Answer:
Predicted final score of Josh
Step-by-step explanation:
The linear regression relationship has been established between the final-exam score and the score on the first test
The relation ship is represented by a linear equation -
Where
score on the first test
final-exam score
Substituting the value of in above equation we will get -
Predicted final score of Josh
Answer:
As the sample size increases, the variability decreases.
Step-by-step explanation:
Variability is the measure of actual entries from mean. The less the deviations the less would be the variance.
For a sample of size n, we have by central limit theorem the mean of sample follows a normal distribution for random samples of large size.
X bar will have std deviation as
where s is the square root of variance of sample
Thus we find the variability denoted by std deviation is inversely proportion of square root of sample size.
Hence as sample size increases, std error decreases.
As the sample size increases, the variability decreases.