Research & Summaries Question
Description
You are provided with a practice data sheet (see ‘week 9 data’ below). Measure and discuss test-retest reliability for waist measurements A and B (e.g., compute CV% and correlation in excel). SEE THE VIDEO EXAMPLE BELOW
Unformatted Attachment Preview
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
height
weight
fatper
FFM
waist
71.54
224.2
29.7
157.61
71.05
227.6
25.2
170.21
72.05
194.2
21
153.4
65.96
163.4
18.6
133
76.06
194.2
12.7
169.6
74.03
190.2
17.4
157.2
69.94
165.6
17.2
137.21
74.48
187
15.7
157.6
73.06
205
17.5
169.21
71.9
189
18
153.4
66.96
155.6
15.4
131.6
71.96
179
16.8
149.01
68.02
196.8
26.9
143.8
73.01
213.8
19.5
172.2
59.01
117.4
22.9
90.61
68.92
139.2
26.8
101.81
65
125.6
22
98.01
64.72
112
15
100
66.89
210
43
120.2
68.97
180
31.5
123.2
60.04
92.8
13.1
80.6
65.43
121.2
23.6
92.6
64.29
194
45
106
64.02
164.4
36
105.2
65.4
115
15.9
18.41
63.93
144.2
29.7
101.4
68.46
178
36
114
65.04
140.2
32.3
95.01
64.01
122.4
21
96.6
62.04
116.6
24.3
88.2
67.97
147.2
28.2
46.61
61.97
134.4
28.2
96.6
66.97
164.6
38
102.1
67.01
135.4
22.6
104.81
67.02
124.6
23.9
94.9
63.02
106.2
17.7
87.41
67.04
146.4
26
108.41
67.54
135.6
25.3
101.2
69.93
177.4
31.5
121.61
60.03
110.2
21.3
86.8
66.97
141
26.9
103
66.03
117.2
19.6
94.2
63.97
124
17.9
101.8
65.01
107
20.8
84.81
63.96
109.4
14.7
93.41
65
122
19.3
98.4
waist
40
38
35
31
34
35
33
32
34
32
30
34
39
33
27
29
27
26
37
35
26
29
39
36
30
31
37
28
27
27
32
28
29
27
27
27
31
27
29
26
28
25
26
25
25
26
BMI
40.3
37.8
33.8
32
34
32.8
30.5
32
34
33
30.8
32
38
33.3
27.8
29.8
26.3
26.5
38.3
34.5
25
28.3
38
35.5
27.5
36
35.3
28
27
27.8
31.8
28.3
30.3
26.3
27.7
24.8
29.8
27
28.8
25
29
25
25.8
23.8
24.3
26
PA
30.8
31.7
26.3
26.4
23.6
24.4
23.8
23.7
27
25.7
24.4
24.3
29.9
28.2
23.7
20.6
20.9
18.8
33
26.6
18.1
19.9
33
28.2
18.9
24.8
26.7
23.3
21
21.3
22.4
24.6
25.8
21.2
19.5
18.8
22.9
20.9
25.5
21.5
22.1
18.9
21.3
17.8
18.8
20.3
30
90
0
60
60
0
45
0
120
0
0
60
0
60
90
50
30
45
0
90
0
30
20
40
20
20
90
90
0
10
60
20
90
90
60
90
30
35
90
0
0
45
45
0
45
60
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
1
2
68.94
60
68.94
68.02
66
60.1
66
60
62
64
62
63
63
64.5
62
74
67
144
106
177.8
149.4
136
161.4
141.4
119.6
219.2
155.6
125.8
162.2
127
130.6
119.8
155.2
154.4
27.8
14.6
34
30
24.3
35.6
25.5
22.4
48.4
38.9
20.6
34.8
29.3
24.3
18.9
11.3
32.5
104.61
90.6
117.4
104.6
103.2
104.01
105.4
92.8
113.2
60.6
99.8
105.8
89.8
98.8
97.2
137.6
104.2
28
25
31
29
28.5
34
30.5
30.3
45
32
27
32.5
28.5
29.3
28.8
32
32
27.5
24.5
31
29
28
34.5
30.5
30
43.5
32.4
27.5
32.1
29.5
27.5
28.4
32.2
31.4
21.3
20.7
26.3
22.7
22
26.1
22.8
23.4
40.1
26.7
23
28.7
22.5
22.1
21.9
19.9
24.2
90
45
90
80
54
33
35
33
60
54
115
37
46
21
161
62
29
Week 5
Reliability
Video
Note that this video was presented for the Fall
2022 NTR500 course (ence the due dates for
assignment 9 are not correct. Assignment 9 is
due 2/11 at 11:59 pm.
Reliability =
the quality of measurement
the “consistency” or “repeatability” of your measures
True score theory
Every measurement is an additive composite of two components:
true ability (or the true level) of the measure
% random error of the measure
But all error is not random
-some errors are systematic
Random Error
Caused by any factors that randomly affect measurement of the variable
across the sample.
random error can be
considered noise
Systematic Error
Caused by any factors that randomly affect measurement of the variable
across the sample.
systematic error = bias
To Avoid Errors:
0ilot test and calibrate instruments
‘et feedback by pre-testing
4rain investigators thoroughly
$ouble-check data entry
5se statistical procedures to adjust for measurement
error
5se multiple measures of the same construct triangulate across the multiple measures to get a
more accurate sense of what’s going on
Test-Retest reliability
How consistent is the
measurement across time? Test
with CV(%) and correlation.
Inter-Rater reliability
If more than one researcher is
collecting data, are the measurements
being done the same? Test with
correlation and Cronbachà?.
Coefficient of variance
he calculation of Coefficient of Variation (CV) from duplicate
measurements made on a number of different subjects or
materials is used to determine the reproducibility of the
measurements
The coefficient of variation should typically only be used for data
measured on a ratio scale (e.g, blood values). Desired value is
Purchase answer to see full
attachment
Have a similar assignment? "Place an order for your assignment and have exceptional work written by our team of experts, guaranteeing you A results."