Essays on Social Media, Hiring Networks and Firm Performance

This dissertation includes three essays that examine the impact of information technology on organizational performance. In the first essay, we examine the impact of network structure in the hiring of IT versus non-IT labor on firm performance. We find that hiring IT workers from a structurally-diverse network of firms has a positive effect on firm productivity, while there is no similar effect for non-IT labor in general. We attribute this to the different nature of knowledge diffused through the two types of labor: IT labor enables the transfer of new and innovative firm practices which benefits from diversity, while non-IT labor flows are associated with implementation of organizational practices, which may benefit from hiring more employees with a common knowledge base. In the second essay, we examine the economic value of social media investments and identify the organizational complements. We argue that social media brings in large amounts of real-time data, requiring a sufficient amount of data analytical skills for organizations to effectively process the information and integrate it into organizational decision making. We find evidence that the value of social media investments is higher in firms with a larger pool of data analytic skills in the labor force. In addition, social media’s positive impact on firm performance extends beyond the marketing department, and is further increased when the data analytic skills are dispersed throughout the firm. In the third essay, we investigate whether startup firms’ use of social media is associated with increased success in raising venture capital. We find that an active social media presence and strong Twitter influence increase a startup’s chances of receiving more funding and from a larger pool of investors. Specifically, social media improves startup funding success through two channels: reducing the search cost for investors to discover new investment opportunities and providing an additional channel of information for investors to better evaluate startup quality

A theoretical foundation for program transformations to reduce cache thrashing due to true data sharing

AbstractCache thrashing due to true data sharing can degrade the performance of parallel programs significantly. Our previous work showed that parallel task alignment via program transformations can be quite effective for the reduction of such cache thrashing. In this paper, we present a theoretical foundation for such program transformations. Based on linear algebra and the theory of numbers, our work analyzes the data dependences among the tasks created by a fork-join parallel program and determines at compile time how these tasks should be assigned to processors in order to reduce cache thrashing due to true data sharing. Our analysis and program transformations can be easily performed by compilers for parallel computers

Attention or Appreciation? The Impact of Feedback on Online Volunteering

We examine how different types of feedback influence online volunteer contributions in the context of online consultations for college entrance applications, which requires the volunteer counselor and the person receiving help (the counselee) to be online at the same time. We investigate the impact of two types of feedback on volunteers’ participation: 1) appreciation, as reflected in the number of positive ratings received by a counselor from counselees; and 2) attention, as reflected in the readership of a counselor’s profile page. We find that appreciation encourages the volunteer to engage in more helping behavior, likely because it can activate the volunteer’s altruistic motivation. In contrast, attention discourages volunteers to offer more help, possibly because they feel they have accomplished enough or because they feel passed over when they receive a lot of attention but few requests for consultations. The findings suggest that platform designers should encourage appreciation from those helped and provide more nuanced feedback about attention

Conversation-oriented ASR with multi-look-ahead CBS architecture

During conversations, humans are capable of inferring the intention of the speaker at any point of the speech to prepare the following action promptly. Such ability is also the key for conversational systems to achieve rhythmic and natural conversation. To perform this, the automatic speech recognition (ASR) used for transcribing the speech in real-time must achieve high accuracy without delay. In streaming ASR, high accuracy is assured by attending to look-ahead frames, which leads to delay increments. To tackle this trade-off issue, we propose a multiple latency streaming ASR to achieve high accuracy with zero look-ahead. The proposed system contains two encoders that operate in parallel, where a primary encoder generates accurate outputs utilizing look-ahead frames, and the auxiliary encoder recognizes the look-ahead portion of the primary encoder without look-ahead. The proposed system is constructed based on contextual block streaming (CBS) architecture, which leverages block processing and has a high affinity for the multiple latency architecture. Various methods are also studied for architecting the system, including shifting the network to perform as different encoders; as well as generating both encoders' outputs in one encoding pass.Comment: Submitted to ICASSP202

Gender Difference in 2-Year Mortality and Immunological Response to ART in an HIV-Infected Chinese Population, 2006–2008

Since it was initiated in 2002, the China Free Antiretroviral Treatment (ART) Program has been progressing from an emergency response to a standardized treatment and care system. As of December 31, 2009, a total of 81,880 patients in 31 provinces, autonomous regions, and special municipalities received free ART. Gender differences, however, in mortality and immunological response to ART in this cohort have never been described.To understand whether women and men who enrolled in the China National Free ART Program responded equally well to the treatment.A retrospective analysis of the national free ART databases from June 2006-December 2008 was performed. HIV-infected subjects who were 18 years or older, ART naïve at baseline, and on a 3TC regimen enrolled in the program from June 1 to December 31, 2006, were included in this study, then followed up to 2 years.Among 3457 enrolled subjects who met the inclusion criteria, 59.2% were male and 40.8% female. The majority of the subjects were 19-44 years old (77%) and married (72%). Over the full 24 months of follow-up, the mortality rate was 19.0% in males and 11.4% in females (p = 0.0014). Males on therapy for 3-24 months were more likely to die than females (HR = 1.46, 95% CI: 1.04-2.06, p = 0.0307) after adjusting for baseline characteristics. Compared to men, women had higher CD4+ counts over time after initiating ART (p<0.0001).Our study showed that women had an overall lower mortality and higher CD4+ counts than men in response to ART treatment, which may be attributed to adherence, biological factors, social, cultural and economic reasons. Further study is needed to explore these factors that might contribute to the gender differences in mortality and immunological response to ART

Does Employer Brand Matter: An Empirical Study on Online Job Reviews, Social Media Usage and Firm Performance

In this study, we examine how employee-contributed job reviews and firm-managed social media posts jointly build up “employer brand” as an intangible asset and influence market valuation. Using large-scale datasets of job reviews, social media posts and firm performance, we study how employer band can create value distinct from overall corporate (consumer) branding. We find that more positive job ratings are associated with higher firm market value, particularly in labor-intensive industries and especially for positions which are harder to replace and have higher employee mobility. In addition, firms can complement this effect by posting more employee-related content on their social media pages. Overall, our results suggest that firms should have coordinated strategies across digital platforms, presenting a consistent employer brand, to maximize their market valuation

Are All Spillovers Created Equal? A Network Perspective on IT Labor Movements

This study aims to understand how characteristics of a firm’s hiring network affect firm productivity using an inter-firm hiring network constructed from individual job histories. We separate IT labor from non-IT labor and use the network characteristics constructed from the two types labor to understand how they affect firm performance. We find that hiring IT workers from a diverse set of firms can provide access to novel and non-redundant information, which can substantially improve firm productivity. Interestingly, we find the opposite for hiring non-IT labor. In fact, having a cohesive network of non-IT labor hires is instrumental for implementing complementary organizational practices that are different to transfer without frequent and repeated exposures. Together, these results demonstrate the importance of incorporating a network perspective in understanding the full impact of spillover effects from organizational hiring activities