The economic consequences of language proficiency have received increasing attention in recent years. Language skills play an important role in labour market performance, schooling, health care, consumption and investment (see an overview in Chiswick and Miller 2014). The existing literature predominantly studies the topic in the context of immigration. These studies focus on how the proficiency in local languages contributes to adult immigrants' labour market performance (Chiswick and Miller 1995, Dustman and Van Soest 2001, Bleakley and Chin 2004, Yao and Van Ours 2015), as well as the educational performance of immigrant children (Dustman et al. 2010, Geay et al. 2013, Ohinata and Van Ours 2012, 2013).
In a new paper, we study the educational consequences of language skills but instead of studying immigrant students, we investigate the effects of speaking dialects at home on standardised test scores (Yao et al. 2016). We refer to dialects as variations of the standard language across regions and regional languages in a country. Since immigrants speak different languages from natives, they are the obvious choice of group for studying the effects of language. However, immigrant students do not only differ from native students in terms of the spoken language, they also have different socio-economic and cultural backgrounds. In contrast, dialect-speaking students share a relatively homogeneous background to those who speak the standard language of the country. In this sense, our estimates are likely to capture purer language effects.
Dialects are an integral part of daily communication and widespread in many countries. Nonetheless, the existing economic literature on dialect is scarce. Grogger (2011, 2014) reports that non-standard speech patterns like African American and Southern American dialects are associated with lower wages in the US labour market. Our study also contributes to the literature that the disadvantage of dialect-speaking can be traced back to the early stages of life.
Dialects in the Netherlands
The predominantly spoken language of the Netherlands is Standard Dutch, originating in the urban areas of Noord-Holland, Zuid-Holland and Utrecht. Aside from Standard Dutch, the regional languages and dialects spoken in the Netherlands are remarkably diverse, including Frisian, Limburgish, and Low Saxon. Frisian, mostly spoken in the province of Friesland, is recognised as a separate language and promoted by the local government. It is also an official subject and can be an instruction medium in primary schools, except for some exempted schools in Friesland. Limburgish and Low Saxon also enjoy the status as “official regional languages” in related regions, although there is no clear regulation regarding government support. Other provinces also have dialects such as Brabantish, spoken in Noord-Brabant, or Zeelandic in Zeeland (see an overview in Driessen, 2005). Therefore, Standard Dutch is the only instruction medium in most provinces in the Netherlands.
In order to demonstrate how different Dutch dialects are from Standard Dutch, Table 1 summarizes the linguistic distances between Standard Dutch and various regional dialects (Van Bezooijen and Heeringa, 2006). Linguistic distances are measured by the Levenshtein distance, which is based on a comparison of the pronunciation of typical words in one dialect and in Standard Dutch. As shown in Table 1, Frisian stands out from the other dialects by having the largest Levenshtein distance, i.e. 37, followed by Limburgish. As a point of comparison, the Levenshtein distance between Standard Dutch and English is reported to be 63 (Isphording and Otten, 2013). Therefore, the distances between some Dutch dialects and Standard Dutch are likely to be non-negligible.
Table 1. Linguistic distances of between each dialect and Standard Dutch
Source: Van Bezooijen and Heeringa (2006)
Our data are from PRIMA, a large-scale biannual longitudinal survey for primary schools in the Netherlands. We use a repeated cross-section sample from 1998 to 2004 of native children in the 2nd grade, aged 5-6 years old. In the questionnaires, parents indicate what language their child speaks to either parent: Standard Dutch, dialects or Frisian, or other foreign languages. We consider a student to be dialect-speaking if he or she speaks a dialect or Frisian to either mother or father. Our main variables of interest are standard test scores on language and math by the PRIMA survey. The language test measures understanding of words and concepts such as first, last, many and few. The math test focuses on the sorting of objects, comparing numbers and counting.
Our data suggest that, on average, dialect speakers achieve lower test scores on both language and math compared to Dutch speakers. Girls have higher test scores than boys regardless of whether they speak dialects or not. Dutch-speaking girls, therefore, are the most advantaged group, while dialect-speaking boys have the lowest average scores. In addition, dialect speakers are more likely to have parents with lower educational attainment than Dutch speakers. The proportion of parents with university or higher degrees is around 10 percentage points higher for Dutch speakers than for dialect speakers.
Dialect-speaking and test scores
In order to study the potential impacts of dialect-speaking on test scores, OLS regressions are separately estimated, taking account of various individual and class/school level characteristics. In addition, we also control for school fixed effects in order to correct for potential bias that arises from potential self-sorting into schools. We find that speaking dialects with parents significantly decreases boys' language scores, by 0.079 standard deviations, but has no effect on girls' language scores. For the dialect-speaking effects on math scores, we do not find any significant effect once we control for individual characteristics. Moreover, our results indicate that the penalty of speaking dialects on boys' language scores increases with linguistic distance to Standard Dutch. An increase of 10 units in the linguistic distance will further decrease dialect-speaking boys' language scores by 0.025 standard deviations.
Spillover effects of dialect-speaking
Would classmates' dialect-speaking affect test scores? We also investigate the spillover effects of studying in a common environment with dialect speakers. As a proxy for the intensity of students' communication in dialects within a classroom, we calculate the share of dialect-speaking peers relative to the total number of peers in each class. Relying on random allocation of dialect speakers across classrooms in one grade, we can provide causal evidence that the share of dialect-speaking peers has no significant effect on Standard Dutch speakers' language scores or math scores, nor does it have any effect on dialect speakers’ language or math scores.
We find only a modest impact of speaking dialects on language performance among Dutch boys, but not Dutch girls. This can be related to different trajectories of language development between young boys and girls. We hypothesise that the dialect penalty on boys' academic performance would disappear at later stages of life. In addition, it is important to remember that our study cannot rule out the possibility that the educational consequences of language would be non-negligible in countries where the linguistic barriers experienced by dialect speakers or non-native speakers in general are larger. We leave investigations of these questions for future research.
Bleakley, H, and A Chin (2004), “Language skills and earnings: Evidence from childhood immigrants”, Review of Economics and Statistics 86(2), 481–496
Chiswick, B R, and P W Miller (1995), “The endogeneity between language and earnings: International analyses”, Journal of Labor Economics 13(2), 246–288
Chiswick, B R, and P W Miller (2014), “International migration and the economics of language”, in B R Chiswick and P W Miller (eds.), Handbook of the Economics of Immigration, pp. 211–269, Elsevier
Driessen, G (2005), “In Dutch? Usage of Dutch regional languages and dialects”, Language, Culture and Curriculum 18, 271–285
Dustmann, C, and F Fabbri (2003), “Language proficiency and labour market performance of immigrants in the UK”, Economic Journal 113(489), 695–717
Dustmann, C, S Machin, and U Schonberg (2010), “Ethnicity and educational achievement in compulsory schooling”, Economic Journal 120, 272–297
Dustmann, C, and A van Soest (2001), “Language fluency and earnings: Estimations with misspecified indicators”, Review of Economics and Statistics 83(4), 663–674
Geay, C, S McNally, and S Telhaj (2013), “Non-native speakers of English in the classroom: What are the effects on pupil performance?”, Economic Journal 123, 281–307
Grogger, J (2011), “Speech patterns and racial wage inequality”, Journal of Human Resources 46, 1–25
Grogger, J (2014), “Speech and wages”, University of Chicago
Isphording, I E, and S Otten (2013), “The costs of Babylon? Linguistic distance in applied economics”, Review of International Economics 21 (2), 354-369
Ohinata, A, and J C van Ours (2012), “Young immigrant children and their educational attainment”, Economics Letters 116(3), 288–290
Ohinata, A, and J C van Ours (2013), “How immigrant children affect the academic achievement of native Dutch children?”, Economic Journal 123, 308–326
Van Bezooijen, R, and W Heeringa (2006), “Intuitions on linguistic distance: geographically or linguistically based?” In T Koole, J Nortier, and B Tahitu (eds.), Vijfde sociolingu ̈ıstische conferentie, pp. 77–87, Eburon Uitgeverij BV
Yao, Y, and J C van Ours (2015), “Language skills and labor market performance of immigrants in the Netherlands”, Labour Economics 34, 76–85
Yao, Y, A Ohinata and JC van Ours (2016), “The educational consequences of language proficiency for young children”, CEPR, Discussion Paper 11183