Assignment 1:
It is evident from the medical literature that mental anxiety has a close relationship with systolic blood pressure (SBP). As a biostatistician you want to compute this relationship and collected anxiety score and systolic blood pressure (SBP) from a random sample of 20 individuals. Here anxiety score is an independent variable (x) and SBP is a dependent variable mental anxiety (y). The following table shows the data.
Table: Anxiety score and systolic blood pressure
Individual idAnxiety score 0-100Systolic blood pressure 120-200 mmHg11012321312531512542512853513263913574014084514595515010651551165158127016013731601485165158517016881751790185189218519951902098195
1. From the above data set compute the correlation coefficient (r) (10 points)
Note: For using the formula of r, you need to calculate the covariance of (x, y), and variance of x and y.
2. Interpret the computed correlation coefficient (r) (5 points)
3. Compute the least square estimates of and (10 points)
Note: For calculation of and you need to calculate the mean and standard deviation (s) of x and y.
4. Interpret and (5 points)