P-value ( Probability value)

• Null hypothesis ( H₀) : There is no relationship between the two variables being studied.
• States results are due to chance.
• Null hypothesis assumes that whatever you are trying to prove didn’t happen.
• P-value is a number describing how likely it is true that your data would have occurred by random chance.
• P-value lies between 0 and 1.

Least squares method (LSM)

• It is a procedure hat minimizes the vertical deviations of plotted points surrounding a straight line.
• We are able to construct a best fitting straight line to the scatter diagram points and formulate a regression equation.

Unexplained variance

• 49% is due to fertilizer but what about 51%. It remains unexplained. Prediction hence is not perfect.
• For each value of x, we know the approx.. value of 4 but not the exact value.

Note:

i) The score that falls exactly on the regression line are called predicted scores.

ii) Line of best fit: It is a line that minimizes the distance of the actual score from the predicted score.