Repeating an experiment will make our results more...
Why does repeating an experiment make results more reliable?
because it is easier to spot anomalies (mistakes)
Circle the anomaly on this graph
What is an anomaly?
A result that does not follow the pattern of the other results
What can cause anomalies?
Human error (mistakes when measuring)
Different people measuring
What is the independent variable in this experiment?
The type of worm (the left hand column heading)
What is the dependent variable in this experiment?
The number of worms left (the right hand column heading)
How has the mean number of red worms been calculated?
Add the number of red worms eaten on each day and divide by how many days there are.
Which type of graph will you plot for these results?
Bar chart because the independent variable is a label (colour of worm)
Which column will you put along the x axis?
Colour of worm (independent variable always goes on X axis)
Which column will you put along the Y axis?
Number of worms left (dependent variable always goes on Y axis)
Would you plot the results from every day?
No, only plot the mean values
Why do we only plot the mean values?
Becuase they are more reliable as they take into account all of the repeat values.