EXSC 520
CASE STUDY: CORRELATION AND BIVARIATE REGRESSION TEMPLATE
I. Correlation
Research question: “Is mean heart rate during exercise correlate to body weight?”
Assumptions Testing
1. Data level of measurement – what was the level of measurement for the data used in this case
study (ratio, interval, etc.)?
The data level measurement for data used in this case is ratio. The four types of levels of
measurement are nominal, ordinal, interval, and ratio. All of these types of levels can either
be categorized, ranked, or infer equal intervals between data; however, ratio level is the only
level that can do all and have a true zero measurement. Both heart rate and body weight are
able to be categorized, ranked, have equal intervals between neighboring measurements and
have a true zero measurement, leaving ratio level being used for the case study
2. Would the amount of skewness and kurtosis in these variables affect the analysis? How do
you know? Give numerical values to support your conclusion.
For the amount of skewness or kurtosis to affect the analysis, the number must be below
-1.96 or above 1.96. Any value that comes between these two numbers is indicative of the
lack of skewness or kurtosis. The HR skewness had a calculated value of 0.7148, for HR
kurtosis, the calculated value is -0.5232. Both of these values fall in acceptable range, so
there is neither skewness or kurtosis for the heart rate. For BW skewness, the calculated
value was 2.625, for BW kurtosis, the calculated value is 1.6331. For body weight, both
skewness and kurtosis calculated values are outside the accepted range, meaning that both
will affect the analysis for body weight.
Table 1. Table with skewness and kurtosis
Paste table below:
Descriptive
s
Statistic Std. Error
Mean_heart_r Mean 132.65 3.541
ate_BPM
95% Confidence Lower 125.24
Interval for Mean Bound
Upper 140.06
Bound
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, EXSC 520
5% Trimmed 132.22
Mean
Median 133.50
Variance 250.766
Std. Deviation 15.836
Minimum 108
Maximum 165
Range 57
Interquartile 25
Range
Skewness .366 .512
Kurtosis -.519 .992
Body_weight_ Mean 85.845 2.7918
Kg
95% Confidence Lower 80.002
Interval for Mean Bound
Upper 91.688
Bound
5% Trimmed 84.728
Mean
Median 81.750
Variance 155.887
Std. Deviation 12.4855
Minimum 71.3
Maximum 120.5
Range 49.2
Interquartile 19.6
Range
Skewness 1.344 .512
Kurtosis 1.620 .992
Page 2 of 15
CASE STUDY: CORRELATION AND BIVARIATE REGRESSION TEMPLATE
I. Correlation
Research question: “Is mean heart rate during exercise correlate to body weight?”
Assumptions Testing
1. Data level of measurement – what was the level of measurement for the data used in this case
study (ratio, interval, etc.)?
The data level measurement for data used in this case is ratio. The four types of levels of
measurement are nominal, ordinal, interval, and ratio. All of these types of levels can either
be categorized, ranked, or infer equal intervals between data; however, ratio level is the only
level that can do all and have a true zero measurement. Both heart rate and body weight are
able to be categorized, ranked, have equal intervals between neighboring measurements and
have a true zero measurement, leaving ratio level being used for the case study
2. Would the amount of skewness and kurtosis in these variables affect the analysis? How do
you know? Give numerical values to support your conclusion.
For the amount of skewness or kurtosis to affect the analysis, the number must be below
-1.96 or above 1.96. Any value that comes between these two numbers is indicative of the
lack of skewness or kurtosis. The HR skewness had a calculated value of 0.7148, for HR
kurtosis, the calculated value is -0.5232. Both of these values fall in acceptable range, so
there is neither skewness or kurtosis for the heart rate. For BW skewness, the calculated
value was 2.625, for BW kurtosis, the calculated value is 1.6331. For body weight, both
skewness and kurtosis calculated values are outside the accepted range, meaning that both
will affect the analysis for body weight.
Table 1. Table with skewness and kurtosis
Paste table below:
Descriptive
s
Statistic Std. Error
Mean_heart_r Mean 132.65 3.541
ate_BPM
95% Confidence Lower 125.24
Interval for Mean Bound
Upper 140.06
Bound
Page 1 of 15
, EXSC 520
5% Trimmed 132.22
Mean
Median 133.50
Variance 250.766
Std. Deviation 15.836
Minimum 108
Maximum 165
Range 57
Interquartile 25
Range
Skewness .366 .512
Kurtosis -.519 .992
Body_weight_ Mean 85.845 2.7918
Kg
95% Confidence Lower 80.002
Interval for Mean Bound
Upper 91.688
Bound
5% Trimmed 84.728
Mean
Median 81.750
Variance 155.887
Std. Deviation 12.4855
Minimum 71.3
Maximum 120.5
Range 49.2
Interquartile 19.6
Range
Skewness 1.344 .512
Kurtosis 1.620 .992
Page 2 of 15
