how to report partial eta squared apa

/C [0 1 0] In this way, the MANOVA essentially tests whether or not the independent grouping variable simultaneously explains a statistically significant amount of variance in the dependent variable. Pierce, C.A., Block, R. A., and Aguinis, H. (2004). /Pages 12 0 R An explanation of sphericity is provided in our Sphericity guide. 503 0 obj<>stream Cumming, G. (2012). 0000002889 00000 n /H /I /Border [0 0 0] Comparing the relative effect of the intervention on the two outcomes would be difficult on their original scales. >> Effect sizes that measure the scaled difference between means belong to the d family. cfVgeu6M!M~E /PrintState /ON Washington, DC: American Psychological Association. /A << Statology Study is the ultimate online statistics study guide that helps you study and practice all of the core concepts taught in any elementary statistics course and makes your life so much easier as a student. >> 33 0 obj Acrobat Distiller 8.1.0 (Windows) /Subtype /Link /Border [0 0 0] /Type /Annot endobj /Dest (cite.bib31) /CreationDate (D:20131119120056+05'30') Eta-squared ( 2) and partial eta-squared ( p2) are effect sizes that express the amount of variance accounted for by one or more independent variables. /Dest (cite.bib26) /C [0 1 1] The EFP and GHG emissions were significantly related to geographical locations (i.e., southern and northern areas), direct economic indicators (i.e., PCDI and food expenditure), and indirect economic indicators (i.e., urban and rural status, and East-Central-West areas) (all p<0.01). This means we can reject the null hypothesis and accept the alternative hypothesis. Although the number of studies is limited, based on the size Cohens d statistics calculated in this review, there is evidence to suggest that Reiki therapy may be effective for pain and anxiety. WebTo report influence or importance other coefficients are possible besides the partial Eta squared. /Rect [66.789 455.952 117.228 463.146] The value for Partial eta squared ranges from 0 to 1, where values closer to 1 indicate a higher proportion of variance that can be explained by a given variable in the model after accounting for variance explained by other variables in the model. The Center for Reiki Research also was examined for articles. Mixed effects models have become increasingly prominent in sensory and consumer science. WIN reduced SWD number in epoch 2 and 3, their mean duration increased in epochs 3 and 4. << /Type /Annot 38 0 obj These findings suggest that, besides economic indicators, more attention should be paid to the geographical locations and the related dietary cultures to reduce the environmental impacts not only in China but also in other countries with distinct regional differences. /Dest (cite.bib7) /Type /Annot /H /I The six-month exercise-training programme had a statistically significant effect on fitness levels, F(2, 10) = 12.53, p = .002. /Properties << No correlation was found between pain severity, pain duration, LRJT performance, and TPDTs. /H /I /Border [0 0 0] The overall 2 indicates that our model accounts for approximately 26.7% of the variablity in math scores though the 95% confidence interval includes the null value of zero (0.00%, 40.7%). In an ANOVA, we examine for statistical differences on one continuous dependent variable by an independent grouping variable. /Type /Annot /Dest (cite.bib13) /Border [0 0 0] It has subsequently been generalized to nonexperimental studies. All of which is to say, one should report parameter estimates along with statistical significance. >> In this paper we introduce an approach for automated mixed ANOVA/ANCOVA modeling together with the open source R package lmerTest developed by the authors that can perform automated complex mixed-effects modeling. >> xref The classical formulation of eta squared (K. Pearson, 1911; R. A. Fisher, endobj /S /URI SPSS: Can be performed using the analysis menu, selecting the GLM option, and then choosing the Multivariate option from the GLM option. /Subtype /Link /Fm0 70 0 R >> >> 7 0 obj << This means This tendency was more prevalent when reviews were presented in disaggregated format. /C [0 1 0] To take the hypothetical example in Table 1, the only situation in which 2 and partial 2 could equal 1 is one in which all the boys obtain one score and all the girls obtain some other score. Accordingly, having learners practice with the expectation of teaching and techniques that minimize the accrual of declarative knowledge is recommended. Using multivariate statistics (6th ed.). Educational and Psychological Measurement 65: 5169. We also highlight issues with the interpretation of effects coding, and put forward a more well-defined version of effects coding. /S /URI Similarly, treatment status accounted for almost none of the variability in reading scores while it accounted for roughly 17% of the variability in math scores. For example, if we know the numerator and denominator degrees of freedom along with the F statistic, we can calculate 2 and 2 using the following command: Stata has dialog boxes that can assist you in calculating effect sizes. /Filter /FlateDecode 42 0 obj When comparing more than two groups of people, we commonly use eta squared or partial eta squared. stream /Length 1074 This data comes from the independent t-test chapter. /Type /Metadata >> Webpetasq Partial Eta Squared Description Partial Eta Squared Usage petasq(x, effect) Arguments x A call to aov, ez::ezANOVAor afex::aov_ezor afex::aov_caror afex::aov_4 effect Character string indicating the name of the effect for which the partial eta squared should be returned. 2013-12-06T21:58:13+01:00 To do this, we examined cross-sensory consistency (across faces and odors) in the perception of masculinity and femininity in men and women, and how consistency is influenced by the use of artificial fragrance. Heres the four pieces of information we need to know: Given the results of the t-test, we can write up our results in APA something like this: The research question was whether there was a difference in student grades between Anastasias and Bernadettes classes. #3 An independent samples t-test showed that the 5.48 mean difference between the tutors student was statistically significant (t [31] = 2.12, p = .043, d = .74). << The package provides type-3 ANOVA output with degrees of freedom corrected F-tests for fixed-effects, which makes the package unique in open source implementations of mixed models. /S /URI >> /Producer (Acrobat Distiller 8.1.0 \(Windows\)) endobj Understanding the New Statistics: Effect Sizes, Confidence Intervals, and Meta-Analysis. Seven studies met the inclusion criteria: four articles studied cancer patients, one examined post-surgical patients, and two analyzed community dwelling older adults. /Rotate 0 endobj /Dest (cite.bib26) 0000002753 00000 n We used a 2 (Expectation: teach/test) x 2 (Instructions: analogy/explicit) x 2 (Posttest: low-pressure/high-pressure) mixed-factor design, with repeated measures on the last factor. /C [0 1 0] Still applying such models may be challenging for a sensory practitioner due the challenges associated with the choosing the random effects, selecting an appropriate model, interpreting the results. New York: Taylor & Francis. American Psychological Association (2009). A Guide to Using Post Hoc Tests with ANOVA, How to Use the MDY Function in SAS (With Examples). /Type /StructTreeRoot /H /I Sometimes, people like to put the statistics inside a parentheses. Similarly, TPDTs of the medial joint line were significantly increased in symptomatic (MD: 12.19mm; 95% CI: 7.59, 16.79; d=1.31) and asymptomatic knee (MD: 7.64mm; 95% CI: 3.64, 11.64; d=1.31) compared to pain-free controls. P,Z2Us&kyT5Du`P)FRA}nN>bF*a0b-0'nj{YJpZ%]L /C [0 1 1] Usually, significance for this test is determined at = .001 because this test is considered highly sensitive. The intervention clearly had a larger effect on math scores than reading scores. /Metadata 3 0 R The objective of this study was to calculate the effect of Reiki therapy for pain and anxiety in randomized clinical trials. 11 0 obj 36 0 obj /H /I /Type /Annot The overall 2 indicates that our model accounts for approximately 11.4% of the variability in math scores and treatment accounts for 17.5%. /Border [0 0 0] /RBGroups [] /URI (http://www.frontiersin.org/Psychology/about) 31-38, Pain Management Nursing, Volume 15, Issue 4, 2014, pp. WebWhen your SPSS output provides you with a significance level that consists of a string of zeroes (e.g., p = .000), the rule is: Drop the last zero and change it to a 1, and write p < << /A << WebWe report the F -statistic from a repeated measures ANOVA as: F (df time, df error) = F -value, p = p -value. The following video details 7 common errors that folks make when reporting statistical results. endobj /Rect [421.848 731.586 512.355 739.59] << Partial eta squared values should be reported with caution, and Levine and Hullett (2002) recommend reporting eta or omega squared rather than partial eta squared. My results may be statistically significant but they are not practically significant. Review score information can be presented in different formats. >> However, very few studies explored how geographical locations are correlated with dietary environmental footprints. The importance of research results is often assessed by statistical significance, usually that the p-value is less than 0.05. If you're using SPSS 27 or higher, you can opt to include effect size estimates with your ANOVA analysis. Conclusions:during SWDs FC and PC are strongly coupled and drive OC, while at the same time the influence of Hp to FC is diminished. Get started with our course today. Other common tests include the chi-square (2) and t-test. endobj /PageMode /UseOutlines /Border [0 0 0] /Category [/Export] /URI (http://www.frontiersin.org) /T1_3 61 0 R The concept of sphericity, for all intents and purposes, is the repeated measures equivalent of homogeneity of variances. << What if I told you that I had developed a new weight-loss pill and that the difference between the average weight loss for people who took the pill and the those who took a placebo was statistically significant? >> << Sitting posture may contribute to spinal pain. Local field potentials were recorded for eight hours in 23 WAG/Rij rats in the Frontal (FC), Parietal PC), Occipital Cortex (OC) and in the hippocampus (Hp). 12 0 obj << Even though the reading and math scores were measured on two different scales, we can directly compare the relative effect of the treatment using effect sizes: The results show that the average reading scores in the treated and control groups differ by approximately 0.22 standard deviations while the average math scores differ by approximately 0.92 standard deviations. endstream Here, we investigated the impact of artificial fragrances on the assessment of biologically relevant information in human body odor. >> 40 0 obj >> /Border [0 0 0] << << endobj Well, if we ran through the calculations, we would have ended up with a result of F(2, 15) = 1.504, p = .254, for the independent ANOVA. Effect sizes were calculated for all studies using Cohens d statistic. Ictally, a strong decrease in coupling strength was found between Hp and FC, as well as a large increase bidirectionally between PC and FC and unidirectionally from FC and PC to OC, and from FC to Hp over all epochs. /Event /Print If you have any questions, you can email OnLine@Ingrams.com, or call 816.268.6402. It measures the proportion of variance explained by a given variable of endobj The following table shows the results of a two-way ANOVA using exercise and gender as factors and weight loss as the response variable: We can calculate the partial eta squared for gender and exercise as follows: We would conclude that the effect size for exercise is very large while the effect size for gender is quite small. In order to complete this computation, you must also know how to compute each sum of squares (deviations from the mean), which can be a time-consuming process, especially with larger data sets. Learn more about us. We can interpret this to mean that about 14.75% of the variance unexplained by effects other than female is explained by the female effect. (2013). Nowadays, partial eta squared is widely cited as a measure of effect size. In some situations, accounting for 5% of the variability in an outcome could be very important and in other situations accounting for 30% may not be. However, we would otherwise report the above findings for this example exercise study as: There was a statistically significant effect of time on exercise-induced fitness, F(2, 10) = 12.53, p = .002. 0000000616 00000 n 27 0 obj 2 0 obj Z-Scores and the Standard Normal Distribution. The size of the effect tells us about the practical significance. /Dest (cite.bib1) /Subtype /Link One tip I strongly recommend when writing up your results is to read Educational and Psychological Measurement, 64(6) 916-924, Thompson, B. Twenty-five healthy participants, seated at a workstation without backrest, completed four, 15-min typing tasks: A)Upright with forearm-support; B)Upright without forearm-support; C)Slumped with forearm-support; D)Slumped without forearm-support. /Subtype /Link /ExportState /ON For our results, omitting the Subjects and Total rows, we have: which is similar to the output produced by SPSS. Your email address will not be published. /S /URI The results of the inferential test, including what test was performed, the test value and degrees of freedom, p-value, and effect size. endobj /Order [] /URI (http://www.frontiersin.org/Psychology) /H /I /C [0 1 1] 2 is a less biased variation of 2 that is equivalent to the adjusted R-squared. Do the rates of graduation among certain state universities differ by degree type? /Marked true /Subtype /Link tH7rt /H /I /Subtype /Link PPTs did not change from baseline. Algina, J., H. J. Keselman, and R. D. Penfield. !qvJ.?~_p(w6v:/?e,dp.7LeV@1,F8Q7_tq3n: As before, there are several different formulas that can be used. /Dest (cite.bib18) Many will also be familiar with the fact that r2, which is often termed the coefficient of determination, is equal to the proportion of the total variation in one of the variables that can be predicted or explained on the basis of its linear relationship with the other variable (see, e.g., Hays, 1963, p. 505). 6Yq NhE\$-*'&5=G4>`yu/Fw}tW\i}EcH\4{sJ6y)u-nEe^JjrADNn&"^M_hb=v25e|Anbmc7Dv^P*S6BY_~2vvhN2]-ry~,+Bm]f\?TGI%t>T,FC6ZO=k Vg{n}+}G=y}. Cultural practices may either enhance or interfere with evolved preferences as predicted by culturegene coevolution theory. << >> /Border [0 0 0] Tables and figures provide an overview of the structure and present post hoc analysis. Anyway, the use of a standardized scale allows us to assess of practical significance. /Border [0 0 0] /Rect [461.196 311.223 478.194 321.684] Kline, R. B. /Subtype /Link Partial eta square: Partial eta square ( 2) shows how much variance is explained by the independent variable. endobj CONTACT US. However, most statistical programmes, such as SPSS Statistics, will report the result of a repeated measures ANOVA in tabular form. |bh: uhK)4`1q`Rha@=g)edqRR%JB2IxA&iq8yojhq Put a space before and after a mathematical operator (e.g., <<212eac8fdaa823448c2b7b32360dd907>]>> In the past, they have been confused in the research literature. /Subject (Effect sizes are the most important outcome of empirical studies.) /Type /Annot 30 0 obj /A << /Subtype /Link Both of these measures concern the entire model. endobj 28 0 obj endstream Participants in the teach/analogy and teach/explicit groups practiced golf putting with the expectation of teaching putting to another participant, and analogy instructions or explicit instructions, respectively. The eta squared (2) is an effect size often reported for an ANOVA F-test. Design: Intercept+FathEduc he multivariate 2 = .186 indicates that approximately 19% of multivariate variance of the dependent variables is associated with the group factor. >> I have used Stata terminology, of course. /Last 71 0 R /Rect [437.4 747.687 512.283 755.736] /Creator (LaTeX with hyperref package) "sZXz )J*!6e Nz endobj HT[S6~BWf2,I/i]/_#^vZ`-# C3A Ill take two bottles and a large order of french fries to go!. /Rect [436.842 311.223 456.09 321.684] /Subtype /Link /C [0 1 0] A difference of 1.5 standard deviations is obviously large, and a difference of 0.1 standard deviations is obviously small. #4 Anastasias students #2 (M = 74.53, SD = 9.00, n = 15) #4 cont. >> /Type /Annot To test this, we recruit 30 men and 30 women to participate in an experiment in which we randomly assign 10 of each to follow a program of either no exercise, light exercise, or intense exercise for one month. /Font << Starting with computing this value by hand, we can again use a formula. /Dest (cite.bib43) /GS3 56 0 R We can write up our results (not the exercise example), where we have included Mauchly's Test for Sphericity as: Mauchly's Test of Sphericity indicated that the assumption of sphericity had been violated, 2(2) = 22.115, p < .0005, and therefore, a Greenhouse-Geisser correction was used. >> As a result, many authors refer to all of the above as just Delta. /Border [0 0 0] Patients with knee OA were less accurate (MD: 7.80%; 95% CI: 15.32, 0.27; d=0.52) recognizing images of their symptomatic knee. /H /I >> /ParentTreeNextKey 1 /H /I /URI (http://www.frontiersin.org/Cognition/archive) /H /I /Border [0 0 0] >> We therefore alert researchers in education and psychology to this reporting inaccuracy. If you would like a brief introduction using the GUI, you can watch a demonstration on Statas YouTube Channel: Most older papers and many current papers do not report effect sizes. /Contents [44 0 R 45 0 R 46 0 R 47 0 R 48 0 R 49 0 R 50 0 R 51 0 R] American Psychologist, 54, 594-604, Receive email notifications of new blog posts, Chuck Huber, Director of Statistical Outreach, Cautionary note on reporting eta-squared values from multifactor ANOVA designs, Just released from Stata Press: A Gentle Introduction to Stata, Revised Sixth Edition, Heteroskedasticity robust standard errors: Some practical considerations, Just released from Stata Press: Microeconometrics Using Stata, Second Edition. Indeed, Kline envisaged that researchers might report values of both 2 and partial 2 in their research publications, but this is surely likely to confuse rather than enlighten their readers. WebThe editorial policies of several prominent educational and psychological journals require that researchers report some measure of effect size along with tests for statistical significance. For our exercise-training example, the illustration below shows that after taking away SSsubjects from SSw we are left with an error term (SSerror) that is only 8% as large as the independent ANOVA error term. Participants in the Group A scored significantly higher (M = 1.23, SD = 0.81) than Group B (M = 0.52, SD = 0.10)., Recognizing Components of an APA-Style Statistical Report. << /T1_7 65 0 R 0000002652 00000 n We could repeat the same analyses for the reading scores using the following commands: None of the t- or F-statistics for reading scores were statistically significant at the 0.05 level. /Type /Annot /T1_8 66 0 R endobj However, the variability of CNP contents and stoichiometry of terrace wall soil aggregates and the path by which they are influenced have received little attention and are still uncertain. /Border [0 0 0] When presented with a choice between two products with equal average review scores but different variances, participants chose as if outlier review scores were discounted when scores were presented in the disaggregated format. endstream Partial eta-squared is where the the SSsubjects has been removed from the denominator (and is what is produced by SPSS): So, for our example, this would lead to a partial eta-squared of: Similar to the other ANOVA tests, each level of the independent variable needs to be approximately normally distributed. The key is that we include all four pieces of information as specified above, that the information is correct, and that the information is presented in a logical order based on how we test hypotheses. Put a space before and after a mathematical operator (e.g., minus, plus, greater than, less than). endobj 3 0 obj >> However, nowadays it is commonly used by statisticians in the context of correlational research that examines the role of classification variables determined in advance of the research project rather than treatment variables that are under experimental control. 45 0 obj Or what if I told you that the difference in weight loss was not statistically significant the p-value was only 0.06 but the average difference over the year was 20 pounds? 0000008324 00000 n endobj /Type /OCG +:aBA#;|Aob~ /Type /Page endobj If the dependent variable is distributed in, Recent commentators have arrived at different positions with regard to the usefulness of classical 2 and partial 2. << Ongoing support to address committee feedback, reducing revisions. Task-D caused higher UT and LT RMS-EMG (P<0.02) than other tasks. A Guide to Using Post Hoc Tests with ANOVA, Your email address will not be published. Use the partial -argument to compute partial eta squared values: eta_sq(fit, partial = TRUE) #> as.factor (e42dep) as.factor (c172code) c160age #> 0.281257128 0.007876882 **For additional assistance with computing and interpreting the effect size for your analysis, attend the SPSS: ANOVA/MANOVA group session**. /Filter /FlateDecode endobj However, the correlation between female ratings of male facial and odor masculinity was not evident when assessing a fragranced body odor. /Annots [16 0 R 17 0 R 18 0 R 19 0 R 20 0 R 21 0 R 22 0 R 23 0 R 24 0 R 25 0 R /URI (http://www.frontiersin.org/Psychology/editorialboard) Participants rated pain every minute on a numerical rating scale (NRS). There was a significant effect of time on cholesterol concentration, F(1.171, 38) = 21.032, p < .0005. %PDF-1.4 % /Subtype /Link 24 0 obj Further analysis also indicated that differences in ratings of male odor masculinity between men with high and low levels of facial masculinity were not present in fragranced body odor samples. /Rect [44.226 25.689 118.578 34.602] << /C [0 1 0] /Kids [77 0 R 78 0 R] In this blog, I will walk you through recognizing components of an APA-style statistical report so that you will feel more confident reading, interpreting, and writing statistical reports. 505509; Sechrest & Yeaton, 1982). 44 0 obj /Length 826 Introduction to Statistics is our premier online video course that teaches you all of the topics covered in introductory statistics. Make sure that you have a space on either side of the equals sign. /C [0 1 0] endobj Calculating and reporting effect sizes to facilitate cumulative science: a practical primer for t-tests and ANOVAs =|QU&CC=9g13Gb{au &u.aHTW3ZSM3[oWd The highest dose of WIN increased the couplings strength from FC to Hp and from OC to PC during 4 and 2hr respectively in all intervals, and decreased the FC to PC coupling strength postictally in epoch 2. Would you buy my new pill? >> By default, programs like SPSS report partial eta squared values in the output of ANOVA tables. /Subtype /Link /Usage << Here is an example of what results might look like for a t-test: And here is an example for a chi-square test: These results should not be listed alone, but always explained. /Border [0 0 0] (1996) AERA Editorial Policies regarding Statistical Significance Testing: Three Suggested Reforms. /C [0 1 0] With other ANOVA analyses, partial eta squared is more appropriate to report. /Rect [522.243 732.855 551.235 759.849] /Type /Annot 0000004685 00000 n Track all changes, then work with you to bring about scholarly writing. /ParentTree 76 0 R /H /I In the special case when there are just two groups, can be, By definition, both the classical version of 2 as defined in Formula (1) and partial 2 as defined in Formula (6) vary between 0 and 1. >> In my examples above, you knew that 1 pound over the year is small and 20 pounds is large because you are familiar with human weights. Chronic knee OA is associated with increased TPDT for medial and lateral knee joint lines and decreased recognition accuracy performance which should be considered during treatment process. >> Some methodologists believe that effect sizes with confidence intervals should always be reported and that statistical hypothesis tests should be abandoned altogether; see Cumming (2012) and Kline (2013). By continuing you agree to the use of cookies. Copyright 2011 Elsevier Ltd. All rights reserved. /Type /Pages Generally, the effect size is listed after the p-value, so if you do not immediately recognize it, it might be an unfamiliar effect size. Beyond Significance Testing: Statistics Reform in the Behavioral Sciences. Because there is no control group in observational studies, Kline (2013) recommends reporting Glasss using the standard deviation for each group. << >> The generic estimator is known as eta-squared. /Keywords (effect sizes, power analysis, cohen's d, eta-squared, sample size planning) 35 0 obj These were originally devised for measuring effect sizes in factorial designs, but nowadays they have a variety of other applications. /Dest (cite.bib13) /A << /Dest (cite.bib18) << Levine and Hullett, A number of commentators have pointed out limitations of both 2 and partial 2 as measures of effect size (OGrady, 1982, Pedhazur, 1997, pp. https://www.frontiersin.org/articles/10.3389/fpsyg.2013.00863 endobj All content on IngramsOnline.com 2000-2023 Show-Me Publishing, Inc. 166168) just presented the two measures of effect size without explaining why one might be preferred to the other. Studies that used randomization and a control or usual care group, used Reiki therapy in one arm of the study, were published in 2000 or later in peer-reviewed journals in English, and measured pain or anxiety were included. uuid:fdd78f84-5b39-4b1c-a17f-a76a7d7de41c >> /Subtype /Link /Type /Annot /K [74 0 R 75 0 R] /Type /Annot /H /I /Dest (cite.bib7) We also showed that though not significant, the correlation coefficient between geographical locations and EFP (r=0.52) exceeded the coefficient between direct economic indicators and EFP (r=0.44/0.48), while both coefficients mentioned above were significantly higher than the coefficient between indirect economic indicators and EFP (r=0.32/0.31). How to use Statas effect-size calculator. After removing duplicates, 49 articles were examined and 12 articles received full review. /A << /A << /Rect [368.865 322.68 452.121 333.141] (1999). The term effect is most commonly associated with the use of different treatments in formal experimental research. endobj << In Section 4, I noted that both 2 and partial 2 have a logical upper bound of 1. The following table shows the results of a, Partial eta squared for gender: 15.8 / (15.8+89.2) =, Partial eta squared for exercise: 505.6 / (505.6+89.2) =, What is Face Validity? /Rect [315.954 322.68 342.267 333.141] >> >> Copyright 2023 Elsevier B.V. or its licensors or contributors. Letters of the English alphabet that represent a statistical value (such as t, F, and p) should be italicized; however, Greek letters representing statistical values (such as ) are generally not italicized. Partial 2 and partial 2 are like partial R-squareds and concern individual terms in the model. eta-squared They also provide a formula for converting that multivariate eta squared to a partial eta squared (1 - lambda^(1/s), with s as min (p, df-effect).). Funnily enough, however, in the book, the authors also say that IBM SPSS will produce the partial eta squared values. Thus, its important to know the subtle difference between eta squared and partial eta squared. ~5CJhKFH+E$(`K~ (aRH- /Subtype /Link WebIn one way ANOVAs, they come out the same, but in more complicated models, their values, and their meanings differ. An Introduction to the Two-Way ANOVA WIN causes dramatic network changes which have major consequences for the decrease of SWDs, the occurrence of convulsive seizures, and the normal cortico-cortical and cortico-hippocampal interactions.

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