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101.
Gabriella Phiri Peter Mumba Agnes Mangwera 《International Journal of Consumer Studies》2006,30(6):527-532
A survey was conducted in Lilongwe city urban markets in Malawi, to assess the quality of cooking oil used for frying potato chips. Purposive sampling was performed to come up with respondents who were using vegetable oils. A stratified random sampling was used to select the 32 informal food processors who were interviewed using a structured questionnaire. Oil samples were collected from the most commonly used brand of oil. Fifteen respondents were selected and these were divided into three categories of five: those who were not reusing the oil, those who were reusing the oil and those who were preparing potato chips and chicken in the same oil, for chemical analysis. The preliminary results showed that while the majority (59.4%) of the informal food processors discarded the oil after 1 day, 3.1% discarded it after 4 days and another 12.5% after 3 days. A larger proportion of the respondents (40.6%) used the leftover oils at home, 37.5% kept it in oil bottles, 3.1% kept it in plastic papers for reuse the following day. Also, most respondents (57%) indicated dark colour as the sign of oil deterioration, 29% discarded the oil after noticing foam formation while 8.2% and 6.1% said they discarded the oil after noticing a bad smell and food absorbing the oils respectively. A physical observation of the various oils showed that for most of the respondents (34%), the oils were dark brown in colour, in 22%, the oils were slightly dark brown and 16%, the oils were brown. Foam formation was noticed in 13% of the respondents. It was also noted that 91% of the respondents had not been trained or briefed of food quality and safety issues. A chemical analysis of the oils showed high values of free fatty acids (range, 0.84–1.4112 compared with 0.42 in the fresh oil) and peroxide values (range 14.7–16.6 compared with 9.0 in the fresh oil). It may be concluded that the oils being used by the informal food processors in Malawi are of poor quality and so the foods cooked in them may be a health hazard to the consumers and the processors themselves. Although this work in ongoing, it may be recommended at the outset that the health department of the city assemblies should inspect these oils for the good health of the consumers. 相似文献
102.
The use of valuation models that focus on lender criteria has been growing in the appraisal field. In the rush to build lender criteria into real estate valuation models, equity investor criteria, expectations, and requirements occasionally have been ignored. The specific criteria considered in this paper are the loan-to-value ratio and the debt coverage ratio for lenders and the equity dividend rate for equity investors. Each of these three criteria may be a binding constraint on value.
Graphical analysis provides a framework within which major real estate valuation models (i.e., Ellwood, McLaughlin, Gettel, Lusht-Zerbst, and Steele) are compared. A new valuation model (i.e., the Cannaday-Colwell model) is developed which utilizes the equity dividend rate.
The three definitional models (i.e., McLaughlin, Gettel, and Steele) are found to be relevant only by mere coincidence. Each of these models simultaneously considers two of the three key criteria, completely eliminating the possibility of consideration of anything else; i.e., the models become tautological.
It is shown that the discounted cash flow based models (i.e., Ellwood, Lusht-Zerbst, and Cannaday-Colwell) each tell one-third of the story. One of these models will be relevant depending upon whether the binding constraint is the maximum loan-to-value ratio, the minimum debt coverage ratio, or the minimum equity dividend rate. The relevant model is the one that yields the lowest value estimate of the three. 相似文献
Graphical analysis provides a framework within which major real estate valuation models (i.e., Ellwood, McLaughlin, Gettel, Lusht-Zerbst, and Steele) are compared. A new valuation model (i.e., the Cannaday-Colwell model) is developed which utilizes the equity dividend rate.
The three definitional models (i.e., McLaughlin, Gettel, and Steele) are found to be relevant only by mere coincidence. Each of these models simultaneously considers two of the three key criteria, completely eliminating the possibility of consideration of anything else; i.e., the models become tautological.
It is shown that the discounted cash flow based models (i.e., Ellwood, Lusht-Zerbst, and Cannaday-Colwell) each tell one-third of the story. One of these models will be relevant depending upon whether the binding constraint is the maximum loan-to-value ratio, the minimum debt coverage ratio, or the minimum equity dividend rate. The relevant model is the one that yields the lowest value estimate of the three. 相似文献
103.
104.
This article assesses Canadian banks' ability to realize scale economies and cost complementarities in joint production. The Canadian banking system, with its 10 or so large banks and 50 smaller ones, offers a good database for a study of efficiency, especially since previous work suggests that the system's concentration has had little impact on system competitiveness. This article estimates a system of cost and cost share equations using Zellner's iterative seemingly unrelated regression technique, then evaluates scale economies and cost complementarities from the estimated cost functions' first and second partial derivatives. The article compares a model that classifies deposits as inputs with another that classifies them as outputs. The empirical findings indicate that deposits are better modelled as outputs than inputs; that Canadian banks organize to exhaust available sources of scale economies and economies in joint production; and that conclusions regarding scale economies and cost complementarities differ importantly according to whether deposits are modelled as inputs or as outputs. 相似文献
105.
106.
107.
108.
This paper analyzes a point in-point out inventory investment under price uncertainty. The optimal quantity is determined by maximizing the expected value of the investor's risk preference function, which is a function of profit. Using an exponential risk preference function, the adjustment in the optimal quantity stemming from a change in the interest rate is investigated. The main conclusion is that the sign of the adjustment depends both on how profit is expressed and on the type of price distribution applied. Contrary to what is assumed in conventional managerial control practices, a rise in the interest rate might lead to an increase in the optimal quantity when present value serves as a measure of profit. 相似文献
109.
110.
Edward H. Kaplan 《Socio》1997,31(4):281-291
We consider a coverage model where an initial event that occurs at some point in time triggers an activity of random duration that leads to some subsequent event. A snapshot sample is constructed at a fixed point in chronological time either by sampling only subjects where the initial event has occurred but the subsequent event has yet to occur (active subjects), or by sampling only subjects where both the initial and subsequent events have occurred (inactive subjects). The biases inherent in snapshot sampling can be neatly characterized by the properties of two random variables: the history
(defined as the time the initial event occurs as measured into the past from the chronological point of sampling), and the active time
(defined as the length of time between the initial and subsequent events). Though snapshot samples are biased, recognizing the biases enables correct inferences to be drawn from snapshot-sampled data. Considering only the case where
and
are independent random variables, this paper presents the probability models associated with snapshot sampling, demonstrates the problems that can occur, offers procedures for overcoming these problems, and applies the methods to interesting data sets. 相似文献