Errors in Measurements

Errors in Measurements

1. Types of Errors

   • Systematic Error
     • Affect accuracy
     • Sources of errors
       • Instrument not calibrated
       • Faulty apparatus (zero error)
       • Procedure/method incorrect
       • Predictable
     • Methods to identify/ eliiminate this ?
       • Calibrating equipment for zero error
       • Improving experimental design
       • Repeating experiment using different instruments
   • Random Error
     • Affect precision
     • Sources of Errors
       • Fluctuation reading (e.g: Burette/pipette)
       • Small sample size/trials
       • Statistical fluctuation of measurement
       • Unpredictable
       • Parallax error
     • Ways to reduce/ prevent this ?
       • increase number of reading
       • Increase sample size/ trials
       • Using statistical mean

2. Characteristic of Measurement

   • Accuracy
     • Measurement value close to correct value
   • Precision
     • Measurement value close to each other

3. Impact of errors in experimental results

   • Experimental bias
   • Affect analysis and results interpretation