508 research outputs found
How does the franchisor’s choice of different control mechanisms affect franchisees’ and employee-managers’ satisfaction?
Satisfaction of franchisees and employee-managers affects the overall performance of a franchise system. We argue that different actors in the same franchise system need to be treated in different ways. The franchisor’s choice of control mechanisms affects the satisfaction of franchisees and employee-managers differently. Drawing on data from the largest German franchise system, we show that the effectiveness of different control mechanisms depends on actor type and experience. Outcome control leads to higher satisfaction among franchisees and employee-managers, while behavior control enhances employee-managers’ satisfaction. Thereby, outcome control leads to higher satisfaction among more experienced franchisees, while behavior control enhances both highly and lowly experienced employee-managers’ satisfaction. Our results suggest that franchisors face a dilemma: On the one hand, behavior control is associated with high costs and has no impact on franchisees’ satisfaction at all. On the other hand, it might still be necessary to prevent franchisees from behaving opportunistically
Identification and Classification of Stratospheric Sudden Warming Events
Analysis of northern hemisphere stratospheric data from 1978-2011 is used to identify and classify Stratospheric Sudden Warming events. A total of 41 events are identified during this 33 year period, resulting in an average occurrence rate of 1.24 events/year. No significant variation in the rate is observed during the period analyzed. The average temperature increase during an SSW event is 12 K and the average duration is 32 days. Each identified event is classified as either a vortex displacement or split event and the ratio of displacement to split events is found to be 0.86
The Hitchhiker\u27s Guide to the Long Tail: The Influence of Online-Reviews and Product Recommendations on Book Sales - Evidence from German Online Retailing
Exploring the long tail phenomenon, we empirically analyze whether online reviews, discussion forums, and product recommendations help to reduce search costs and actually alter the sales distribution in online book retailing. We have collected a data set containing 320,248 observations for 40,031 different books at Amazon.de, each assigned to one of 111 different product categories in our sample. By adopting an innovative approach, we provide the first long tail conversion model for the German online market, based on publicly available sales data. Our results indicate that online reviews and automated product recommendations reduce search costs by facilitating the identification of adequate books and the assessment of their quality. This highlights the relevance of information technology implementation as vital part of the marketing strategy
Specific Investments and Ownership Structures in Railways – An Experimental Analysis
We analyze the impact of different organizational structures on incentives to invest in railways: vertical integration, vertical separation, and a hybrid form. Economic theory predicts that vertical integration fosters socially optimal investment, whereas, due to potential hold-up problems, both vertical separation and hybrid forms cause severe underinvestment. We test these theoretical predictions in a laboratory experiment and find evidence that, in a vertically integrated environment, the level of investment in rolling stock and in rail infrastructure is roughly socially optimal. The complete absence of a discrepancy in our experimental results between vertical separation and the hybrid organisational structure, contradicting the predictions of model-theory, is surprising and can be attributed to the relatively high investments in the separated model. This contradiction might also be explained by the existence of social preferences.game theory, vertical separation, railways, experimental economics
Textile based dye-sensitized solar cells with natural dyes
Natural dyes extracted from hibiscus petals, elderberries and mallow flowers were investigated in dye-sensitized solar cells. Two approaches were followed: 1. Hybrid glass/fabric cells with titanium dioxide on glass as working electrode and a textile counter electrode; 2. hybrid fabric/glass cells with zinc oxide as working electrode on textile and a glass counter electrode. The zinc oxide layer on cotton was prepared by electroless deposition whereas the titanium dioxide coated glass electrodes were obtained directly from the manufacturer. In both cases the redox couple consisted of iodine / triiodide and the counter electrode was based on an electrically conductive fabric
Governance and strategy of entrepreneurial networks: an introduction
This special issue focuses on empirical and theoretical papers that help us to better understand the strategy and governance of entrepreneurial networks, such as franchise chains, alliances, and cooperative networks. The following central themes are covered: (I) Which formal governance mechanisms do entrepreneurial networks use in order to reduce transaction cost/agency cost and to increase strategic value? (II) What is the role of relational governance mechanisms (such as information exchange and social ties) for the performance outcomes in franchise chains and cooperatives? (III) Which alliance strategies do entrepreneurial firms pursue to realize a competitive advantage, and what is the impact of resources and capabilities on performance outcomes of entrepreneurial firms. To address these issues, insights from organizational economics (transaction cost theory, agency theory, signaling theory), strategic management perspectives (resource-based, knowledge-based and organizational capabilities theory), entrepreneurship theory and the relational governance view are used
2008,01: Managing the evolution of cooperation
Management scholars have long stressed the importance of evolutionary processses
for inter-firm cooperation but have mostly missed the promising opportunity
to incorporate ideas from evolutionary theories into the analysis of collaborative
arrangements. In this paper, we first present three rules for the evolution of cooperation
– kinship selection, direct reciprocity, and indirect reciprocity. Second, we
apply our theoretical considerations, enriched with ideas from cultural anthropology,
to the context of a specific and particularly attractive type of cooperative arrangement,
the franchise form of organization. Third, we provide a preliminary
empirical test with regards to conditions under which evolutionary modes can secure
cooperative behavior. We conclude by summarizing our results and deriving
fertile areas for further research
The use of CGM to identify type 1 diabetic patients with hypoglycemia problems and its impact for avoidance of biochemical hypoglycemia.
This cross-over study used a CGM system (DexCom SEVEN PLUS CGM).
In a randomized order, participants had either no access (CGM blind) or real
time access to current glucose data (CGM open). One objective was to analyze
if type 1 diabetic patients with hypoglycemia problems (at least one
episode requiring third party assistance) could be identifi ed by the use of the
blinded CGM data. We also analyzed the impact of CGM use on biochemical
hypoglycemia. Type 1 diabetic patients with hypoglycemia problems had
signifi cant longer diabetes duration (17.0 vs. 11.0 yrs.), a higher unawareness
score (4.0 vs. 2.0) and lower thresholds for detecting hypoglycemia (50.0
vs. 65.0 mg/dl) than patients without hypoglycemia problems. During the
blinded CGM phase patients with hypoglycemic problems had a signifi cant
longer duration of low glucose phases 248 vs. 153 minutes per day (p=.037;
<70 mg/dl) respectively 173 vs. 96 minutes per day (p=.041; <60 mg/dl). Area
under the receiver operating curve (ROC 0.72 p=.03) indicated a suffi cient
screening performance of the duration of low glucose periods (< 70 mg/dl)
for the identifi cation of patients with hypoglycemia problems. A cut-off of
170 minutes per day of time spend in the low glucose range had a sensitivity
of 75% and a specifi city of 70.3%; the positive predictive value was 52.9%,
the negative predictive value was 86.4%. A comparison of blind vs. open
CGM showed that time spend in a low glucose range could be signifi cantly
more reduced in patients with hypoglycemia problems than in patients without
hypoglycemia problems during CGM open (< 60 mg/dl; - 67.8 min per day
p=.040; < 50 mg/dl; -50.6 min per day, p=.038; < 40 mg/dl; -41.4 min. per day,
p=.03). This study shows that CGM has an unused potential for identifying
type 1 diabetic patients at risk for hypoglycemia problems in clinical practice
as well as for avoidance of biochemical hypoglycemia, which plays a pivotal
role for the development of hypoglycemia associated autonomic failure
The Influence of Diabetes-related Distress on Depression
Depressive disorders in diabetic patients are nearly twice as likely
compared to the non-diabetic population. There is evidence that patients’
perception of diabetes is a decisive aspect of this association. Therefore this
study prospectively investigates the role of patients’ perceived diabetesrelated
distress on incidence depression and recovery.
343 patients with type 1 diabetes completed the CES-D and the Problem
Areas in Diabetes Scale (PAID) at baseline and at the 6-month follow-up. A
CES-D score of ≥16 indicated elevated depressive symptoms. A PAID score
of ≥30 indicated elevated diabetes-related distress. Logistic regression
analyses were performed with recovery from and incidence of depressive
symptoms as dependent variables. Independent variable was diabetesrelated
distress adjusted for possible demographic (age, gender, BMI) and
medical confounders (diabetes duration, HbA1c, insulin pump therapy, and
late complications).
At baseline 130 patients (37.9%) reported elevated depressive symptoms
and 40 of these patients (30.8%) recovered 6 months later. Of the 213 patients
without elevated depressive symptoms, 27 (12.7%) had elevated depressive
symptoms 6 months later. Diabetes-related distress at baseline diminished
the chance to recover from elevated depressive symptoms by 64% (OR =
0.36, p<.05). In addition, the chance for incident depressive symptoms if
diabetes-related distress was present at baseline is 2.5 times more likely in
contrast to no diabetes-related distress at baseline (OR=2.5; p<.05). In both
analyses, no other variables reached a signifi cant infl uence.
It could be demonstrated that preventing diabetes-related distress is a
protective factor regarding the incidence of elevated depressive symptoms.
Furthermore, preventing diabetes-related distress supports the recovery
from already elevated depressive symptoms. This supports the notion that
diabetes per se is not a risk factor for depressive disorders but the perceived
emotional distress is
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