sampling variability from a true, diurnal variation by an appropriate analysis (Received 14 April 1944)
|
|
- Ferdinand Simmons
- 5 years ago
- Views:
Transcription
1 1 J. Physiol. (I945) 104,1 I-5 J / 6I2. III. II DIURNAL AND SAMPLING VARIATIONS IN THE DETERMINATION OF HAEMOGLOBIN By R. H. MOLE, From the Pathological Laboratory, Radcliffe Infirmary, Oxford (Received 14 April 1944) When repeated determinations of haemoglobin are made on an individual animal or man, variations of as much as 20-30% may be found during the course of the day. Since such variations undoubtedly lie outside the range to be expected from the error of replicate determinations, they are assumed to be diurnal in character (Dreyer, Bazett & Pierce, 1920; Rabinowitch, 1924). A diurnal variation, however, would be expected to be regular and recurrent, yet the recorded results show haphazard and irregular alterations. These might be the' result of variability in repeated sampling of an individual's blood, independent of any diurnal variation and due to technical factors in taking the blood and to physiological alterations in the composition of the blood which are not necessarily diurnal. It is possible to distinguish this sampling variability from a true, diurnal variation by an appropriate analysis of the results of repeated,haemoglobin determinations. The method is the analysis of variance as developed by Fisher (1941, 1942), and this paper illustrates the value of the method when applied to the results obtained by McCarthy & Van Slyke (1939) and by others. If haemoglobin determinations are made at a nu'mber of different times of day and on a number of different individuals, the variability of the results will be due in part to differences between individuals, in part to differences in time of day when the blood samples are taken, and in part to the remaining causes of variation which make up the natural variability or uncontrolled error of the observations. The relative magnitudes of the mathematical expressions for the three parts into which the variability may be analysed make it possible to decide whether there are real diurnal differences. The details of the arithmetical work will not be described here as they are fully treated by" Fisher. In this paper the conventional probability level P= 1/20 or 0*05 has been taken as the border line between significant and non-significant differences (Fisher). PH. CIV..L 1
2 2 R. H. MOLE The most carefully carried out observations on diurnal variations in haemoglobin seem to be those by McCarthy & Van Slyke (1939), who used the carbon-monoxide capacity method of Van Slyke & Hiller (1928). This is probably the most accurate method of haemoglobin estimation there is. Earlier work was exhaustively reviewed by Smith (1931), but the results were obtained by less precise methods and are less well adapted for statistical analysis. TABLE 1. McCarthy & Van Slyke's results on twelve normal subjects in ml. of carbon monoxide capacity per 100 ml. of blood 9a.m. 11 a.m. 2p.m. 5p.m. 8p.m. 11 p.m. 19*97 19* Difference between 9 a.m. and 11 p.m. means =0-84±0-18 (see Table 2). Difference between 9 a.m. and 5 p.m. means=0-42. THE RESULTS OF MCCARTHY AND VAN SLYKE Full details of the observations are given in the original paper. The highest and lowest measurements on any one individual occurred at almost any time of day and differed on the average by 1-3 vol. CO, or 7% haemoglobin. Throughout this paper 100% haemoglobin has been assumed to equal 18'5 vol. of gas-combining capacity, as on Haldane's scale. The complete table of results has had to be split into two for statistical analysis, since five individuals were examined on 2 days each, and thirteen on 1 day only. Of these last, one 11 p.m. result is missing, so th4t the complete results on the remaining twelve will be first considered. The average figures for each of the sampling times are given in Table 1 and show a steady, if small, decline through the day. The analysis of variance is set out in Table 2 and the diurnal variation in blood carbon-monoxide capacity between 9 a.m. and 11 p.m. is found to be highly significant when compared with the uncontrolled error of the observations. TABLE 2. Analysis of variance of results on twelve subjects by McCarthy & Van Slyke Variance 9 a.m.-ll p.m. freedom Variance ratio Probability (P) Individual differences Diurnal differences Less than 0001 Uncontrolled error Standard deviation of repeated observations =V/ =0-46 vol. CO. Standard error of difference between two means each derived from twelve observations 2x vol. CO. It is also worth while to examine the smaller changes between 9 a.m. and 5 p.m., since these are the limits of the ordinary working day in laboratory and hospital. An exactly similar variance analysis (not given here) yields a value of P greater than 0 05 so that the diurnal variation over this shorter
3 DETERMINATION OF HAEMOGLOBIN 3 period is not statistically significant: nor does it become significant with the increase in the number of observations which results from including in the analysis the measurements of the five subjects on the first of the 2 days on which they were examined. It is unfortunately not possible to include the second-day results of these five subjects, since there is a marked difference (P less than 0.05) between the uncontrolled error variances of the five first-day and five second-day sets of results due to the much smaller uncontrolled error of the latter (Table 3). This means that the first- and second-day sets TABLE 3. Analysis of variance of results on five subjects by McCarthy & Van Slyke Second day First day* A Dgeso 9 a.m.-5 p.m. freedom Variance freedom Variance Individual differences Diurnal differences Uncontrolled error * The analysis is complicated by the loss of two measurements from the first-day series. The missing values have been estimated by minimizing the sum of squares for error as Fisher (1942) has suggested. This allows the utilization of the other observations on the individuals concerned, but the analysis is, of course, not as precise as if the missing value had actually been observed. The actual estimates here are and The difference in uncontrolled error variance between the first- and second-day series is not due to the use of estimated values. are not comparable and should not therefore be grouped as if they were. Nevertheless, this reduction in error is important from the experimental point of view, for the smaller the uncontrolled error the smaller the diurnal difference which is significant. Without the method of variance analysis this reduction in variability in the second 5-day set of results went undetected, so that the conditions under which the sampling variability of haemoglobin measurement was brought so low, although of great interest, were not recorded. DISCUSSION The method of variance analysis has provided an exact measure of the random variability of the results and of the probability of the averaged diurnal variations of all the subjects having occurred as a consequence of this random variability. In the last resort the significance of any particular value of P is always a matter of opinion, but its actual value is a property of the data and is fixed by them. However strict the criterion of significance, the analysis shows that there is a real diurnal variation, even if its size is much smaller than has been supposed. Diurnal variation, defined as a regular change in haemoglobin through the day, is found from McCarthy & Van Slyke's results to be a steady decrease amounting to about 4 % between 9 a.m. and 11 p.m. This is the average result obtained by eliminating differences between individuals and variability due to technical and sampling factors and thus represents a physiological normal value. 1-2
4 4 R. H. MOLE In advanced heart failure Rabinowitch & Strean (1924) made the interesting observation that there was a much smaller variability than in normal people. It should be pointed out that it is possible that the time of day for maximum and minimum haemoglobin levels may be different for different individuals. The method of analysis used in this paper will obscure any such individual differences in diurnal variation which will, on the other hand, go to swell the uncontrolled error. It would be possible to detect such individual differences by an analysis of repeated serial estimations on several days for each individual. The duplicate series of McCarthy & Van Slyke have been shown to differ so considerably in the magnitude of the uncontrolled error that they should not be considered as a homogeneous group of data, but if they are so grouped and analysed for differences in diurnal variation between individuals no such individual differences are found. The data do not bear out the suggestion that each individual has a characteristic diurnal variation of his own, though a large enough series of repeated observations might show that this hypothesis was true. The uncontrolled error of McCarthy & Van Slyke's observations consists of technical errors in the performance of the estimations, sampling variability and any other unspecified factors which affect the results. The variability of repeated estimations of carbon monoxide capacity on the same sample of blood is very small (Van Slyke & ililler). 'It is therefore safe to assume that the uncontrolled error of 'McCarthy & Van Slyke's data is almost entirely due to sampling variability, with the reservation discussed in the last paragraph. The variation with repeated sampling will be due to local environmental and metabolic influences which affect the composition of the blood in the vein from which the blood is taken, and also to more general factors which alter the proportion of red cells to plasma in the circulating blood. None of these variations are necessarily diurnal although they may normally occur in a regular manner during the day in relation to such regularly recurring events as meals. Any such regularly occurring changes will have been included in the diurnal variation in the analysis and by definition. Lastly, it is perhaps worth pointing out that if the diurnal variation is disregarded and included in the random variability, the standard deviation of repeated estimations is 054 vol. of carbon monoxide. On the normally accepted basis of twice the standard error, this means that there must be a difference of nearly 8 % between two haemoglobin estimations on one individual before this difference can be attributed with safety to anything but experimental error. In most experimental and clinical work where haemoglobin measurements are used to assess an experimental or therapeutic procedure, there will be at least as big an experimental ertor as this, against which the changes in haemoglobin' must be interpreted. The magnitude of
5 DETERMINATION OF HAEMOGLOBIN 5 sampling and diurnal variations sets a limit, too, beyond which it becomes no longer useful to increase the accuracy of haemoglobinometer readings. The limit is reached when the standard deviation of repeated measurements is about 1% on Haldane's scale. SUMMARY 1. Evidence for diurnal variations in haemoglobin has been examined by the method of variance analysis. 2. In the best series of observations there was a significant fall in haemoglobin between 9 a.m. and 11 p.m. of 0-8 vol. of carbon monoxide capacity, or about 4 %. 3. There was no significant diurnal change during the working day from 9 a.m. to 5 p.m. 4. The variation in haemoglobin content with repeated-sampling of venous blood has a standard deviation of 0 54 vol. of carbon monoxide, or 0-46 vol. after diurnal variation has been allowed for. REFERENCES Dreyer, G., Bazett, H. C. & Pierce, H. F. (1920). Lancet, 2, 588. Fisher, R. A. (1941). Stati8tical MethoS for Re8earch Workers. Edinburgh. Fisher, R. A. (1942). The Design of Experiment&. Edinburgh. McCarthy, E. F. & Van Slyke, D. D. (1939). J. biol. Chem. 128, 567. Rabinowitch, L M. (1924). J. Lab. din. Med. 9, 120. Rabinowitch, I. M. & Strean, G. (1924). Arch. intern. Med. 34, 124. Smith, C. (1931). Arch. inten. Med. 47, 206. Van Slyke, D. D. & Hiller, A. (1928). J. bil. Chem. 78, 807.
health and disease, and between one subject and another, have frequently been
76 J. Physiol. (949) IIO, 76-82 6I2.24 VARIABILITY OF THE VITAL CAPACITY OF THE NORMAL HUMAN SUBJECT BY J. N. MILLS Fellow of Jesus College, Cambridge From the Department of Physiology, University of Cambridge
More informationIN the course of making hemoglobin studies on large numbers
P R E L IM IN A R Y O B S E R V A T IO N S O N D IU R N A L A N D O T H E R V A R IA T IO N S IN H E M O G L O B IN L E V E L S 1 W alter W ilkins, M.D., Ph.D., and Ruth Blak ely, B.S. IN the course of
More informationM6ller, McIntosh and Van Slyke (5) has been employed. The cases. changes in functional activity. Indications suggesting that such changes
STUDIES OF UREA EXCRETION. VIII. THE EFFECTS ON THE UREA CLEARANCE OF CHANGES IN PROTEIN AND SALT CONTENTS OF THE DIET BY CUTHBERT L. COPE I (From the Hospital of the Rockefeller Institute for Medical
More informationIntroduction On Assessing Agreement With Continuous Measurement
Introduction On Assessing Agreement With Continuous Measurement Huiman X. Barnhart, Michael Haber, Lawrence I. Lin 1 Introduction In social, behavioral, physical, biological and medical sciences, reliable
More informationChapter 5: Field experimental designs in agriculture
Chapter 5: Field experimental designs in agriculture Jose Crossa Biometrics and Statistics Unit Crop Research Informatics Lab (CRIL) CIMMYT. Int. Apdo. Postal 6-641, 06600 Mexico, DF, Mexico Introduction
More informationGeorgina Salas. Topics EDCI Intro to Research Dr. A.J. Herrera
Homework assignment topics 51-63 Georgina Salas Topics 51-63 EDCI Intro to Research 6300.62 Dr. A.J. Herrera Topic 51 1. Which average is usually reported when the standard deviation is reported? The mean
More informationReview Statistics review 2: Samples and populations Elise Whitley* and Jonathan Ball
Available online http://ccforum.com/content/6/2/143 Review Statistics review 2: Samples and populations Elise Whitley* and Jonathan Ball *Lecturer in Medical Statistics, University of Bristol, UK Lecturer
More informationEstimation. Preliminary: the Normal distribution
Estimation Preliminary: the Normal distribution Many statistical methods are only valid if we can assume that our data follow a distribution of a particular type, called the Normal distribution. Many naturally
More informationMBA 605 Business Analytics Don Conant, PhD. GETTING TO THE STANDARD NORMAL DISTRIBUTION
MBA 605 Business Analytics Don Conant, PhD. GETTING TO THE STANDARD NORMAL DISTRIBUTION Variables In the social sciences data are the observed and/or measured characteristics of individuals and groups
More informationInferential Statistics
Inferential Statistics and t - tests ScWk 242 Session 9 Slides Inferential Statistics Ø Inferential statistics are used to test hypotheses about the relationship between the independent and the dependent
More informationStatistical analysis DIANA SAPLACAN 2017 * SLIDES ADAPTED BASED ON LECTURE NOTES BY ALMA LEORA CULEN
Statistical analysis DIANA SAPLACAN 2017 * SLIDES ADAPTED BASED ON LECTURE NOTES BY ALMA LEORA CULEN Vs. 2 Background 3 There are different types of research methods to study behaviour: Descriptive: observations,
More informationC-1: Variables which are measured on a continuous scale are described in terms of three key characteristics central tendency, variability, and shape.
MODULE 02: DESCRIBING DT SECTION C: KEY POINTS C-1: Variables which are measured on a continuous scale are described in terms of three key characteristics central tendency, variability, and shape. C-2:
More informationName Psychophysical Methods Laboratory
Name Psychophysical Methods Laboratory 1. Classical Methods of Psychophysics These exercises make use of a HyperCard stack developed by Hiroshi Ono. Open the PS 325 folder and then the Precision and Accuracy
More informationStatistics for Psychology
Statistics for Psychology SIXTH EDITION CHAPTER 3 Some Key Ingredients for Inferential Statistics Some Key Ingredients for Inferential Statistics Psychologists conduct research to test a theoretical principle
More informationChapter 4 DESIGN OF EXPERIMENTS
Chapter 4 DESIGN OF EXPERIMENTS 4.1 STRATEGY OF EXPERIMENTATION Experimentation is an integral part of any human investigation, be it engineering, agriculture, medicine or industry. An experiment can be
More informationThe Lens Model and Linear Models of Judgment
John Miyamoto Email: jmiyamot@uw.edu October 3, 2017 File = D:\P466\hnd02-1.p466.a17.docm 1 http://faculty.washington.edu/jmiyamot/p466/p466-set.htm Psych 466: Judgment and Decision Making Autumn 2017
More informationResearch Methods 1 Handouts, Graham Hole,COGS - version 1.0, September 2000: Page 1:
Research Methods 1 Handouts, Graham Hole,COGS - version 10, September 000: Page 1: T-TESTS: When to use a t-test: The simplest experimental design is to have two conditions: an "experimental" condition
More informationSOME PRINCIPLES OF FIELD EXPERlMENTS WITH SHEEP By P. G. SCHINCICEL *, and G. R. MOULE *
SOME PRINCIPLES OF FIELD EXPERlMENTS WITH SHEEP By P. G. SCHINCICEL *, and G. R. MOULE * Summary The principles of scientific method, with particular reference to the role of hypotheses and experiments
More information11-3. Learning Objectives
11-1 Measurement Learning Objectives 11-3 Understand... The distinction between measuring objects, properties, and indicants of properties. The similarities and differences between the four scale types
More information2 Critical thinking guidelines
What makes psychological research scientific? Precision How psychologists do research? Skepticism Reliance on empirical evidence Willingness to make risky predictions Openness Precision Begin with a Theory
More informationand accuracy D. Demilly (1) B. de Goyon (2) SNES GNIS-SOC (1) (2) GNIS - GEVES
Germination interlaboratory test variability and accuracy D. Demilly (1) B. de Goyon (2) (1) SNES (2) GNIS-SOC Statistical analysis use in France for germination ring tests or referee tests Statistical
More informationStatistics for Psychology
Statistics for Psychology SIXTH EDITION CHAPTER 12 Prediction Prediction a major practical application of statistical methods: making predictions make informed (and precise) guesses about such things as
More informationUse the above variables and any you might need to construct to specify the MODEL A/C comparisons you would use to ask the following questions.
Fall, 2002 Grad Stats Final Exam There are four questions on this exam, A through D, and each question has multiple sub-questions. Unless otherwise indicated, each sub-question is worth 3 points. Question
More informationbecause it enabled one to determine the reaction of the heart to slight by the use of acetylene (1) in the method previously described (2).
VARIATIONS IN THE CARDIAC OUTPUT OF MAN V. THE CARDIAC OUTPUT OF MAN DURING THE MALAISE AND PYREXiA FOLLOWING THE INJECTION OF TYPHOID VACCINE By ARTHUR GROLLMAN (From the Physiological Laboratory, School
More informationAnswer to Anonymous Referee #1: Summary comments
Answer to Anonymous Referee #1: with respect to the Reviewer s comments, both in the first review and in the answer to our answer, we believe that most of the criticisms raised by the Reviewer lie in the
More informationELEMENTS OF PSYCHOPHYSICS Sections VII and XVI. Gustav Theodor Fechner (1860/1912)
ELEMENTS OF PSYCHOPHYSICS Sections VII and XVI Gustav Theodor Fechner (1860/1912) Translated by Herbert Sidney Langfeld (1912) [Classics Editor's note: This translation of these passages from Fechner's
More informationEmpirical Tools of Public Finance. 131 Undergraduate Public Economics Emmanuel Saez UC Berkeley
Empirical Tools of Public Finance 131 Undergraduate Public Economics Emmanuel Saez UC Berkeley 1 DEFINITIONS Empirical public finance: The use of data and statistical methods to measure the impact of government
More information11/18/2013. Correlational Research. Correlational Designs. Why Use a Correlational Design? CORRELATIONAL RESEARCH STUDIES
Correlational Research Correlational Designs Correlational research is used to describe the relationship between two or more naturally occurring variables. Is age related to political conservativism? Are
More informationBreeding for Increased Protein Content in Milk
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Faculty Papers and Publications in Animal Science Animal Science Department January 1978 Breeding for Increased Protein
More informationThe Future of Exercise
The Future of Exercise (1997 and Beyond) ArthurJonesExercise.com 9 Requirements for Proper Exercise (con t) The relatively poor strength increases that were produced in the unworked range of movement during
More informationReliability and Validity
Reliability and Today s Objectives Understand the difference between reliability and validity Understand how to develop valid indicators of a concept Reliability and Reliability How accurate or consistent
More informationFREEZING POINTS OF ANTI-COAGULANT SALT SOLUTIONS
Published Online: 20 March, 1935 Supp Info: http://doi.org/10.1085/jgp.18.4.485 Downloaded from jgp.rupress.org on October 21, 2018 FREEZING POINTS OF ANTI-COAGULANT SALT SOLUTIONS B~ DAVID I. HITCI~OCK
More informationII. THE EFFECT OF THE INGESTION OF GLYCINE ON THE EXCRETION OF ENDOGENOUS URIC ACID.
PURINE METABOLISM. II. THE EFFECT OF THE INGESTION OF GLYCINE ON THE EXCRETION OF ENDOGENOUS URIC ACID. BY A. A. CHRISTMAN AND E. C. MOSIER. (From the Laboratory of Physiological Chemistry, Medical School,
More informationChapter 2--Norms and Basic Statistics for Testing
Chapter 2--Norms and Basic Statistics for Testing Student: 1. Statistical procedures that summarize and describe a series of observations are called A. inferential statistics. B. descriptive statistics.
More informationTHE EFFECT OF MENTAL STRESS ON THE EOSINOPHIL. Samter, 1951]. According to Rud [1947] there is a large fall between early morning
THE EFFECT OF MENTAL STRESS ON THE EOSINOPHIL LEUCOCYTE COUNT IN MAN.' By A. C. KERR.2 From the Institute of Physiology, University of Glasgow. (Received for publication 2nd Augu8t 1955) A FALL in the
More informationMeasurement and Descriptive Statistics. Katie Rommel-Esham Education 604
Measurement and Descriptive Statistics Katie Rommel-Esham Education 604 Frequency Distributions Frequency table # grad courses taken f 3 or fewer 5 4-6 3 7-9 2 10 or more 4 Pictorial Representations Frequency
More informationAnalysis of Variance (ANOVA) Program Transcript
Analysis of Variance (ANOVA) Program Transcript DR. JENNIFER ANN MORROW: Welcome to Analysis of Variance. My name is Dr. Jennifer Ann Morrow. In today's demonstration, I'll review with you the definition
More informationDISTRIBUTION OF HAEMOGLOBIN LEVEL, PACKED CELL VOLUME, AND MEAN CORPUSCULAR HAEMOGLOBIN
Brit. J. prev. soc. Med. (1964), 18, 81-87 DISTRIBUTION OF HAEMOGLOBIN LEVEL, PACKED CELL VOLUME, AND MEAN CORPUSCULAR HAEMOGLOBIN CONCENTRATION IN WOMEN IN THE COMMUNITY The definition of anaemia in most
More informationOne-Way ANOVAs t-test two statistically significant Type I error alpha null hypothesis dependant variable Independent variable three levels;
1 One-Way ANOVAs We have already discussed the t-test. The t-test is used for comparing the means of two groups to determine if there is a statistically significant difference between them. The t-test
More informationStandard Errors of Correlations Adjusted for Incidental Selection
Standard Errors of Correlations Adjusted for Incidental Selection Nancy L. Allen Educational Testing Service Stephen B. Dunbar University of Iowa The standard error of correlations that have been adjusted
More informationTesting the capacity of biological buffer systems to resist changes in ph By P. H. Meter
Testing the capacity of biological buffer systems to resist changes in ph By P. H. Meter Personal Engagement and Exploration Research Question: How do plant and animal tissues respond to changes in ph?
More information25. Two-way ANOVA. 25. Two-way ANOVA 371
25. Two-way ANOVA The Analysis of Variance seeks to identify sources of variability in data with when the data is partitioned into differentiated groups. In the prior section, we considered two sources
More informationMeasurement. 500 Research Methods Mike Kroelinger
Measurement 500 Research Methods Mike Kroelinger Levels of Measurement Nominal Lowest level -- used to classify variables into two or more categories. Cases placed in the same category must be equivalent.
More informationCANCER FACTS & FIGURES For African Americans
CANCER FACTS & FIGURES For African Americans Pennsylvania, 2006 Pennsylvania Cancer Registry Bureau of Health Statistics and Research Contents Data Hightlights...1 Pennsylvania and U.S. Comparison...5
More informationSmith, Miller and Grab er(4) state that the maintenance of an efficient
THE SIGNIFICANCE OF THE DIASTOLIC AND SYSTOLIC BLOOD-PRESSURES FOR THE MAINTENANCE OF THE CORONARY CIRCULATION. BY G. V. ANREP AND B. KING. (From the Physiological Laboratory, Cambridge.) IT is generally
More informationMortality in relation to alcohol consumption: a prospective study among male British doctors
IJE vol.34 no.1 International Epidemiological Association 2005; all rights reserved. International Journal of Epidemiology 2005;34:199 204 Advance Access publication 12 January 2005 doi:10.1093/ije/dyh369
More information1. Below is the output of a 2 (gender) x 3(music type) completely between subjects factorial ANOVA on stress ratings
SPSS 3 Practice Interpretation questions A researcher is interested in the effects of music on stress levels, and how stress levels might be related to anxiety and life satisfaction. 1. Below is the output
More information(Received 22 January 1941)
510 J. Physiol. (94I) 99, 50-514 6I2.0I4.44:612.III EFFECT OF LIGHT ON RED BLOOD CELLS. THE LIGHT SENSITIVITY OF BLOOD FROM DIFFERENT VERTEBRATE SPECIES BY W. MEYERSTEIN (From the Department of Physiology,
More informationPSYCHOLOGY 300B (A01) One-sample t test. n = d = ρ 1 ρ 0 δ = d (n 1) d
PSYCHOLOGY 300B (A01) Assignment 3 January 4, 019 σ M = σ N z = M µ σ M d = M 1 M s p d = µ 1 µ 0 σ M = µ +σ M (z) Independent-samples t test One-sample t test n = δ δ = d n d d = µ 1 µ σ δ = d n n = δ
More informationGENERALIZABILITY AND RELIABILITY: APPROACHES FOR THROUGH-COURSE ASSESSMENTS
GENERALIZABILITY AND RELIABILITY: APPROACHES FOR THROUGH-COURSE ASSESSMENTS Michael J. Kolen The University of Iowa March 2011 Commissioned by the Center for K 12 Assessment & Performance Management at
More informationHS Exam 1 -- March 9, 2006
Please write your name on the back. Don t forget! Part A: Short answer, multiple choice, and true or false questions. No use of calculators, notes, lab workbooks, cell phones, neighbors, brain implants,
More informationSheila Barron Statistics Outreach Center 2/8/2011
Sheila Barron Statistics Outreach Center 2/8/2011 What is Power? When conducting a research study using a statistical hypothesis test, power is the probability of getting statistical significance when
More informationREGRESSION MODELLING IN PREDICTING MILK PRODUCTION DEPENDING ON DAIRY BOVINE LIVESTOCK
REGRESSION MODELLING IN PREDICTING MILK PRODUCTION DEPENDING ON DAIRY BOVINE LIVESTOCK Agatha POPESCU University of Agricultural Sciences and Veterinary Medicine Bucharest, 59 Marasti, District 1, 11464,
More informationThe Stroop Effect The Effect of Interfering Colour Stimuli Upon Reading Names of Colours Serially ABSTRACT
The Stroop Effect The Effect of Interfering Colour Stimuli Upon Reading Names of Colours Serially ABSTRACT This experiment, a partial duplication of the work of Stroop (l935) l, aimed to demonstrate the
More informationInterpretation of Data and Statistical Fallacies
ISSN: 2349-7637 (Online) RESEARCH HUB International Multidisciplinary Research Journal Research Paper Available online at: www.rhimrj.com Interpretation of Data and Statistical Fallacies Prof. Usha Jogi
More informationExploration and Exploitation in Reinforcement Learning
Exploration and Exploitation in Reinforcement Learning Melanie Coggan Research supervised by Prof. Doina Precup CRA-W DMP Project at McGill University (2004) 1/18 Introduction A common problem in reinforcement
More informationApplied Statistical Analysis EDUC 6050 Week 4
Applied Statistical Analysis EDUC 6050 Week 4 Finding clarity using data Today 1. Hypothesis Testing with Z Scores (continued) 2. Chapters 6 and 7 in Book 2 Review! = $ & '! = $ & ' * ) 1. Which formula
More informationThe degree to which a measure is free from error. (See page 65) Accuracy
Accuracy The degree to which a measure is free from error. (See page 65) Case studies A descriptive research method that involves the intensive examination of unusual people or organizations. (See page
More informationEditorial Note: this manuscript has been previously reviewed at another journal that is not operating a transparent peer review scheme.
Editorial Note: this manuscript has been previously reviewed at another journal that is not operating a transparent peer review scheme. This document only contains reviewer comments and rebuttal letters
More informationChi Square Goodness of Fit
index Page 1 of 24 Chi Square Goodness of Fit This is the text of the in-class lecture which accompanied the Authorware visual grap on this topic. You may print this text out and use it as a textbook.
More informationSMOKING HABITS RELATED TO INJURY AND
Brit. J. prev. soc. Med. (196), 14, 57 SMOKING HABITS RELATED TO INJURY AND ABSENTEEISM IN INDUSTRY BY C. R. LOWE From the Department of Social Medicine, University of Birmingham In February, 1957, a mass
More informationPsychology Research Process
Psychology Research Process Logical Processes Induction Observation/Association/Using Correlation Trying to assess, through observation of a large group/sample, what is associated with what? Examples:
More informationInterpreting the Item Analysis Score Report Statistical Information
Interpreting the Item Analysis Score Report Statistical Information This guide will provide information that will help you interpret the statistical information relating to the Item Analysis Report generated
More informationMedicine, Cambridge, England, and Wuppertal, B.A.O.R.
182 J. Physiol. (I948) I07, i82-i86 6I2.46I.62 PHOSPHATE CLEARANCES IN INFANTS AND ADULTS BY R. F. A. DEAN AND R. A. McCANCE From the Medical Research Council, Department. of Experimental Medicine, Cambridge,
More informationAssignment #6. Chapter 10: 14, 15 Chapter 11: 14, 18. Due tomorrow Nov. 6 th by 2pm in your TA s homework box
Assignment #6 Chapter 10: 14, 15 Chapter 11: 14, 18 Due tomorrow Nov. 6 th by 2pm in your TA s homework box Assignment #7 Chapter 12: 18, 24 Chapter 13: 28 Due next Friday Nov. 13 th by 2pm in your TA
More informationAn introduction to power and sample size estimation
453 STATISTICS An introduction to power and sample size estimation S R Jones, S Carley, M Harrison... Emerg Med J 2003;20:453 458 The importance of power and sample size estimation for study design and
More informationMARK SCHEME for the May/June 2011 question paper for the guidance of teachers 9699 SOCIOLOGY
UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS GCE Advanced Subsidiary Level and GCE Advanced Level MARK SCHEME for the May/June 2011 question paper for the guidance of teachers 9699 SOCIOLOGY 9699/23
More informationCHAPTER 3 DATA ANALYSIS: DESCRIBING DATA
Data Analysis: Describing Data CHAPTER 3 DATA ANALYSIS: DESCRIBING DATA In the analysis process, the researcher tries to evaluate the data collected both from written documents and from other sources such
More informationTo open a CMA file > Download and Save file Start CMA Open file from within CMA
Example name Effect size Analysis type Level Tamiflu Symptom relief Mean difference (Hours to relief) Basic Basic Reference Cochrane Figure 4 Synopsis We have a series of studies that evaluated the effect
More informationData, frequencies, and distributions. Martin Bland. Types of data. Types of data. Clinical Biostatistics
Clinical Biostatistics Data, frequencies, and distributions Martin Bland Professor of Health Statistics University of York http://martinbland.co.uk/ Types of data Qualitative data arise when individuals
More informationInvestigating the robustness of the nonparametric Levene test with more than two groups
Psicológica (2014), 35, 361-383. Investigating the robustness of the nonparametric Levene test with more than two groups David W. Nordstokke * and S. Mitchell Colp University of Calgary, Canada Testing
More informationMath 261 Exam I Spring Name:
Math 261 Exam I Spring 2008 Name: Instructions: Write your answers clearly on the exam paper. Show work to receive partial credit. Use the back of the page if you need more space but please note that you
More informationUsing the ISO characterized reference print conditions to test an hypothesis about common color appearance
Using the ISO 15339 characterized reference print conditions to test an hypothesis about common color appearance John Seymour 1, Sept 23, 2016 Abstract If I view an ad for my favorite cola in a newspaper
More informationExamining differences between two sets of scores
6 Examining differences between two sets of scores In this chapter you will learn about tests which tell us if there is a statistically significant difference between two sets of scores. In so doing you
More informationdoi: /
doi: 10.1177/1049909113504982 Prospective clarification of the utility of the Palliative Prognostic Index for advanced cancer patients in the home care setting Introduction Making prognostic predictions
More informationProtoporphyrin in Lead-Exposed
Environmental Health Perspectives Vol. 25, pp. 97-12, 1978 Hemoglobin, Serum Iron, and Zinc Protoporphyrin in Lead-Exposed Workers by Ruth Lilis,* J. Eisinger,t W. Blumberg,t A. Fischbein,* and 1. J. Selikoff*
More informationestimates were made of the normal rate of increase in plasma urea over periods in skin and in plasma, hypertonic sodium chloride solution was
482 J. Physiol. (I95I) II5, 482-487 THE STTE OF BODY WTER IN THE CT BY M. GRCE EGGLETON From the Department of Physiology, University College, London (Received 5 July 1951) In the course of an investigation
More informationSTATISTICS AND RESEARCH DESIGN
Statistics 1 STATISTICS AND RESEARCH DESIGN These are subjects that are frequently confused. Both subjects often evoke student anxiety and avoidance. To further complicate matters, both areas appear have
More informationBig Idea 1 The Practice of Science. Big Idea 2 The Characteristics of Scientific Knowledge
Big Idea 1 The Practice of Science Big Idea 2 The Characteristics of Scientific Knowledge SC.5.N.1.2 Explain the difference between an experiment and other types of scientific investigation SC.5.N.1.5
More informationDO NOT OPEN THIS BOOKLET UNTIL YOU ARE TOLD TO DO SO
NATS 1500 Mid-term test A1 Page 1 of 8 Name (PRINT) Student Number Signature Instructions: York University DIVISION OF NATURAL SCIENCE NATS 1500 3.0 Statistics and Reasoning in Modern Society Mid-Term
More informationSpatially Diffuse Inhibition Affects Multiple Locations: A Reply to Tipper, Weaver, and Watson (1996)
Journal of Experimental Psychology: Human Perception and Performance 1996, Vol. 22, No. 5, 1294-1298 Copyright 1996 by the American Psychological Association, Inc. 0096-1523/%/$3.00 Spatially Diffuse Inhibition
More informationd =.20 which means females earn 2/10 a standard deviation more than males
Sampling Using Cohen s (1992) Two Tables (1) Effect Sizes, d and r d the mean difference between two groups divided by the standard deviation for the data Mean Cohen s d 1 Mean2 Pooled SD r Pearson correlation
More informationSICKNESS ABSENCE BEFORE THE FIRST CLINICAL
Brit. J. industr. Med., 1954, 11, 20. SICKNESS ABSENCE BEFORE THE FIRST CLINICAL EPISODE OF CORONARY HEART DISEASE BY J. A. HEADY, J. N. MORRIS, F. J. LLOYD, and P. A. B. RAFFLE From the Social Medicine
More informationChapter 2 Norms and Basic Statistics for Testing MULTIPLE CHOICE
Chapter 2 Norms and Basic Statistics for Testing MULTIPLE CHOICE 1. When you assert that it is improbable that the mean intelligence test score of a particular group is 100, you are using. a. descriptive
More informationInvestigating the Effect of Time on the Plasmolysis of Potatoes
Investigating the Effect of Time on the Plasmolysis of Potatoes Research Question What causes potatoes to go soft after being stored for a long time? Aim The aim of this experiment is to investigate how
More informationData and Statistics 101: Key Concepts in the Collection, Analysis, and Application of Child Welfare Data
TECHNICAL REPORT Data and Statistics 101: Key Concepts in the Collection, Analysis, and Application of Child Welfare Data CONTENTS Executive Summary...1 Introduction...2 Overview of Data Analysis Concepts...2
More informationErica J. Yoon Introduction
Replication of The fluency of social hierarchy: the ease with which hierarchical relationships are seen, remembered, learned, and liked Zitek & Tiedens (2012, Journal of Personality and Social Psychology)
More informationCompletely randomized designs, Factors, Factorials, and Blocking
Completely randomized designs, Factors, Factorials, and Blocking STAT:5201 Week 2: Lecture 1 1 / 35 Completely Randomized Design (CRD) Simplest design set-up Treatments are randomly assigned to EUs Easiest
More informationINADEQUACIES OF SIGNIFICANCE TESTS IN
INADEQUACIES OF SIGNIFICANCE TESTS IN EDUCATIONAL RESEARCH M. S. Lalithamma Masoomeh Khosravi Tests of statistical significance are a common tool of quantitative research. The goal of these tests is to
More informationA Genetic Analysis of Taste Deficiency in the American Negro
The Ohio State University Knowledge Bank kb.osu.edu Ohio Journal of Science (Ohio Academy of Science) Ohio Journal of Science: Volume 34, Issue 5 (September, 1934) 1934-09 A Genetic Analysis of Deficiency
More informationEXERCISE: HOW TO DO POWER CALCULATIONS IN OPTIMAL DESIGN SOFTWARE
...... EXERCISE: HOW TO DO POWER CALCULATIONS IN OPTIMAL DESIGN SOFTWARE TABLE OF CONTENTS 73TKey Vocabulary37T... 1 73TIntroduction37T... 73TUsing the Optimal Design Software37T... 73TEstimating Sample
More informationStandard Deviation and Standard Error Tutorial. This is significantly important. Get your AP Equations and Formulas sheet
Standard Deviation and Standard Error Tutorial This is significantly important. Get your AP Equations and Formulas sheet The Basics Let s start with a review of the basics of statistics. Mean: What most
More informationdisturbance. mellitus, are known to result in, or be associated with, a disturbance study has, recently, been made (1). In a comprehensive study,
BLOOD SUGAR TIME CURVES BY I. M. RABINOWITCH (From the Department of Metabolism, Montreal General Hospital, Montreal, Canada) (Received for publication May 2, 926) Blood sugar time curves, or what are
More informationWELS~~~~ THE mode of action of acetyl choline upon the isolated ventricular strip
THE ANTAGONISM OF ACETYL CHOLINE BY ATROPINE. BY A. J. CLARK. (From the Pharmacological Department, University College, London.) THE mode of action of acetyl choline upon the isolated ventricular strip
More informationSHORT AND LONG MEMORIES IN OCTOPUS AND THE INFLUENCE OF THE VERTICAL LOBE SYSTEM
J. Exp. Biol. (1970), 53. 385-393 385 With 4 text-figures fprinted in Great Britain SHORT AND LONG MEMORIES IN OCTOPUS AND THE INFLUENCE OF THE VERTICAL LOBE SYSTEM BY J. Z. YOUNG Department of Anatomy,
More informationblood contained within the minute vessels were Fifteen experiments were performed on six normal
DEMONSTRATION THAT THE CELL PLASMA RATIO OF BLOOD CONTAINED IN MINUTE VESSELS IS LOWER THAN THAT OF VENOUS BLOOD By RICHARD V. EBERT AND EUGENE A. STEAD, JR. (From the Medical Clinic of the Peter Bent
More informationCushny(4) has shown, however, that the amount of urea in the kidney. by some vital process, retain those diflusible substances which are of
THE FUNCTION OF THE TUBULES IN KIDNEY EXCRETION. BY E. B. MAYRS. (From the Department of Pharmacology, Edinburgh.) IT is becoming generally recognised that filtration through the glomeruli and some degree
More informationP02 for Hb = HbO2 at cell
OXYGEN DISSOCIATION CURVES IN SICKLE CELL ANEMIA AND IN SUBJECTS WITH THE SICKLE CELL TRAIT By MARGARET R. BECKLAKE, S. B. GRIFFITHS, M. McGREGOR, H. I. GOLDMAN, AND J. P. SCHREVE (From the Cardiopulmonary
More informationLessons in biostatistics
Lessons in biostatistics The test of independence Mary L. McHugh Department of Nursing, School of Health and Human Services, National University, Aero Court, San Diego, California, USA Corresponding author:
More informationPolitical Science 15, Winter 2014 Final Review
Political Science 15, Winter 2014 Final Review The major topics covered in class are listed below. You should also take a look at the readings listed on the class website. Studying Politics Scientifically
More information