National Panel Survey 2014-2015 - Tanzania

Abstract
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The main objective of the NPS is to provide high-quality household-level data to the Tanzanian government and other stakeholders for monitoring poverty dynamics, tracking the progress of the Five Year Development Plan (FYDP) II poverty reduction strategy and its predecessor plans, and evaluating the impact of other major, national-level government policy initiatives. As an integrated survey covering a number of different socioeconomic factors, it compliments other more narrowly focused survey efforts, such as the Demographic and Health Survey (DHS) on health, the Integrated Labour Force Survey (ILFS) on labour markets, the Household Budget Survey (HBS) on expenditure, and the National Sample Census of Agriculture (NSCA). Secondly, as a panel household survey in which the same households are revisited over time, the NPS allows for the study of poverty and welfare transitions and the determinants of living standard changes.

Geographic coverage
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National

Analysis unit
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Households; Individuals

Universe
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The universe includes all households and individuals in Tanzania with the exception of those residing in military barracks or other institutions.

Kind of data
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Sample survey data [ssd]

Sampling procedure
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The NPS sample was refreshed for NPS 2014/2015. Longitudinal surveys tend to suffer from bias introduced by households leaving the survey over time (i.e. attrition). Although the NPS maintains a highly successful recapture rate (roughly 96% retention at the household level), minimizing the escalation of this selection bias, a refresh of longitudinal cohorts is typically done to ensure proper representativeness of estimates while maintaining a sufficient primary sample to maintain cohesion within panel analysis. Additionally, the refreshing of a longitudinal sample realigns the sample with any changes in administrative boundaries, demographic shifts, or updated population information. In the case of Tanzania, a newly completed Population and Housing Census (PHC) in 2012 providing updated population figures, along with changed in administrative boundaries, emboldened an opportunity to realign the NPS sample. Similar to the sample in NPS 2008/2009, the sample design for the “Refresh Panel” allows analysis at four primary domains of inference, namely: Dar es Salaam, other urban areas on mainland Tanzania, rural mainland Tanzania, and Zanzibar. The sample design is a stratified two-stage design. The design consists of 51 design strata (identified in the data as ‘strataid’) corresponding to a rural/urban designation for each of the 26 regions; however, Dar es Salaam is pure urban and therefore constitutes only one stratum. The allocation across the design strata was informed by the last round of the NPS and seeks to balance multiple survey objectives and maximize precision given survey parameters. The intended sample design consisted of a new selection of 3,360 households corresponding to 420 EAs from the latest PHC in 2012. This new cohort in NPS 2014/2015 will be maintained and tracked in all future rounds between national censuses. A nationally representative sub-sample was selected to continue as part of an “Extended Panel”. This “Extended Panel” allowed general comparison of sample groups and monitoring indicator comparability.

Mode of data collection
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Other [oth]

Cleaning operations
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Additional data cleaning was conducted as the final stage of the data processing. Further adjustment of the data post-entry was conducted under the principle of absolute certainty where adjustments must be evidence-based and correction values true beyond a reasonable doubt. As such, the resulting final data files may still contain some inconsistencies and outliers. Handling of these values is thus left entirely to the data user. Throughout the data processing system, versions of the data are archived at all key steps and all checking and cleaning syntax documented and archived.

{'Abstract': "本数据集的主要目标是为坦桑尼亚政府及其他利益相关方提供高质量的 household-level 数据，以监测贫困动态，追踪五年发展计划（FYDP II）减贫战略及其前身计划的发展进程，并评估其他重大国家级政府政策倡议的影响。作为一个涵盖众多不同社会经济因素的综合性调查，它补充了其他更为专注于特定领域的调查努力，例如健康领域的人口与健康调查（DHS）、劳动力市场领域的综合劳动力调查（ILFS）、支出领域的家庭预算调查（HBS）以及国家农业抽样调查（NSCA）。其次，作为一个面板家庭调查，其中相同的家庭会在不同时间被重新访问，NPS 允许研究贫困和福利的转移以及生活水平变化的决定因素。

地理覆盖范围：

全国

分析单位：

家庭；个人

调查范围：

包括坦桑尼亚境内所有家庭和个人，除非居住在军事营房或其他机构。

数据类型：

样本调查数据 [ssd]

抽样程序：

NPS 样本在 2014/2015 年进行了刷新。纵向调查往往因家庭在调查过程中退出而产生的偏差（即流失）而受到困扰。尽管 NPS 在家庭层面的重新捕获率非常高（大约 96% 的保留率），但这最大限度地减少了这种选择偏差的升级，通常对纵向队列进行刷新以确保估计值的适当代表性，同时保持足够的主要样本以维持面板分析内的凝聚力。此外，刷新纵向样本将样本与任何行政边界变化、人口变动或更新的人口信息对齐。在坦桑尼亚的情况下，2012 年完成的人口与住房普查（PHC）提供了更新的人口数据，以及行政边界的变更，这为重新对齐 NPS 样本提供了机会。与 NPS 2008/2009 年的样本设计类似，'刷新面板' 的样本设计允许在四个主要推断领域进行分析，即：达累斯萨拉姆、坦桑尼亚大陆的其他城市地区、农村坦桑尼亚大陆以及桑给巴尔。样本设计是一个分层两阶段设计。设计包括 51 个设计层（在数据中标识为 'strataid'），对应于 26 个地区中的每个地区的农村/城市标识；然而，达累斯萨拉姆是纯城市，因此仅构成一个层。在设计层之间的分配是基于 NPS 的最后一轮调查，旨在平衡多个调查目标并最大化在调查参数下的精度。预期的样本设计包括从最新的 2012 年 PHC 中选择 3,360 个家庭，对应于 420 个 EA。这个新的队列将在所有未来的普查之间被维护和追踪。选择了一个全国代表性的子样本，以继续作为“扩展面板”的一部分。这个“扩展面板”允许对样本组进行一般比较并监测指标的可比性。

数据收集方式：

其他 [oth]

数据清理操作：

在数据处理的最后阶段进行了额外的数据清理。在数据录入后进行的进一步数据调整遵循绝对确定性的原则，即调整必须是基于证据的，且纠正值必须在合理怀疑之外是真实的。因此，生成的最终数据文件可能仍然包含一些不一致和异常值。对这些值的处理完全留给数据使用者。在整个数据处理系统中，所有关键步骤的数据版本都会存档，所有检查和清理语法都会进行记录和存档。"}