The Essentials of Biostatistics for Physicians, Nurses, and Clinicians

98 CHAPTER 7 Correlation, Regression, and Logistic Regression

Subject

number

Systolic blood

pressure

Diastolic

blood pressure

25 145 81

26 151 83

27 134 85

28 178 99

29 128 73

30 147 78

31 146 80

32 160 91

33 173 79

34 143 87

35 152 69

36 137 85

37 146 83

38 162 83

39 158 77

40 152 86

41 152 93

42 106 67

43 147 79

4 4 1 1 1 7 1

45 149 83

46 137 77

47 136 84

48 132 79

Table 7.1

(Continued)

systolic blood pressure and Y is the corresponding diastolic blood pres-
sure taken at the same time. If the two variables are highly positively
correlated, the pattern of dots will closely resemble a straight line with
a little scatter.
In Figure 7.1 , we can perhaps visualize a straight line running
through the data but mainly what we observe is a tendency for the