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Nanooptics which describes the interaction of light with matter at the nanoscale, is a topic of great fundamental interest to physicists and engineers and allows the direct observation of quantum mechanical phenomena in action. This self-contained and extensively referenced text describes the underlying theory behind nanodevices operating in the quantum regime for use both in advanced courses and as a reference for researchers in physics, chemistry, electrical engineering, and materials science. Presenting an extensive theoretical toolset for design and analysis of nanodevices, the authors demonstrate the art of developing approximate quantum models of real nanodevices. The rudimentary mathematical knowledge required to master the material is carefully introduced, with detailed derivations and frequent worked examples allowing readers to gain a thorough understanding of the material. More advanced applications are gradually introduced alongside analytical approximations and simplifying assumptions often used to make such problems tractable while representative of the observed features.
Combustion is ubiquitous around us and in the technology that we depend on in our daily lives. To someone uninitiated in the field, observing the combustion process can produce emotions ranging from apathy, fear, boredom, conservatism, or caution to outright joy, including love and affection. Observing combustion is also a great source of fascination to many, in particular to scientists and engineers, who seek to understand the intricate relationships among the chemical, thermal, fluid dynamic, and other complex phenomena involved in the combustion process. The wide variety of fuel and oxidizers, operating conditions such as initial temperature, pressure, and concentrations, and combustor geometry configurations create virtually limitless combinations of combustion, observed visually as flame(s). For example, flames of gaseous, liquid, and solid fuels share many similarities, but they also exhibit their own unique features. Flames do not depict all of their features naturally, and thus researchers employ various diagnostics techniques, often laser-based, to measure one or more characteristics, which can also unravel the mysteries of soot, nitric oxide, and carbon oxide formation, and/or help address various safety-related issues such as flame flashback, flame blow-off, flame noise, etc. The ultimate goal of such explorations is to develop clean combustion systems that are fuel agnostic, highly efficient, and, most importantly, environmentally friendly, i.e., they produce low or very low levels of harmful emissions, including greenhouse gas emissions. This chapter presents simple canonical flames, free from the complexities of most practical combustion systems, to offer insight into the key phenomena. This chapter is divided into eight sections, each covering a different aspect of laboratory-scale flames.
The long, sporadic prehistory of this book began when Vikas read former Chief Minister of Manipur Radhabinod Koijam's op-ed on the Naga peace process in the Hindu after finishing his undergraduate studies. Writing a few months after the 2001 Census, Koijam drew attention towards, among other things, the discrepancies between different estimates of Nagaland's area and population. An interview of Nagaland's Chief Minister Neiphiu Rio by Sanjoy Hazarika published in the Statesman in December 2005, when Vikas was back in the academe, briefly revived the interest in Nagaland's statistics. In the interview, Rio admitted that his state's headcount was flawed. This study though had to wait until 2011, when Ankush came across a news report on the ‘contraction’ of Nagaland's population between 2001 and 2011.
Our preliminary analysis of the census data suggested that conventional factors could not explain Nagaland's abnormal demographic trajectory. While it became clear that non-demographic factors were key to understanding changes in Nagaland's population and that fieldwork and archival research were indispensable, the scope of the study remained ill-defined until after we visited the state to obtain a first-hand idea of the scale and nature of the statistical ‘mess’. Our conversations through the second half of 2011 coalesced into short-term project proposals at our respective institutions, Institute of Economic Growth and Azim Premji University. Little did we know then that Nagaland's statistics would engage us for the better part of the following decade and take us through the length and breadth of the state.
Studying maps was not part of our original plan. During our visits to Nagaland, we found a great diversity of maps on the walls of government offices and private establishments. Discussions with government officials and civil society leaders complicated the picture further. Finally, after a senior bureaucrat effectively told us that the estimate of the state's area was a state secret, we decided to examine maps and area statistics and realised that they were essential for conducting population censuses and sample surveys.
Until the late nineteenth century, when the British established control over parts of the Naga Hills1 and Ao Nagas were exposed to Christianity, the Naga society was non-literate. Unlike other parts of the Indian subcontinent that had prior exposure to collection of information by premodern states and could influence early colonial statistical categories and practices to some extent (Peabody 2001; Guha 2003), Nagas were first exposed to statistics only in the late nineteenth century beginning with the record-keeping of the Baptist Church and colonial administration. Yet within a generation, numbers and written documents became key ingredients of political debates in the Naga Hills and began to play an important role in the Naga nationalist discourse.
The Memorandum on the Naga Hills to the Simon Commission (1929), the foundational document of the Naga political history (Timeline 2.1), contains arguments based on government statistics and statistical comparisons. The memorandum notes,
[O]ur population numbering 1,02,000 is very small in comparison with the population of the plains districts in the Province [Assam], and any representation that may be allotted to us in the Council will be negligible and will carry no weight whatsoever … if we are forced to enter the Council of the majority all these rights [private rights recognised by the British Government] may be extinguished by an unsympathetic Council, the majority of whose number is sure to belong to the Plain District … we should not be thrust to the mercy of the people who could never subjugate us, but leave us alone to determine ourselves as in ancient times. (Chasie 2000: Appendix A.I)
The adjusted 1921 population of the Naga Hills district was 158,801 after accounting for the transfer of the Diger Mauza from Kohima subdivision to North Cachar subdivision in 1923 (NSA, 2:587). Furthermore, according to the 1921 Census, the population of the Naga tribes of Assam, including Nagas outside the Naga Hills district, was 220,619 (Marten 1923: 160). The members of the Naga Club who submitted the memorandum belonged to Angami (including Eastern Angami, that is, Chakhesang), Kacha Naga, Kuki, Sumi, Lotha and Rengma tribes. The population of the speakers of the corresponding ‘vernaculars’ was 121,759 (ibid.: 98). The figure quoted in the memorandum is, however, close to 102,402, the 1901 Census population estimate (Allen 1902: 32; McSwiney 1912: Table II).
Electoral contests are usually viewed in terms of strategies for winning a plurality or majority of votes. These contests can also be waged at the stages of the choice of electoral system and delimitation of constituencies. The latter involves the choice of rules governing delimitation and the demarcation of constituencies under the rules, both of which are susceptible to political interference. The manipulation of demographic data with the objective of influencing delimitation is another possibility.
A stable constitution and an independent judiciary have meant that the basic structure of India's electoral system is very difficult to change. As a result, political manoeuvring has been restricted to delimitation and electoral contests. Interstate delimitation was frozen in the 1970s and will remain so until the first census taken after 2026. The extended suspension of the interstate delimitation, which was aimed at avoiding interstate conflicts, has shifted the locus of redistributive conflicts to sub-state levels of aggregation and opened up space for intercommunity and inter-district contests. The 2002 delimitation that was supposed to redistribute parliamentary and assembly constituencies within states and also redistribute seats between scheduled and non-scheduled communities on the basis of the 2001 Census faced strong opposition in the country's ethnogeographic periphery dominated by the Scheduled Tribes (STs) and religious minorities (Maps 1.2 and 7.4). In Assam, Arunachal Pradesh, Jammu and Kashmir, Jharkhand, Manipur and Nagaland, politically influential communities/ regions forced the postponement of the delimitation until after the first census taken after 2026. In Chhattisgarh, Meghalaya, Sikkim and Uttarakhand, the delimitation criteria had to be relaxed in favour of the indigenous communities. In all these cases, concessions were achieved through constitutional amendments, amendments to delimitation and other relevant legislation or through a departure from the prescribed guidelines at the time of demarcation of constituencies. It is also noteworthy that the government delayed the release of Post-Enumeration Survey (PES) for the 2001 Census ‘to avoid needless political controversies’ while delimitation was in progress (Bose 2008: 16). In other words, it feared that dissatisfied communities/administrative units could demand adjustments based on the errors identified by the PES. Indeed, some of the aggrieved communities demanded that the Delimitation Commission should adjust census population estimates using the PES data (CPO et al. 2003).
The poverty headcount ratio for Nagaland estimated using National Sample Survey Office (NSSO) data varies abnormally over the years. Until 2004–5, Nagaland reported one of the lowest rural poverty rates in the country, but by the end of the decade, it was among the states with relatively high poverty rates. A substantial improvement in the reported human development and other socio-economic indicators for Nagaland (Agrawal and Kumar 2012b: Table 1), which is largely rural, seem inconsistent with growing rural poverty in the recent decade when the state has enjoyed relatively peaceful conditions after a long period of armed conflict. Another puzzling feature of NSSO surveys is the increase in the share of tribal households in its samples for Nagaland from 85 per cent in the 50th round (1993–4) to 96 per cent in the 66th round (2009–10), even though the composition of the corresponding census population has remained stable over the years (Table 4.12).
This chapter analyses the quality of household sample survey data collected by the NSSO. There are several reasons for restricting the focus to NSSO surveys. First, most national level household surveys either do not cover states in India's ethno-geographic periphery or cover them irregularly. The NSSO regularly covers peripheral states including Nagaland. We will argue that even the surveys such as the NSSO that regularly cover these states do not have sufficiently representative samples to generate reliable estimates. The data deficit – the non-availability and/ or the poor quality of data – affects developmental outcomes through its impact on policymaking. Second, the NSSO has been conducting surveys in Nagaland since the 1970s. This provides a reasonably long time series to examine how changes in the sampling design affect survey statistics. Third, other household surveys launched after 1991 do not share sufficient information about the sampling design. In comparison, the NSSO survey reports discuss sampling design in greater detail. Last but not the least, the NSSO data are the most comprehensive and widely used sources of household level statistics for India.
NSSO surveys cover a wide range of household characteristics. We will restrict our attention to monthly per capita consumer expenditure (MPCE), which is of singular importance as it is used to estimate the incidence of poverty.
[I]n the Reserve Bank [of India] we are handicapped by the reliability of some of the basic data that we need to use in policy calculations.
There should be no fear of being small in number—as a village, town or District, State or as a people. It is not how many we are that matters, but who we are that really counts. As Nagas we should be known for our courage, integrity and unity, irrespective of our numbers.
—Rio (2014: 37–8)
We should judge results, not by statistics or the amount of money spent, but by the quality of human character that is evolved.
—Jawaharlal Nehru's ‘Foreword’ to Elwin (1959)
In the run-up to the 2011 Census in Nagaland, the government released several advertisements that framed the exercise in moral terms. One of the posters showed a Naga idol exhorting people to give correct responses to census questions with the following words: ‘My future must be built on the truth – Correct Census means strong future!’ (Figure 7.1). Politicians (Rio 2010b: 108; 2011: 73–4), civil society leaders (interviews, 24 November 2012 and 8 April 2013, Dimapur; see also CPO & Ors. vs. UoI & Ors. 2006), bureaucrats (Naga IAS officer, interview, 25 June 2013, Kohima) and church leaders (speeches, Clean Election Campaign, 19 September 2012, Hotel Japfu, Kohima) viewed the manipulation of government statistics as a reflection of individual and collective moral failings and used words such as ‘honesty’, ‘greed’, ‘integrity’ and ‘shame’ to describe the problem. The chief minister argued that the government was helpless in absence of ‘a conscious social decision based on moral values and ethical grounds’ (Rio 2010b: 108). He invoked Naga-Christian values and appealed to all concerned:
to ensure that the Census 2011 [is] conducted properly with truth and honesty. We cannot afford to leave behind for our younger generations a legacy of falsehood and deception. A society cannot be built on the foundation of falsehood and expect to prosper. It goes against our traditional as well as Christian values. We must demonstrate in the right way our traditional qualities of honesty, and uphold the dignity of the Naga people by counting ourselves correctly. (Rio 2011: 73–4)
A few states/union territories of India reported a decrease in population immediately after decolonisation. The 1941 Census of India overestimated the population of Punjab and Bengal, the two provinces of British India that were directly affected by partition in 1947. In these provinces communities tried to boost their numbers to secure greater political representation and, eventually, a favourable alignment of borders in the event of partition. The overcount was corrected in 1951, resulting in the contraction of the reported population (GoI 1954a: 5; Natarajan 1972: vii). While the coverage error (error in the overall headcount) was corrected in 1951, content error (error in the sub-classification of headcount) persisted in Punjab. The 1951 Census data on language were affected by communal competition in Punjab, the Patiala and East Punjab States Union (PEPSU) and Himachal Pradesh. Two union territories, the Andaman and Nicobar Islands (1941–51) and Daman and Diu (1951–61), also reported negative growth rates in the decade of decolonisation. Nagaland's experience is quite different though.
Nagaland registered the highest growth in population across India between 1981 and 2001 (Figures 4.1A and 4.2). However, in 2011, it reported the lowest growth rate as its population contracted in the absence of epidemical disease, famine, natural calamity, war and any major change in its political status and socio-economic conditions. This was the first time that a state in independent India experienced a contraction in population. This chapter examines Nagaland's demographic somersault – decades of unusually high growth of the reported population followed by its sudden contraction (Figure 4.1B).
Errors in a census can be classified into two broad categories, namely, coverage and content errors. Coverage error ‘refers to either an under‐count or over‐count of units owing to omissions of persons/housing units or duplication/ erroneous inclusion, respectively’, whereas content error ‘pertains to the error in the characteristics that are reported for the persons or housing units that are enumerated’ (UN Secretariate 2010: 10). Content errors affect the distributional accuracy of the headcount, whereas coverage errors affect the accuracy of the overall headcount. Errors in census may not necessarily affect the overall headcount if they are restricted to the composition of population.
[In Nigeria,] the census figures became strong political weapons rather than statistical data to be used for planning for socio-economic development.
—Adepoju (1981: 35)
In a severely divided society … an election can become an ethnic head count … a census needs to be ‘won’. So the election is a census, and the census is an election.
—Horowitz (2000: 196)
Over the past two centuries, the deep and multifaceted relation between statistics and statecraft has emerged as one of the defining features of states across the world. Modern states depend on statistics for the planning and evaluation of interventions. The growing size and complexity of operations undertaken by states have deepened their dependence upon statistics. Bureaucratisation and technocratisation of policymaking as well as the growing capacity of non-state actors to challenge government policies have also pushed states towards statistics.
The relationship between state and statistics is not merely instrumental though. Given their intimate relation with the origin and evolution of modern states, statistics are integral to the self-imagination of states and, also, to how they are imagined by people. In its earlier eighteenth-century sense, statistics was ‘a set of administrative routines needed to describe a state and its population’ (Desrosieres 1998: 16), a description of the state by and for itself (ibid.: 147). By the early nineteenth century, almost all Western countries had established statistical offices (Tooze 2003: 2; Urla 1993: 821) as ‘national statistics’ had come to be seen ‘as one of the vital attributes of the nation-states then under construction or seeking to assert themselves’ (Desrosieres 2013: 10). The quality of statistics produced by a country began to be seen as an attribute of its socio-economic and political development, with advanced economies and liberal democracies being associated with better statistical systems (Porter 1995: 80; see also Urla 1993: 821). Around the same time, statistics also began to be seen as enablers of public interest. And the census ‘became less concerned with what the people could be obliged to do for the state and more concerned with what the state could do for them’ (Coleman 2012: 335) amidst an emerging ‘shift towards willing participation [in state-sponsored data collection efforts] on the part of the respondents’ (Bookman 2013: 51; see also Starr 1987: 12; Prewitt 2010: 239).
In the run-up to the February 2018 Assembly Elections, the website of Nagaland's chief electoral officer hosted two different types of constituency maps. One was legally correct with regard to the external borders (Maps 3.1 and 3.3[b]), and the other was factually correct with regard to constituency borders and the location of polling booths in the disputed territory between Assam and Nagaland (Maps 3.2 and 3.3[a]). This is not the first time though that the Nagaland government has published mutually inconsistent maps of constituencies (Agrawal and Kumar 2017a: Map 5). Moreover, election maps are not the only conflicting maps released by the state government. Maps published by the Census (Maps 3.8 and 3.10E) and the Nagaland GIS and Remote Sensing Centre (NGISRSC) (Maps 3.5–3.7) also differ with respect to the external borders. In some cases, even maps published on the same sheet are mutually inconsistent (Map 3.4). The diversity of government maps is supplemented by a wide variety of maps published by civil society organisations, non-governmental organisations, insurgent groups and partisans of independence, which are often displayed in government offices as well.
When we first visited Nagaland about eight years ago, we were struck by this multiplicity of inconsistent maps and estimates of area of the state. Unable to find any authoritative estimate of area, one of us interviewed a senior official incharge of border affairs in Kohima (25 June 2013). Initially, the official denied the cartographic diversity, but later argued that maps released by different departments varied with their footprints. So, the education department's map of schools differs from the health department's map of dispensaries. This can at best explain the differences within the borders of the state but not the differences between maps in terms of the external borders. The official finally admitted that there might be discrepancies due to border disputes but expressed an inability to share the estimate of Nagaland's area as the matter was sub judice (SoA vs. UoI & Ors. 1988) and referred the interviewer to existing government publications. Another official argued that geographic information system (GIS) maps were not entirely accurate for forested, hilly terrain (interview, 19 September 2012, Kohima). However, the maps of Nagaland are more erroneous around the Assam–Nagaland border that runs through plains and foothills, where the vegetation is not dense.