1. Introduction to Study Skills & Research Methods (HL10040)
Measurement Errors
Introduction to Study Skills & Research Methods (HL10040)
Dr James Betts

2. Lecture Outline: Measurement Errors Continued Types of Errors
Assessment of Error
Introduction to Inferential Statistics
Chi-Squared tests
Assessment Details.

3. Measurement Errors Virtually all measurements have errors
Reliability and Measurement Error are not the same, rather Reliability infers an acceptable degree of Measurement Error.

4. SD

5. This total variance can then be ‘partitioned’

6. Systematic/Random Error
% Body-fat
Subject 1
Subject 2
Subject 3
Subject 4
Skin-Fold Callipers
Hydrostatic Weighing

7. Assessment of Error
Systematic Error

8. Assessment of Error
Random Error

9. 3 points of visual assessment:
Assessment of Error
Systematic & Random Error
3 points of visual assessment:
-Systematic Error:
-Random Error:
-Nature of error:

11. Dependent Variable
Independent
Variable
Total Variance
between trial 1
& trial 2
Systematic
Variance
Extraneous/
Confounding
(Error) Variables

12. Smallest Worthwhile Effect

13. Re-Run

14. Introduction to Inferential Statistics
Before our next lecture you will be conducting some inferential statistics in your lab classes
All you need to be aware of at this stage is that the ‘P-value’ represents the probability that total variance is not due to primary variance

15. Goodness of fit χ2 test
SPSS Output

16. Contingency χ2 test
SPSS Output

17. Selected Reading
I know error and variance can be confusing topics, try these:
Atkinson, G. and A. M. Nevill. Statistical methods for assessing measurement error (Reliability) in variables relevant to sports medicine. Sports Medicine. 26: , 1998.
Hopkins, W. G. et al. Design and analysis of research on sport performance enhancement. Med. Sci. Sport and Exerc. 31: , 1999.
Hopkins, W. G. et al. Reliability of power in physical performance tests. Sports Medicine. 31: , 2001.
Atkinson, G., ''What is this thing called measurement error?'' , in Kinanthropometry VIII: Proceedings of the 8th International Conference of the International Society for the Advancement of Kinanthropometry (ISAK) , Reilly, T. and Marfell-Jones, M. (Eds.), Taylor and Francis, London , 2003.

18. Coursework (60% overall grade)
Your coursework will require you to address 2 of the following research scenarios:
1) Effect of Plyometric Training on Vertical Jump
2) Effect of Ice Baths on Recovery of Strength
3) Effect of Diet on the Incidence of Muscle Injury
4) Effect of Footwear on Sprint Acceleration
5) Effect of PMR on Competitive Anxiety.

19. Coursework Outline For each of the 2 scenarios you will need to:
Perform a literature search in order to provide a comprehensive introduction to the research area
Identify the variables of interest and evaluate the research design which was adopted
Formulate and state appropriate hypotheses
Summarise descriptive statistics in an appropriate and well presented manner…

20. Coursework Outline Cont’d…
Select the most appropriate statistical test with justification for your decision
Transfer the output of your inferential statistics into your word document
Interpret your results and discuss the validity and reliability of the study
Draw a meaningful conclusion (state whether hypotheses are accepted or rejected).

21. Coursework Details (see unit outline)
2000 words maximum (i.e. 1000 for each)
Any supporting SPSS data/outputs to be appended
To be submitted on Tuesday 14th December
Assessment Weighting
Evaluation & Analysis (30 %)
Reading & Research (20 %)
Communication & Presentation (20 %)
Knowledge (30 %)

22. Web address also referenced on shared area
Coursework Details
All information relating to your coursework (including the relevant data files) are accessible via the unit web page:
Web address also referenced on shared area

23. Mid-Term Test (40% overall grade)
NEXT WEEK
This test will involve short answer questions covering all the information covered so far
Mostly knowledge recall but will require understanding and possibly some calculations
Duration = 50 min
So…

24. Mid-Term Test (40% overall grade)
Surnames: A-F
Arrive promptly at am for start of test at am
Exit in silence afterwards
Surnames: G-Z
Arrive promptly at am for start of test at am
Exit however you like!