{"id":572,"date":"2021-04-27T14:12:37","date_gmt":"2021-04-27T14:12:37","guid":{"rendered":"https:\/\/www.allendowney.com\/blog\/?p=572"},"modified":"2021-04-27T14:12:37","modified_gmt":"2021-04-27T14:12:37","slug":"old-optimists-and-young-pessimists","status":"publish","type":"post","link":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/","title":{"rendered":"Old optimists and young pessimists"},"content":{"rendered":"\n<p>Years ago I told one of my colleagues about my Data Science class and he asked if I taught Simpson&#8217;s paradox. I said I didn&#8217;t spend much time on it because, I opined, it is a mathematical curiosity unlikely to come up in practice. My colleague was shocked and dismayed because, he said, it comes up all the time in his field (psychology).<\/p>\n\n\n\n<p>Ever since then, I have been undecided about Simpson&#8217;s paradox. A lot of people think it&#8217;s important, but when I look for compelling examples, I find the same three stories over and over: <a href=\"https:\/\/en.wikipedia.org\/wiki\/Simpson%27s_paradox#Examples\">Berkeley admissions, kidney stones, and Derek Jeter&#8217;s batting average<\/a>. Yawn.<\/p>\n\n\n\n<p>But last week I found a more interesting example:<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>Between 2000 and 2018, real wages for full-time employees increased.<\/li><li>Over the same period, real wages decreased for people at every level of education.<\/li><\/ol>\n\n\n\n<p>If that seems impossible, <a rel=\"noreferrer noopener\" href=\"https:\/\/www.allendowney.com\/blog\/2021\/04\/15\/simpsons-paradox-and-real-wages\/\" target=\"_blank\">go read my article about it<\/a>.<\/p>\n\n\n\n<p>I also found an article (&#8220;<a href=\"https:\/\/arxiv.org\/abs\/1801.04385\">Can you Trust the Trend: Discovering Simpson&#8217;s Paradoxes in Social Data<\/a>&#8220;) where the authors search a dataset for instances of Simpson&#8217;s paradox and describe the ones they find.<\/p>\n\n\n\n<p>And that got me thinking about my old friend, the General Social Survey (GSS). So I&#8217;ve started searching the GSS for instances of Simpson&#8217;s paradox. I&#8217;ll report what I find, and maybe we can get a sense of (1) how often it happens, (2) whether it matters, and (3) what to do about it.<\/p>\n\n\n\n<p>I&#8217;ll start with examples where the x-variable is time. For y-variables, I use about 120 questions from the GSS. And for subgroups, I use race, sex, political alignment (liberal-conservative), political party (Democrat-Republican), religion, age, birth cohort, social class, and education level. That&#8217;s about 1000 combinations.<\/p>\n\n\n\n<p>Of these, about 10 meet the strict criteria for Simpson&#8217;s paradox, where the trend in all subgroups goes in the same direction and the overall trend goes in the other direction. On examination, most of them are not very interesting. In most cases, the actual trend is nonlinear, so the parameters of the linear model don&#8217;t mean very much.<\/p>\n\n\n\n<p>But a few of them turn out to be interesting, at least to me. For example, the following figure shows the fraction of respondents who think &#8220;most of the time people try to be helpful&#8221;, plotted over time, grouped by decade of birth. The markers show the percentage in each group during each interval; the lines show local regressions.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"648\" height=\"360\" src=\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1.jpg\" alt=\"\" class=\"wp-image-578\" srcset=\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1.jpg 648w, https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1-300x167.jpg 300w, https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1-486x270.jpg 486w\" sizes=\"auto, (max-width: 648px) 100vw, 648px\" \/><\/figure>\n\n\n\n<p>Within each group, the trend is positive: apparently, people get more optimistic about human nature as they age. But overall the trend is negative. Why? Because of generational replacement. People born before 1940 are substantially more optimistic than people born later; as old optimists die, they are being replaced by young pessimists.<\/p>\n\n\n\n<p>Based on this example, we can go looking for similar patterns in other variables. For example, here are the results from a related question about fairness.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"648\" height=\"360\" src=\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/fair_vs_year_by_cohort10.jpg\" alt=\"\" class=\"wp-image-579\" srcset=\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/fair_vs_year_by_cohort10.jpg 648w, https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/fair_vs_year_by_cohort10-300x167.jpg 300w, https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/fair_vs_year_by_cohort10-486x270.jpg 486w\" sizes=\"auto, (max-width: 648px) 100vw, 648px\" \/><\/figure>\n\n\n\n<p>Again, old optimists are being replaced by young pessimists. <\/p>\n\n\n\n<p>For a similar question about trust, the results are a little more chaotic:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"648\" height=\"360\" src=\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/trust_vs_year_by_cohort10.jpg\" alt=\"\" class=\"wp-image-580\" srcset=\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/trust_vs_year_by_cohort10.jpg 648w, https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/trust_vs_year_by_cohort10-300x167.jpg 300w, https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/trust_vs_year_by_cohort10-486x270.jpg 486w\" sizes=\"auto, (max-width: 648px) 100vw, 648px\" \/><\/figure>\n\n\n\n<p>Some groups are going up and others down, so this example doesn&#8217;t meet the criteria for Simpson&#8217;s paradox. But it shows the same pattern of generational replacement.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Old conservatives, young liberals<\/h2>\n\n\n\n<p>Questions related to prohibition show similar patterns. For example, here are the responses to a question about whether pornography should be illegal.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"648\" height=\"360\" src=\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/pornlaw_vs_year_by_cohort10.jpg\" alt=\"\" class=\"wp-image-581\" srcset=\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/pornlaw_vs_year_by_cohort10.jpg 648w, https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/pornlaw_vs_year_by_cohort10-300x167.jpg 300w, https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/pornlaw_vs_year_by_cohort10-486x270.jpg 486w\" sizes=\"auto, (max-width: 648px) 100vw, 648px\" \/><\/figure>\n\n\n\n<p>In almost every group, support for banning pornography has increased over time. But recent generations are substantially more tolerant on this point, so overall support for prohibition is decreasing.<\/p>\n\n\n\n<p>The results for legalizing marijuana are similar.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"648\" height=\"360\" src=\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/grass_vs_year_by_cohort10.jpg\" alt=\"\" class=\"wp-image-582\" srcset=\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/grass_vs_year_by_cohort10.jpg 648w, https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/grass_vs_year_by_cohort10-300x167.jpg 300w, https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/grass_vs_year_by_cohort10-486x270.jpg 486w\" sizes=\"auto, (max-width: 648px) 100vw, 648px\" \/><\/figure>\n\n\n\n<p>In most groups, support for legalization has gone down over time; nevertheless, through the power of generational replacement, overall support is increasing.<\/p>\n\n\n\n<p>So far, I think this is more interesting than Derek Jeter&#8217;s batting average. More examples coming soon!<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Years ago I told one of my colleagues about my Data Science class and he asked if I taught Simpson&#8217;s paradox. I said I didn&#8217;t spend much time on it because, I opined, it is a mathematical curiosity unlikely to come up in practice. My colleague was shocked and dismayed because, he said, it comes up all the time in his field (psychology). Ever since then, I have been undecided about Simpson&#8217;s paradox. A lot of people think it&#8217;s important,&#8230;<\/p>\n<p class=\"read-more\"><a class=\"btn btn-default\" href=\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/\"> Read More<span class=\"screen-reader-text\">  Read More<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[1],"tags":[26,82],"class_list":["post-572","post","type-post","status-publish","format-standard","hentry","category-uncategorized","tag-general-social-survey","tag-simpsons-paradox"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v26.5 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Old optimists and young pessimists - Probably Overthinking It<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Old optimists and young pessimists - Probably Overthinking It\" \/>\n<meta property=\"og:description\" content=\"Years ago I told one of my colleagues about my Data Science class and he asked if I taught Simpson&#8217;s paradox. I said I didn&#8217;t spend much time on it because, I opined, it is a mathematical curiosity unlikely to come up in practice. My colleague was shocked and dismayed because, he said, it comes up all the time in his field (psychology). Ever since then, I have been undecided about Simpson&#8217;s paradox. A lot of people think it&#8217;s important,... Read More Read More\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/\" \/>\n<meta property=\"og:site_name\" content=\"Probably Overthinking It\" \/>\n<meta property=\"article:published_time\" content=\"2021-04-27T14:12:37+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1.jpg\" \/>\n<meta name=\"author\" content=\"AllenDowney\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@AllenDowney\" \/>\n<meta name=\"twitter:site\" content=\"@AllenDowney\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"AllenDowney\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"3 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#article\",\"isPartOf\":{\"@id\":\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/\"},\"author\":{\"name\":\"AllenDowney\",\"@id\":\"https:\/\/www.allendowney.com\/blog\/#\/schema\/person\/4e5bfb2e9af6c3446cb0031a7bf83207\"},\"headline\":\"Old optimists and young pessimists\",\"datePublished\":\"2021-04-27T14:12:37+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/\"},\"wordCount\":640,\"publisher\":{\"@id\":\"https:\/\/www.allendowney.com\/blog\/#organization\"},\"image\":{\"@id\":\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#primaryimage\"},\"thumbnailUrl\":\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1.jpg\",\"keywords\":[\"general social survey\",\"Simpson&#039;s paradox\"],\"inLanguage\":\"en-US\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/\",\"url\":\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/\",\"name\":\"Old optimists and young pessimists - Probably Overthinking It\",\"isPartOf\":{\"@id\":\"https:\/\/www.allendowney.com\/blog\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#primaryimage\"},\"image\":{\"@id\":\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#primaryimage\"},\"thumbnailUrl\":\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1.jpg\",\"datePublished\":\"2021-04-27T14:12:37+00:00\",\"breadcrumb\":{\"@id\":\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#primaryimage\",\"url\":\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1.jpg\",\"contentUrl\":\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1.jpg\",\"width\":648,\"height\":360},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.allendowney.com\/blog\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Old optimists and young pessimists\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.allendowney.com\/blog\/#website\",\"url\":\"https:\/\/www.allendowney.com\/blog\/\",\"name\":\"Probably Overthinking It\",\"description\":\"Data science, Bayesian Statistics, and other ideas\",\"publisher\":{\"@id\":\"https:\/\/www.allendowney.com\/blog\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.allendowney.com\/blog\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\/\/www.allendowney.com\/blog\/#organization\",\"name\":\"Probably Overthinking It\",\"url\":\"https:\/\/www.allendowney.com\/blog\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.allendowney.com\/blog\/#\/schema\/logo\/image\/\",\"url\":\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2025\/03\/probably_logo.png\",\"contentUrl\":\"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2025\/03\/probably_logo.png\",\"width\":714,\"height\":784,\"caption\":\"Probably Overthinking It\"},\"image\":{\"@id\":\"https:\/\/www.allendowney.com\/blog\/#\/schema\/logo\/image\/\"},\"sameAs\":[\"https:\/\/x.com\/AllenDowney\",\"https:\/\/www.linkedin.com\/in\/allendowney\/\",\"https:\/\/bsky.app\/profile\/allendowney.bsky.social\"]},{\"@type\":\"Person\",\"@id\":\"https:\/\/www.allendowney.com\/blog\/#\/schema\/person\/4e5bfb2e9af6c3446cb0031a7bf83207\",\"name\":\"AllenDowney\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.allendowney.com\/blog\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/fb01b3a7f7190bea1bbf7f0852e686c2f8c03b099222df2ce4bc7926f15bcb43?s=96&d=mm&r=g\",\"contentUrl\":\"https:\/\/secure.gravatar.com\/avatar\/fb01b3a7f7190bea1bbf7f0852e686c2f8c03b099222df2ce4bc7926f15bcb43?s=96&d=mm&r=g\",\"caption\":\"AllenDowney\"},\"url\":\"https:\/\/www.allendowney.com\/blog\/author\/allendowney_6dbrc4\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Old optimists and young pessimists - Probably Overthinking It","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/","og_locale":"en_US","og_type":"article","og_title":"Old optimists and young pessimists - Probably Overthinking It","og_description":"Years ago I told one of my colleagues about my Data Science class and he asked if I taught Simpson&#8217;s paradox. I said I didn&#8217;t spend much time on it because, I opined, it is a mathematical curiosity unlikely to come up in practice. My colleague was shocked and dismayed because, he said, it comes up all the time in his field (psychology). Ever since then, I have been undecided about Simpson&#8217;s paradox. A lot of people think it&#8217;s important,... Read More Read More","og_url":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/","og_site_name":"Probably Overthinking It","article_published_time":"2021-04-27T14:12:37+00:00","og_image":[{"url":"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1.jpg","type":"","width":"","height":""}],"author":"AllenDowney","twitter_card":"summary_large_image","twitter_creator":"@AllenDowney","twitter_site":"@AllenDowney","twitter_misc":{"Written by":"AllenDowney","Est. reading time":"3 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#article","isPartOf":{"@id":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/"},"author":{"name":"AllenDowney","@id":"https:\/\/www.allendowney.com\/blog\/#\/schema\/person\/4e5bfb2e9af6c3446cb0031a7bf83207"},"headline":"Old optimists and young pessimists","datePublished":"2021-04-27T14:12:37+00:00","mainEntityOfPage":{"@id":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/"},"wordCount":640,"publisher":{"@id":"https:\/\/www.allendowney.com\/blog\/#organization"},"image":{"@id":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#primaryimage"},"thumbnailUrl":"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1.jpg","keywords":["general social survey","Simpson&#039;s paradox"],"inLanguage":"en-US"},{"@type":"WebPage","@id":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/","url":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/","name":"Old optimists and young pessimists - Probably Overthinking It","isPartOf":{"@id":"https:\/\/www.allendowney.com\/blog\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#primaryimage"},"image":{"@id":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#primaryimage"},"thumbnailUrl":"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1.jpg","datePublished":"2021-04-27T14:12:37+00:00","breadcrumb":{"@id":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#primaryimage","url":"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1.jpg","contentUrl":"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/helpful_vs_year_by_cohort10-1.jpg","width":648,"height":360},{"@type":"BreadcrumbList","@id":"https:\/\/www.allendowney.com\/blog\/2021\/04\/27\/old-optimists-and-young-pessimists\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.allendowney.com\/blog\/"},{"@type":"ListItem","position":2,"name":"Old optimists and young pessimists"}]},{"@type":"WebSite","@id":"https:\/\/www.allendowney.com\/blog\/#website","url":"https:\/\/www.allendowney.com\/blog\/","name":"Probably Overthinking It","description":"Data science, Bayesian Statistics, and other ideas","publisher":{"@id":"https:\/\/www.allendowney.com\/blog\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.allendowney.com\/blog\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/www.allendowney.com\/blog\/#organization","name":"Probably Overthinking It","url":"https:\/\/www.allendowney.com\/blog\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.allendowney.com\/blog\/#\/schema\/logo\/image\/","url":"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2025\/03\/probably_logo.png","contentUrl":"https:\/\/www.allendowney.com\/blog\/wp-content\/uploads\/2025\/03\/probably_logo.png","width":714,"height":784,"caption":"Probably Overthinking It"},"image":{"@id":"https:\/\/www.allendowney.com\/blog\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/x.com\/AllenDowney","https:\/\/www.linkedin.com\/in\/allendowney\/","https:\/\/bsky.app\/profile\/allendowney.bsky.social"]},{"@type":"Person","@id":"https:\/\/www.allendowney.com\/blog\/#\/schema\/person\/4e5bfb2e9af6c3446cb0031a7bf83207","name":"AllenDowney","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.allendowney.com\/blog\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/fb01b3a7f7190bea1bbf7f0852e686c2f8c03b099222df2ce4bc7926f15bcb43?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/fb01b3a7f7190bea1bbf7f0852e686c2f8c03b099222df2ce4bc7926f15bcb43?s=96&d=mm&r=g","caption":"AllenDowney"},"url":"https:\/\/www.allendowney.com\/blog\/author\/allendowney_6dbrc4\/"}]}},"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack-related-posts":[{"id":555,"url":"https:\/\/www.allendowney.com\/blog\/2021\/04\/15\/simpsons-paradox-and-real-wages\/","url_meta":{"origin":572,"position":0},"title":"Simpson&#8217;s paradox and real wages","author":"AllenDowney","date":"April 15, 2021","format":false,"excerpt":"I have good news and bad news. First the good news: after a decade of stagnation, real wages have been rising since 2010. The following figure shows weekly wages for full-time employees (source), which I adjusted for inflation and indexed so the series starts at 100. Real wages in 2019\u2026","rel":"","context":"In \"Simpson&#039;s paradox\"","block_context":{"text":"Simpson&#039;s paradox","link":"https:\/\/www.allendowney.com\/blog\/tag\/simpsons-paradox\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/simpson_wages6.png?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/simpson_wages6.png?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/04\/simpson_wages6.png?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":622,"url":"https:\/\/www.allendowney.com\/blog\/2021\/05\/25\/in-search-of-simpsons-paradox\/","url_meta":{"origin":572,"position":1},"title":"In Search Of: Simpson&#8217;s Paradox","author":"AllenDowney","date":"May 25, 2021","format":false,"excerpt":"Is Simpson's Paradox just a mathematical curiosity, or does it happen in real life? And if it happens, what does it mean? To answer these questions, I've been searching for natural examples in data from the General Social Survey (GSS). A few weeks ago I posted this article, where I\u2026","rel":"","context":"In \"general social survey\"","block_context":{"text":"general social survey","link":"https:\/\/www.allendowney.com\/blog\/tag\/general-social-survey\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/05\/image-10.png?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/05\/image-10.png?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/05\/image-10.png?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":596,"url":"https:\/\/www.allendowney.com\/blog\/2021\/05\/03\/simpsons-paradox-and-age-effects\/","url_meta":{"origin":572,"position":2},"title":"Simpson&#8217;s Paradox and Age Effects","author":"AllenDowney","date":"May 3, 2021","format":false,"excerpt":"As people get older, do they become more racist, sexist, and homophobic? To find out, you could use data from the General Social Survey (GSS), which asks questions like: Do you think there should be laws against marriages between Blacks\/African-Americans and whites?Should a man who admits[mfn]If you find the wording\u2026","rel":"","context":"In \"general social survey\"","block_context":{"text":"general social survey","link":"https:\/\/www.allendowney.com\/blog\/tag\/general-social-survey\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/05\/fepol_vs_age_by_cohort10.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/05\/fepol_vs_age_by_cohort10.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/05\/fepol_vs_age_by_cohort10.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":590,"url":"https:\/\/www.allendowney.com\/blog\/2021\/05\/01\/simpsons-paradox-and-education\/","url_meta":{"origin":572,"position":3},"title":"Simpson&#8217;s Paradox and Education","author":"AllenDowney","date":"May 1, 2021","format":false,"excerpt":"Is Simpson's paradox a mathematical curiosity or something that matters in practice? To answer this question, I'm searching the General Social Survey (GSS) for examples. Last week I published the first batch, examples where we group people by decade of birth and plot their opinions over time. In this article\u2026","rel":"","context":"In \"general social survey\"","block_context":{"text":"general social survey","link":"https:\/\/www.allendowney.com\/blog\/tag\/general-social-survey\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/05\/libath_vs_year_by_degree.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/05\/libath_vs_year_by_degree.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2021\/05\/libath_vs_year_by_degree.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":1618,"url":"https:\/\/www.allendowney.com\/blog\/2025\/10\/16\/simpsons-what\/","url_meta":{"origin":572,"position":4},"title":"Simpson&#8217;s What?","author":"AllenDowney","date":"October 16, 2025","format":false,"excerpt":"I like Simpson\u2019s paradox so much I wrote three chapters about it in Probably Overthinking It. In fact, I like it so much I have a Google alert that notifies me when someone publishes a new example (or when the horse named Simpson\u2019s Paradox wins a race). So I was\u2026","rel":"","context":"In \"epidemiology\"","block_context":{"text":"epidemiology","link":"https:\/\/www.allendowney.com\/blog\/tag\/epidemiology\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2025\/10\/image-1.png?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":1357,"url":"https:\/\/www.allendowney.com\/blog\/2024\/08\/23\/probably-the-book\/","url_meta":{"origin":572,"position":5},"title":"Probably the Book","author":"AllenDowney","date":"August 23, 2024","format":false,"excerpt":"Last week I had the pleasure of presenting a keynote at posit::conf(2024). When the video is available, I will post it here [UPDATE here it is]. https:\/\/www.youtube.com\/watch?v=YKMZIzYBgTk In the meantime, you can read the slides, if you don't mind spoilers. For people at the conference who don't know me, this\u2026","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2024\/08\/are_you_normal_windshield_wiper.gif?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2024\/08\/are_you_normal_windshield_wiper.gif?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2024\/08\/are_you_normal_windshield_wiper.gif?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/www.allendowney.com\/blog\/wp-content\/uploads\/2024\/08\/are_you_normal_windshield_wiper.gif?resize=700%2C400&ssl=1 2x"},"classes":[]}],"_links":{"self":[{"href":"https:\/\/www.allendowney.com\/blog\/wp-json\/wp\/v2\/posts\/572","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.allendowney.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.allendowney.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.allendowney.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.allendowney.com\/blog\/wp-json\/wp\/v2\/comments?post=572"}],"version-history":[{"count":6,"href":"https:\/\/www.allendowney.com\/blog\/wp-json\/wp\/v2\/posts\/572\/revisions"}],"predecessor-version":[{"id":585,"href":"https:\/\/www.allendowney.com\/blog\/wp-json\/wp\/v2\/posts\/572\/revisions\/585"}],"wp:attachment":[{"href":"https:\/\/www.allendowney.com\/blog\/wp-json\/wp\/v2\/media?parent=572"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.allendowney.com\/blog\/wp-json\/wp\/v2\/categories?post=572"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.allendowney.com\/blog\/wp-json\/wp\/v2\/tags?post=572"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}