the same as a bad measurement)

To reduce this- increase the # of measurements, making the average more reliable

Measurements evenly distributed about true value

poor precision

nonspecific causes

not reproducible

All measurements off in the one direction 

poor accuracy

definite causes

reproducible

premises lead to a conclusion for a particular case

advantage: with accurate premises, conclusion is right every time

disadvantage: conclusion contains no more information than premises

specific observation used to infer a general, widely applicable conclusion

advantage: get a lot of info from only one observation (leads to good hypotheses)

disadvantage: conclusion not guaranteed