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Heart Rate
Some of the ‘Heart Rate’ Data
Some of the ‘Heart Rate’ Data
• Take a look at the
data so you have
some ideas to start
with.
• Get an idea about
the type of question
you might like to
answer.
Possible questions
• Is there a relationship between the
number of beats/min before and after the
students had stepped up and down on a
block of a fixed height?
• How does the heart rate change after
exercising?
Start with calculating the statistics on
Excel.
REST ING
Mean
80
Median
81
Mode
69
Range
36
Minimum
60
Maximum
96
Sum
2400
Count
30
LQ
72.75
UQ
87
IQ Range
14.25
FINA L
Mean
106.3
Median
99
Mode
99
Range
78
Minimum
75
Maximum
153
Sum
3189
Count
30
LQ
93
UQ
119.25
IQ Range
26.25
Comment on the statistics
REST ING
Mean
80
Median
81
Mode
69
Range
36
Minimum
60
Maximum
96
Sum
2400
Count
30
LQ
72.75
UQ
87
IQ Range 14.25
FINA L
Mean
106.3
Median
99
Mode
99
Range
78
Minimum
75
Maximum
153
Sum
3189
Count
30
LQ
93
UQ
119.25
IQ Range 26.25
• Comment on the
Central Tendencies:
Comment on the statistics
REST ING
Mean
80
Median
81
Mode
69
Range
36
Minimum
60
Maximum
96
Sum
2400
Count
30
LQ
72.75
UQ
87
IQ Range 14.25
FINA L
Mean
106.3
Median
99
Mode
99
Range
78
Minimum
75
Maximum
153
Sum
3189
Count
30
LQ
93
UQ
119.25
IQ Range 26.25
• The mean increased by
26.3 beats/min but the
median increased by 18
beats/min. This
suggests that there are
extreme values and the
median would be a
better measurement an
‘average’ increase.
• The mode has little
meaning in this context.
Comment on the statistics
REST ING
Mean
80
Median
81
Mode
69
Range
36
Minimum
60
Maximum
96
Sum
2400
Count
30
LQ
72.75
UQ
87
IQ Range 14.25
FINA L
Mean
106.3
Median
99
Mode
99
Range
78
Minimum
75
Maximum
153
Sum
3189
Count
30
LQ
93
UQ
119.25
IQ Range 26.25
• Now comment on the
spread.
Comment on the statistics
REST ING
Mean
80
Median
81
Mode
69
Range
36
Minimum
60
Maximum
96
Sum
2400
Count
30
LQ
72.75
UQ
87
IQ Range 14.25
FINA L
Mean
106.3
Median
99
Mode
99
Range
78
Minimum
75
Maximum
153
Sum
3189
Count
30
LQ
93
UQ
119.25
IQ Range 26.25
• The range of values for
the final increased by
42 (probably due to
extreme values).
• The IQR would give a
better measure of
spread as the increase
was only 12.
Appropriate graphs
• If we are comparing values, a box and
whisker plot would show this.
Box and Whisker Plot
Final
Resting
20
40
60
80
100
Heart rate (Beats/min)
120
140
160
Comments
Box and Whisker Plot
Final
Resting
20
40
60
80
100
Heart rate (Beats/min)
120
140
160
• These plots show that
there has been a
marked increase in
heart rate after the
exercise.
• All three measures:
Median, LQ and UQ
have increased.
• As the boxes do not
overlap, the increase
can be considered to be
significant.
Comments
• Both the range and
interquartile range have
increased showing an
increase in the spread
of the data.
Box and Whisker Plot
Final
Resting
20
40
60
80
100
Heart rate (Beats/min)
120
140
160
If you are looking for a relationship between variables a
scatterplot shows the relationship.
Scatterplot of heart rate before and after exercise
Final Heart rate (Beats/min)
160
150
y = 1.1235x + 16.422
R2 = 0.2772
140
130
120
110
100
90
80
70
60
50
60
70
80
Resting Heart rate (Beats/min)
90
100
If you are looking for a relationship between variables a
scatterplot shows the relationship.
Scatterplot of heart rate before and after exercise
Final Heart rate (Beats/min)
160
150
y = 1.1235x + 16.422
R2 = 0.2772
140
130
120
110
100
90
80
70
60
50
60
70
80
Resting Heart rate (Beats/min)
90
100
• The relationship
between resting and
final heart rate is a
positive linear
relationship.
• The gradient of the line
suggests that we could
expect on average a
1.12 beats/min increase
in heart rate for every 1
beat/min increase in the
resting heart rate.
Evaluation
• 30 volunteers were found from among the
student’s friends.
• Because the survey was done using volunteers, it
may not represent the population as a whole.
• The student’s friends may be more or less
physically able than the general student
population.