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This research is associated with the real-time parameters of wide- and narrow-body aircraft to recognize the quantitative relationship framework. This paper aims to find the superiority of aircraft design technology which triggers the reduction in specific fuel consumption (SFC) and economic competitiveness.

The real case study is performed with 22 middle-of-the-market (MoM) aircraft. This paper develops a fuel burn mathematical model for mid-size transport aircraft by a multi-linear regression approach. In addition, sensitivity analysis is performed to establish the authentication of the fuel burn model.

The study reveals that the MoM aircraft would be the future aircraft design in terms of better fuel economy and carbon footprint. From the multi-regression analysis, it is observed that the logarithmic regression model is the best fit for estimating the SFC. Moreover, fineness ratio, aspect ratio, gross weight, payload weight fraction, empty weight fraction), fuel weight fraction, payload, wing loading, thrust loading, range, take-off distance, cruise speed and rate of climb are observed as the suitable parameters which provide the best fitness value as 0.9804.

Several existing literature reveals that a few research has been performed on the MoM aircraft with wide-body configuration. Moreover, mathematical modelling on the fuel consumption was insignificantly found. This study examines several parameters which affect the fuel consumption of a wide-body aircraft. A real-case study for design configurations, propulsive systems, performance characteristics and structural integrity parameters of 22 different MoM aircraft are performed. Moreover, multi-regression modelling is developed to establish the relation between SFC and other critical parameters.

The decision maker is in charge of procurement auctions at the department of transportation of Orangia (a fictitious U.S. state). Students are asked to assist him in estimating the winning bids in various auctions concerning highway repair jobs using data on past auctions. The decision maker is faced with various professional, statistical, and ethical dilemmas.

To analyze highway procurement auctions from the buyer-auctioneer perspective, establish basic facts regarding the project price-to-estimated cost ratio, set up and estimate a structural regression model to predict the winning bid, and compute the probability the winning price will be below estimated cost. Difficulties include heteroskedasticity, logarithmic specification, and omitted variable bias. Also to estimate a Logit regression and predict bidder collusion probability.

The purpose of this paper is to compare light fastness assessments by exposure of fabric dyes with various dyes in daylight and an artificial xenon arc lamp.

Cotton fabric dyed with 66 reactive, vat, azoic and direct dyes dyed in different depths were exposed to daylight and Xenon arc lamp for assessment of light fastness by standard methods. The light fastness rating and fading hours by the two methods were analysed and compared statistically.

The correlation between the corresponding light fastness rating (LFR) measured in Xenotest and daylight is quite high (0.93). The logarithmic correlation coefficients between fading hour (FH) and LFR in Xenotest and daylight are 0.95 and 0.88, respectively. For Xenotest, the assessed LFRs are same as those predicted from geometric progression up to LFR of 5.5, and thereafter, the former is higher. On the other hand, in the case of daylight, the assessed LFR is lower. Assessments for three successive seasons showed high repeatability in case of Xenotest and moderate repeatability in case of daylight. Assessments for three successive seasons showed high repeatability in case of Xenotest and moderate repeatability in case of daylight.

The exposure conditions in daylight cannot be controlled or standardised, whereas the exposure in Xenon arc lamp in the accelerated fading instrument can be strictly controlled. These differences in exposure control may affect the repeatability of experimental findings.

Inconsistent ratings may be because of little deterioration of samples during storage, as well as seasonal variation of daylight.

There are no direct social implications.

The researches on the comparison of the two light fastness assessment methods have not been reported in any recent publication to the best our knowledge.

Sago starch (Metroxylon sagu Rottb.) is one of the starches imported into Japan. Recently, sago starch has been promoted as a healthy type of starch because it is gluten-free and non-allergenic. This study aims to identify the factors affecting sago starch import demand during the period 1978–2017 in Japan by using a double logarithmic linear function. The study revealed that the price of sago starch, GDP, aging population rate and tariff-rate quota policy are significant factors influencing sago starch importation in Japan.

Time is an important factor in any project, especially in construction projects. Although using detailed scheduling techniques is unavoidable, a model to predict or benchmark time performance has interested many researchers. For an exploratory purpose, this paper aims to investigate the time‐cost relationship proposed by Bromilow with data from construction projects in Korea.

The data are collected from 34 historical building projects in Korea. Construction cost is adjusted using a building price index. Analysis is carried out on variety of project characteristics.

It is shown that a time‐cost relationship is applicable to the Korean construction industry. Further analysis indicates that the original Bromilow time‐cost model is not the best fit regression form, and alternative models are proposed.

The data are limited to a small sample of 34 building projects. This limitation arises because of the data collection approach, which is direct contact with historical project documents supplied by construction firms.

Models from this study can serve as a reference tool for practitioners in the early stages of building projects in Korea. The results from this study are not intended to reject or replace detailed construction scheduling techniques.

The purpose of this paper is to investigate the relationship between the number of design elements in the context of building facades in urban streetscapes and visual preferences of users to enable a more meaningful citizen participation in the design of local streetscapes.

This paper developed a web application, which manages experiments through programmatically creating scenes and displaying them online to participants using questionnaires. It collects preferences towards the number of design elements in the scenes and determines the statistical relationship between them.

The results offer an empirical description of a semi-convex relationship between the number of elements and preferences. They confirm that participants from a particular area inter-subjectively agree in their visual judgements towards the number of design elements, and justify the employment of a regression model fitted on the preferences of residents to assess design proposal in their area.

The paper offers an empirical description of the relationships between preferences and a wide range of values of the number of design elements and empirically supports that people from one area inter-subjectively agree in their judgements towards a visual aspect of the building facades. The study introduces a new analytical component, known as the vertex, which could alter future methods on the visual evaluation of the built environment.

Supplements the (A) case.

Based on the GARCH model, the divorce rate in Taiwan is found to be negatively affected by the fertility rate and male earnings and positively influenced by the male unemployment rate, female earnings, female education, and institutional changes providing married women more protection in child custody, child support and alimony and property rights in divorce. The conventional OLS regression method yields poor statistical outcomes.

This study aims to explore the effect of mass media exposure on women contraceptive adoption. The intent was to show how factors affected contraceptive use, such as education, standards of living, etc., behave differently across the poverty line.

Logistic regression was used to test the effect of exposure of various mass media on contraceptive adoption. Indian Human Development Survey (2005) was used for the analysis. Analysis was performed to compare results across the poverty line.

Television exposure was found to be significant, and it had a strong effect on the likelihood that the family uses contraceptives. Newspaper readership was found significant above the poverty line and insignificant below.

The present study only analyzes cross-sectional data. A longitudinal study would be better suited to determine how these factors affect contraceptive use over time.

The findings of this study can be useful in designing more effective media mix for the communications aimed at increasing contraceptive use in India.

The findings show the divide between the population segments above and below the poverty line. Low education levels, affordability issues and son preferences are the major factors deterring contraceptive use at this level.

This is the first study to separately study the population samples across the poverty line. Compared to previous studies which focuses heavily on one media, this analysis includes other media variables and focuses on a variation of these factors across the poverty line.

The purpose of this paper is to extract the location attributes, which are the most important for market value of real estate in countries with well‐developed markets.

In this paper meta‐analysis is applied for extraction of location attributes and the weights of their importance. The outcomes of existing regression models created in different countries mainly with a developed real estate market are used. A total of 81 models described in 39 sources are analysed.

The paper finds that the lists of statistically significant location attributes, which influence market value, are obtained for different real estate types. The weights of attributes' relative influence are compared, where possible.

In the paper meta‐analysis is also applied for a limited number of empirical studies. However, for land and residential real estate the number of sources is sufficient to make a substantiated conclusion. The application of the outlined location attributes is a subject for future research.

The paper shows that the lists of important location attributes can be used for practical specification of the valuation models for urban land and other real estate in countries where the market is underdeveloped, to increase the degree of objectivity and market orientation.

The paper is one of the few studies which synthesize the findings of existing regression models with respect to location attributes generally. The method of weights' estimation is original. The result of the paper has practical value for real estate valuation in countries with an underdeveloped market.