An analysis of some mistakes, miracles and myths in supplier selection

This paper analyzes some consequences of formal methods and procedures for supplier selection. It argues that many mistakes and miracles may occur in frequently used procedures. Practical examples are given. In the analysis it turns out that preventing these unwanted effects from occurring may be tackled by methodological improvements. Some examples and guidelines for these are given as well. But another important point lies in the perspectives of the actors in supplier selection: governments and industry policy makers, purchasers, suppliers and (management) researchers. The analysis shows that these different actors often operate from quite different and sometimes conflicting attitudes, assumptions and principles. On the one hand this analysis leads to the conclusion that using some sort of formal approach for supplier selection may be necessary. On the other hand it clarifies the criticism on such an approach and the difficulties associated with its use. The paper concludes with recommendations and implications for policy makers, researchers, and practitioners

Buying bundles: the effects of bundle attributes on the value of bundling

We consider the situation in which a buyer has to find the optimal degree of bundling for buying goods and services. From a review of the literature we develop attributes associated with bundling. Each of these attributes has an effect on the value of a bundle. Combined, the attributes determine the value of a bundle. We describe how the various attributes of a bundle contribute to the value of a bundle given the context of the buying situation. Based on interviews, a further analysis of bundle attributes and their effects on the bundle value is provided. The results of this analysis can be used to assist in finding the optimal degree of bundling

Circadian and Ultradian Rhythms of Free Glucocorticoid Hormone Are Highly Synchronized between the Blood, the Subcutaneous Tissue, and the Brain

Total glucocorticoid hormone levels in plasma of various species, including humans, follow a circadian rhythm that is made up from an underlying series of hormone pulses. In blood most of the glucocorticoid is bound to corticosteroid-binding globulin and albumin, resulting in low levels of free hormone. Although only the free fraction is biologically active, surprisingly little is known about the rhythms of free glucocorticoid hormones. We used single-probe microdialysis to measure directly the free corticosterone levels in the blood of freely behaving rats. Free corticosterone in the blood shows a distinct circadian and ultradian rhythm with a pulse frequency of approximately one pulse per hour together with an increase in hormone levels and pulse height toward the active phase of the light/dark cycle. Similar rhythms were also evident in the subcutaneous tissue, demonstrating that free corticosterone rhythms are transferred from the blood into peripheral target tissues. Furthermore, in a dual-probe microdialysis study, we demonstrated that the circadian and ultradian rhythms of free corticosterone in the blood and the subcutaneous tissue were highly synchronized. Moreover, free corticosterone rhythms were also synchronous between the blood and the hippocampus. These data demonstrate for the first time an ultradian rhythm of free corticosterone in the blood that translates into synchronized rhythms of free glucocorticoid hormone in peripheral and central tissues. The maintenance of ultradian rhythms across tissue barriers in both the periphery and the brain has important implications for research into aberrant biological rhythms in disease and for the development of improved protocols for glucocorticoid therapy

Incorporating supplier’s learning in buying bundles

We consider the situation in which a purchaser can either buy a large quantity at the same time or sequentially in a number of smaller lots. Buying in a number of smaller lots obviously increases transaction costs. But buying in smaller lots provides the opportunity to the supplier to learn by discovering the true costs of supplying every lot. This is especially interesting for purchasers (and suppliers) operating in markets where little is known about the true costs of supply or where small margins require very accurate estimates. Using optimal learning modeling we analyze the effect of incorporating learning possibilities for suppliers into the bundling decision of the purchasing manager. We show that incorporating learning into bundles can have a significant effect on the total cost of acquisition. These results show purchasing managers the importance of an underestimated effect in bundling decisions: the learning effec

Influence of tumour stage at breast cancer detection on survival in modern times: population based study in 173 797 patients

Objectives To assess the influence of stage at breast cancer diagnosis, tumour biology, and treatment on survival in contemporary times of better (neo-)adjuvant systemic therapy. Design Prospective nationwide population based study. Setting Nationwide Netherlands Cancer Registry. Participants Female patients with primary breast cancer diagnosed between 1999 and 2012 (n=173 797), subdivided into two time cohorts on the basis of breast cancer diagnosis: 1999-2005 (n=80 228) and 2006-12 (n=93 569). Main outcome measures Relative survival was compared between the two cohorts. Influence of traditional prognostic factors on overall mortality was analysed with Cox regression for each cohort separately. Results Compared with 1999-2005, patients from 2006-12 had smaller (≤T1 65% (n=60 570) v 60% (n=48 031); P<0.001), more often lymph node negative (N0 68% (n=63 544) v 65% (n=52 238); P<0.001) tumours, but they received more chemotherapy, hormonal therapy, and targeted therapy (neo-adjuvant/adjuvant systemic therapy 60% (n=56 402) v 53% (n=42 185); P<0.001). Median follow-up was 9.8 years for 1999-2005 and 3.9 years for 2006-12. The relative five year survival rate in 2006-12 was 96%, improved in all tumour and nodal stages compared with 1999-2005, and 100% in tumours ≤1 cm. In multivariable analyses adjusted for age and tumour type, overall mortality was decreased by surgery (especially breast conserving), radiotherapy, and systemic therapies. Mortality increased with progressing tumour size in both cohorts (2006-12 T1c v T1a: hazard ratio 1.54, 95% confidence interval 1.33 to 1.78), but without a significant difference in invasive breast cancers until 1 cm (2006-12 T1b v T1a: hazard ratio 1.04, 0.88 to 1.22), and independently with progressing number of positive lymph nodes (2006-12 N1 v N0: 1.25, 1.17 to 1.32). Conclusions Tumour stage at diagnosis of breast cancer still influences overall survival significantly in the current era of effective systemic therapy. Diagnosis of breast cancer at an early tumour stage remains vita