Visual comparison of two data sets: Do people use the means and the variability?
Author(s) / Creator(s)
Kramer, Robin S. S.
Telfer, Caitlin G. R.
Towler, Alice
Abstract / Description
In our everyday lives, we are required to make decisions based upon our statistical intuitions. Often, these involve the comparison of two groups, such as luxury versus family cars and their suitability. Research has shown that the mean difference affects judgements where two sets of data are compared, but the variability of the data has only a minor influence, if any at all. However, prior research has tended to present raw data as simple lists of values. Here, we investigated whether displaying data visually, in the form of parallel dot plots, would lead viewers to incorporate variability information. In Experiment 1, we asked a large sample of people to compare two fictional groups (children who drank ‘Brain Juice’ versus water) in a one-shot design, where only a single comparison was made. Our results confirmed that only the mean difference between the groups predicted subsequent judgements of how much they differed, in line with previous work using lists of numbers. In Experiment 2, we asked each participant to make multiple comparisons, with both the mean difference and the pooled standard deviation varying across data sets they were shown. Here, we found that both sources of information were correctly incorporated when making responses. Taken together, we suggest that increasing the salience of variability information, through manipulating this factor across items seen, encourages viewers to consider this in their judgements. Such findings may have useful applications for best practices when teaching difficult concepts like sampling variation.
Keyword(s)
informal inferential reasoning comparing groups mean difference pooled standard deviation variabilityPersistent Identifier
Date of first publication
2017-07-21
Journal title
Journal of Numerical Cognition
Volume
3
Issue
1
Page numbers
97–111
Publisher
PsychOpen GOLD
Publication status
publishedVersion
Review status
peerReviewed
Is version of
Citation
Kramer, R. S. S., Telfer, C. G. R., & Towler, A. (2017). Visual comparison of two data sets: Do people use the means and the variability? Journal of Numerical Cognition, 3(1), 97–111. https://doi.org/10.5964/jnc.v3i1.100
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jnc.v3i1.100.pdfAdobe PDF - 284.99KBMD5: 1ca1817dcb147696d902f0f259acfb4f
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There are no other versions of this object.
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Author(s) / Creator(s)Kramer, Robin S. S.
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Author(s) / Creator(s)Telfer, Caitlin G. R.
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Author(s) / Creator(s)Towler, Alice
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PsychArchives acquisition timestamp2018-11-21T11:42:42Z
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Made available on2018-11-21T11:42:42Z
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Date of first publication2017-07-21
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Abstract / DescriptionIn our everyday lives, we are required to make decisions based upon our statistical intuitions. Often, these involve the comparison of two groups, such as luxury versus family cars and their suitability. Research has shown that the mean difference affects judgements where two sets of data are compared, but the variability of the data has only a minor influence, if any at all. However, prior research has tended to present raw data as simple lists of values. Here, we investigated whether displaying data visually, in the form of parallel dot plots, would lead viewers to incorporate variability information. In Experiment 1, we asked a large sample of people to compare two fictional groups (children who drank ‘Brain Juice’ versus water) in a one-shot design, where only a single comparison was made. Our results confirmed that only the mean difference between the groups predicted subsequent judgements of how much they differed, in line with previous work using lists of numbers. In Experiment 2, we asked each participant to make multiple comparisons, with both the mean difference and the pooled standard deviation varying across data sets they were shown. Here, we found that both sources of information were correctly incorporated when making responses. Taken together, we suggest that increasing the salience of variability information, through manipulating this factor across items seen, encourages viewers to consider this in their judgements. Such findings may have useful applications for best practices when teaching difficult concepts like sampling variation.en_US
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Publication statuspublishedVersion
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Review statuspeerReviewed
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CitationKramer, R. S. S., Telfer, C. G. R., & Towler, A. (2017). Visual comparison of two data sets: Do people use the means and the variability? Journal of Numerical Cognition, 3(1), 97–111. https://doi.org/10.5964/jnc.v3i1.100en_US
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ISSN2363-8761
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Persistent Identifierhttps://hdl.handle.net/20.500.12034/1246
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Persistent Identifierhttps://doi.org/10.23668/psycharchives.1438
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Language of contenteng
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PublisherPsychOpen GOLD
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Is version ofhttps://doi.org/10.5964/jnc.v3i1.100
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Keyword(s)informal inferential reasoningen_US
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Keyword(s)comparing groupsen_US
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Keyword(s)mean differenceen_US
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Keyword(s)pooled standard deviationen_US
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Keyword(s)variabilityen_US
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Dewey Decimal Classification number(s)150
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TitleVisual comparison of two data sets: Do people use the means and the variability?en_US
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DRO typearticle
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Issue1
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Journal titleJournal of Numerical Cognition
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Page numbers97–111
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Volume3
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Visible tag(s)Version of Record