Simplified Methods of fitting the truncated Negative Binomial Distribution: A model that allows for Non users

Retailers monitor customer buying-behaviour as a measure of their stores’ success. However, summary measures such as the total buying-behaviour provides little insight about individual-level shopping behaviour. Additionally, behaviour may evolve over time, especially in a changing environment like the Internet. This research developed a useful stochastic model for analysing period to period fluctuations in sales thereby generalizing the model proposed by Goodhardt and Ehrenberg to allow for nonbuyers of the product category. So as the composition of the customer population changes (e.g., as customers mature or as large numbers of new and inexperienced Internet shoppers enter the market), the overall degree of buyer heterogeneity that each store faces may change. A systematic bias in their simple negative binomial distribution [NBD] model is demonstrated. If the proportion of nonbuyers is large, the simple model will be wrong. As a result, frequent buyers often comprise the preferred target segment. We find evidence supporting the fact that people who visit a store more frequently are more likely to buy. We also gives explicit formula and directions that allow a moderately analyst to perform his own conditional trend analysis. KEYWORDS:  Buying Behaviour, Negative Binomial Distribution,  Heterogeneity, Conditional Trend Analysis

Survey Error: It’s Implication on Research and Possible Remedies

This paper identifies and describes the primary sources of survey error in mail surveys and some methods typically used to assess and quantify some of these sources of error. Four sources of survey error- sampling error, non coverage error, non-response error and measurement error were discussed. Descriptions of how each of these sources of error occurs in mail surveys are provided. The paper summarizes ways of reducing these errors, if they cannot be totally avoided. Keyword: survey error, sampling error, non-coverage error, non-response error, measurement error, true score model

Consumer Purchase Behaviour in a Frequently bought product Category: Investigation and measure of Brand loyalty.

Past research has predominantly relied on models without incorporating heterogeneity as part of their methodological tools. This research investigates different ways of modeling brand loyalty using a competing risk model that incorporate brand loyalty and study its time dependence. We introduce previous models by including switch-specific hazard functions, repeat purchases, marketing mix Variables, unobserved heterogeneity and mover- stage type loyalty. An empirical example based on household purchases of disposable products is provided to illustrate the modeling approach. Results indicate that ignoring heterogeneity will lead to biased inferences concerning time dependence of brand loyalty. Keywords: Heterogeneity, Mover-Stayer loyalty, Hazard function, and Marketing mi

Developed beverage from roselle calyx and selected fruits modulates β-cell function, improves insulin sensitivity, and attenuates hyperlipidaemia in diabetic rats

The aim of this study is to report the antidiabetic properties of a beverage developed from roselle calyx and selected fruits in male albino rats. The beverage was designed to contain 30% pawpaw (Carica papaya L.), 10% grapefruit (Citrus paradisi), 20% guava leaves (Psidium guajava L.) and 40% roselle calyx aqueous extracts. Four groups of five rats each were acclimatized on pelletized mouse chow for seven days, after which diabetes was induced by a single ip injection of alloxan in all groups except group 1, which served as control. Group 2 served as negative control while groups 3 and 4 were treated with the beverage at 2.5 and 5 ml/kg bw respectively. Food intake, body weight, and blood glucose levels were monitored. They were sacrificed by cervical dislocation after a 2 week treatment. Blood serum was analysed to evaluate insulin levels, β cell function, insulin resistance and lipid profile. Histological studies were carried out on pancreatic tissues. Treatment with both doses of the beverage led to a significant reduction (p < 0.05) in blood glucose, total cholesterol triglyceride, LDL and increased HDL levels. It also improved serum insulin levels, β cell function, reduced insulin resistance and restored pancreatic beta cells compared to the diabetic group. These antidiabetic properties may be as a consequence of modulation of the β-cell function, reduction of insulin resistance and preservation/restoration of β-cell integrity. However, treatment with the single dose showed signs of hyperinsulinaemia