Measuring willingness to pay: do direct methods work for premium durables?

Objective To compare the reproducibility and reliability of facial soft tissue landmarks using a direct and an indirect placement methods in facial three-dimensional (3D) soft tissue assessment.Methods 3D coordinates of 37 soft tissue landmarks were obtained respectively in 35 normal healthy volunteers from 3D optical capture system and Materialise's interactive medical image control system (Mimics).Landmarks were affixed on the cutaneous surface (direct method) and marked on the 3D reconstructed craniofacial model (indirect method).Intra-class correlation coefficients (ICCs) and paired t-tests were used to compare the reliability and reproducibility of facial landmarks between two placement methods.Results For the direct placement method,86.5 ％ landmarks had an ICC higher than 0.75.For the indirect placement method,75.7％ landmarks had an ICC higher than 0.75.The inter-observer variability using the direct placement method was (1.259±0.566) mm,which was significantly smaller (P＜0.05) than (1.420±0.638) mm obtained by the indirect placement method.Conclusions Compared with indirect method,direct method has higher reliability and reproducibility in evaluating facial soft tissue. Key words: Computed tomography; Cephalometrics; Optical capture technology

Analysis of direct and indirect quantification methods of CO2 fixation via microalgae cultivation in photobioreactors: A critical review

Aforestation activities, silvicultural prescription, forest management decisions and land use planning are based on site information to develop appropriate actions for implementation. Forest site classification has been one of the major problems of Turkish forestry for long time. Both direct and indirect methods can be used to determine forest site productivity. Indirect methods are usually reserved for practical applications as they are relatively simple, yet provide less accurate site estimation. However, direct method is highly time-demanding, expensive and hard to conduct, necessitating the use of information technologies such as Geographic Information Systems (GIS) and Remote Sensing (RS). This study, first of all, generated a forest site map using both direct and indirect methods based on ground measurements in 567.2 ha sample area. Then, supervised classification was conducted on Landsat 7 ETM image using forest site map generated from direct method as ground measurements to generate site map. The classification resulted in moist site of 262.5 ha, very moist site of 122.5 ha and highly moist site of 191.2 ha in direct method; sites I-II cover 38.9 ha, III 289.6 ha, IV-V 143.5 ha and treeless-degraded areas of 104.2 ha in indirect method; moist site of 203.5 ha, very moist site of 232.1 ha and highly moist site of 140.6 ha in remote sensing method. However, 104.2 ha treeless and degraded areas were not determined by indirect method, yet by the other methods. Secondly, forest site map for the whole area (5,980.8 ha) was generated based on the site map generated by the direct method for sampled area. The Landsat 7 ETM image was classified based on the forest site map of sample area. The site index (SI) map for the whole area was generated using conventional inventory measurements. The classification resulted in sites I-II cover 134.1 ha, III 1,643.6 ha, IV-V 1,396.5 ha, treeless-degraded areas of 1,097.3 ha and settlement-agriculture areas of 1,709.3 ha in indirect method; moist site of 1,674.3 ha, very moist site of 853.6 ha, highly moist site of 1,729.6 ha and settlement-agriculture areas 1,723.3 ha in remote sensing method. Again the treeless- degraded areas of 1,097.3 ha were not determined by indirect method but by remote sensing method.

Introduction A number of methods of therapy of stuttering have been developed, which can be grouped as direct, indirect and compound methods. Direct methods are aimed at the very speech act and lead to improving speech fluency. Indirect methods are supposed to influence the person and his/her organism. Compound methods are a combination of direct and indirect methods in the form of a therapeutic program. Aim The aim of the overview was to analyze 17 articles that presented studies over the efficiency of direct, indirect and compound therapies of stuttering, as published in PubMed database between 2008 and 2015. Discussion As far as direct methods of stuttering are concerned, devices like SpeechEasy, DAF and FAF (i.e. the one which alter the patient's perception of his/her own speech), as well as a metronome turn out to be really efficient. Indirect methods which use biofeedback, tactile and visual transmission of feedback as well as hypnotherapy combined with diaphragm exercise are equally effective. Laser acupuncture and cognitive therapy seem to improve the positive results achieved by means of other methods. Among the compound methods, Lidcombe Program in its different variants proves to be highly efficient among children, whereas Camperdown Program works well among teenagers and adults. One may have certain hopes with regard to an innovative program referred to as Acceptance and Commitment Therapy. Conclusions Studies on efficiency of therapies of stuttering are scattered, do not cover the whole structure of the disorder and are focused on the symptom i.e. on assessing the severity of speech disfluency. Considering the research done so far, one cannot conclude that some methods are better than others since neither of them were compared in an experimental way.

Affixing markers on the face in vivo with an optical surface imaging system and placing landmarks on a computed tomographic reconstructive facial model represent two helpful approaches prevailing in three-dimensional cephalometric analysis of facial aesthetics. In this study, the authors determine the suitability of these methods for soft-tissue evaluation along with the reproducibility and reliability of landmark placement. Thirty-seven soft-tissue landmarks were investigated in 35 normal healthy volunteers who underwent cephalometric analysis by direct and indirect placement methods. Two operators performed the analysis twice for each method at a 1-week interval. Landmark positions were measured on the three-dimensional coordinates, and data were standardized and converted into landmark placement errors for the estimation, by two-way random intraclass correlation coefficients. Using the direct method, 86.5 percent of the landmarks had a higher intraclass correlation coefficient than 0.75, and 67.6 percent were higher than 0.90. The authors found that 75.7 percent were higher than 0.75 and 43.2 percent were higher than 0.90 with the indirect method. Both methods showed good reliability in identifying midline-related structures, although the correlations of markers surrounding eyelashes and lips were better using the direct method. The direct method had a significantly smaller landmark placement error and better reproducibility than that identified indirectly (p<0.05). When evaluating well-defined contours and the natural texture of the face, the direct placement method shows better accuracy than the indirect method. The three-dimensional evaluation emphasizes the eye, lip, and some structures more laterally, therefore providing comprehensive analysis for clinical diagnosis. Diagnostic, II.

The Direct and Indirect Methods of Ionospheric TEC Predictions and Their Comparison

Forest site classification has long been a problem for managers of Turkish forests. Forest management decisions and land use planning involving afforestation activities and silvicultural prescriptions are based on sound site information to formulate appropriate actions on the ground. In Turkey, two methods of forest site productivity are used; direct and indirect method. Indirect methods are usually reserved for practical applications as they are relatively simple, yet provide less accurate estimation of the real productivity. In this study direct, indirect and remote sensing (RS) methods were used to distinguish and map forest sites of Karanlikdere Forest District in Gumushane, Turkey. One hundred and twenty-two sample plots were established with 300 m × 300 m grids in summer of 2003. In each sample plot, soil samples and the classical timber inventory measurements were taken. According to direct method, water-air economy method is preferred due to a water deficiency in the study area. Four different forest site classes; very dry, dry, moderate fresh and fresh were determined and mapped with geographic information system (GIS). In indirect method, the guiding curve was used to generate anamorphic site indexes (SI) of three classes; good (SI = I and II), medium (SI = III) and poor (SI = IV and V). Furthermore, forest sites were estimated with Landsat 7 ETM (2000) data using supervised classification with a 0.843 kappa statistic value and 88% accuracy assessments. Some important differences between the methods were discovered. The indirect method indicate that site indices I and II are 298.5 ha, III 254.3 ha and IV and V 347.7 ha. In contrast, direct method related to very dry site of 107.7 ha, dry site of 484.6 ha, moderate fresh site of 304.7 ha and fresh site of 246.3 ha. Satellite image indicate that very dry site covers 291.2 ha, dry site 239.2 ha, moderate fresh site 287.4 and fresh site 325.5 ha. Approximately 242.8 ha area (open and degraded areas) were not determined by indirect method but were captured with RS method. The statistical analyses (ANOVA) showed no statistically significant (F = 0.720, p = 0.543) relationship between indirect method and direct method-RS method indicating clearly that indirect method is not an adequate measurement of forest site productivity. Forest sites, particularly in open and degraded areas should be determined with direct method.

This paper gives a brief list of commonly used direct and indirect efficient methods for the numerical solution of optimal control problems. To improve the low accuracy of the direct methods and to increase the convergence areas of the indirect methods we suggest a hybrid approach. For this a special direct collocation method is presented. In a hybrid approach this direct method can be used in combination with multiple shooting. Numerical examples illustrate the direct method and the hybrid approach.

The paper aims to investigate the impact of presenting statements of cash flow using the direct method and the indirect method on loan decision by credit officers at Vietnamese banks. The data was collected from 150 credit officers of commercial banks in Vietnam based on the questionnaire about making loan decision when the cash flow statement is presented in different methods, namely, direct and indirect methods. This research uses T-tests to check whether using the direct or indirect method affects the accurate calculation of loan criteria, affects the loan decision by credit officers, and compare these two methods in the aspects of information provision. The research has pointed out that: 1) the direct method helps the calculation of indicators related to loans more accurately; 2) credit officers say that, while the direct method of presenting cash flow statement provides clearer information, the use of either the direct method or the indirect method does not affect the banks' loan decision. Since then, the author recommends that cash flow statements should be provided with information in a direct method to present the information needed for loan decision more accurately so as to improve the quality of cash flow statement.

Direct or indirect methods can be used to determine the DE and ME of feed ingredients for pigs. In situations when only the indirect approach is suitable, the regression method presents a robust indirect approach. Three experiments were conducted to compare the direct and regression methods for determining the DE and ME values of barley, sorghum, and wheat for pigs. In each experiment, 24 barrows with an average initial BW of 31, 32, and 33 kg were assigned to 4 diets in a randomized complete block design. The 4 diets consisted of 969 g barley, sorghum, or wheat/kg plus minerals and vitamins for the direct method; a corn-soybean meal reference diet (RD); the RD + 300 g barley, sorghum, or wheat/kg; and the RD + 600 g barley, sorghum, or wheat/kg. The 3 corn-soybean meal diets were used for the regression method. Each diet was fed to 6 barrows in individual metabolism crates for a 5-d acclimation followed by a 5-d period of total but separate collection of feces and urine in each experiment. Graded substitution of barley or wheat, but not sorghum, into the RD linearly reduced ( < 0.05) dietary DE and ME. The direct method-derived DE and ME for barley were 3,669 and 3,593 kcal/kg DM, respectively. The regressions of barley contribution to DE and ME in kilocalories against the quantity of barley DMI in kilograms generated 3,746 kcal DE/kg DM and 3,647 kcal ME/kg DM. The DE and ME for sorghum by the direct method were 4,097 and 4,042 kcal/kg DM, respectively; the corresponding regression-derived estimates were 4,145 and 4,066 kcal/kg DM. Using the direct method, energy values for wheat were 3,953 kcal DE/kg DM and 3,889 kcal ME/kg DM. The regressions of wheat contribution to DE and ME in kilocalories against the quantity of wheat DMI in kilograms generated 3,960 kcal DE/kg DM and 3,874 kcal ME/kg DM. The DE and ME of barley using the direct method were not different (0.3 < < 0.4) from those obtained using the regression method (3,669 vs. 3,746 and 3,593 vs. 3,647 kcal/kg DM, respectively). The direct method-derived DE and ME of sorghum were not different (0.5 < < 0.7) from those obtained using the regression method (4,097 vs. 4,145 and 4,042 vs. 4,066 kcal/kg DM, respectively). The direct method- and regression method-derived DE (3,953 and 3,960 kcal/kg DM, respectively) and ME (3,889 and 3,874 kcal/kg DM, respectively) of wheat were not different (0.8 < < 0.9). Results of these 3 experiments suggest that regression and direct methods do not give different estimates of DE and ME in barley, sorghum, and wheat for pigs.

Conservation agriculture (CA) is an agronomic system, including no‐tillage, cover crops and residue retention on the soil surface, which represents more sustainable management compared to conventional ploughing systems (CV). Conservation agriculture is widespread in some parts of the world (i.e. South America and the USA), whereas it is still developing in others (i.e. Europe). One of the main reasons for the slow European uptake of CA is low yield because of the worsening of soil physical quality, in particular increased compaction and reduced hydraulic permeability. The effects of CA on soil physical dynamics are poorly documented, particularly during the transition phase between CV and CA and for fine‐textured soils. Therefore, in this study, the effects of CA on soil volumetric water content, bulk density, penetration resistance and electrical resistivity are presented over a 3‐year monitoring period. The experiment was established in 2010 on four farms in the Veneto region (northeastern Italy) with silty soils, where CA practice was compared with CV. The dynamics of soil physical properties were monitored from 2014 to 2016 following a 3‐year crop rotation cycle. Every year, bulk density analysis, a penetration resistance test and three‐dimensional electrical resistivity tomography were performed. The results showed that soil physical properties clustered depending on soil texture: in silty loam soils any specific improvements were highlighted after 6 years of CA, whereas in loamy soils soil compaction was observed in both CA and CV. Indeed, CA resulted in soil compaction below a depth of 10 cm (+107% of degree of compaction), whereas CV resulted in the formation of a plough pan in the 35–55‐cm layer (+111% of degree of compaction). The low soil organic carbon and low clay contents made loamy soil particularly prone to compaction, highlighting the influence of fine texture on soil structure evolution during the transition phase. Highlights Greater organic matter content and biological activity might offset compaction in CA during transition phase CA did not suffer from soil compaction on silty soil while ERT detected a plough pan in loamy soil under CV Geophysics integrated with direct assessment methods is a useful tool for studying soil structure evolution No specific benefits or drawbacks were highlighted after 6 years of CA adoption with respect to CV in silty soil

We combine results from interferometry, asteroseismology and spectroscopy to determine accurate fundamental parameters of 23 bright solar-type stars, from spectral type F5 to K2 and luminosity classes III–V. For some stars we can use direct techniques to determine the mass, radius, luminosity and effective temperature, and we compare with indirect methods that rely on photometric calibrations or spectroscopic analyses. We use the asteroseismic information available in the literature to infer an indirect mass with an accuracy of 4–15 per cent. From indirect methods we determine luminosity and radius to 3 per cent. We find evidence that the luminosity from the indirect method is slightly overestimated (&amp;ap; 5 per cent) for the coolest stars, indicating that their bolometric corrections (BCs) are too negative. For &lt;it&gt;T&lt;/it&gt;&lt;inf&gt;eff&lt;/inf&gt; we find a slight offset of −40 ± 20 K between the spectroscopic method and the direct method, meaning the spectroscopic temperatures are too high. From the spectroscopic analysis we determine the detailed chemical composition for 13 elements, including Li, C and O. The metallicity ranges from [Fe/H]=−1.7 to +0.4, and there is clear evidence for α-element enhancement in the metal-poor stars. We find no significant offset between the spectroscopic surface gravity and the value from combining asteroseismology with radius estimates. From the spectroscopy we also determine &lt;it&gt;v&lt;/it&gt; sin &lt;it&gt;i&lt;/it&gt; and we present a new calibration of macroturbulence and microturbulence. From the comparison between the results from the direct and spectroscopic methods we claim that we can determine &lt;it&gt;T&lt;/it&gt;&lt;inf&gt;eff&lt;/inf&gt;, log &lt;it&gt;g&lt;/it&gt; and [Fe/H] with absolute accuracies of 80 K, 0.08 and 0.07 dex. Photometric calibrations of Strömgren indices provide accurate results for &lt;it&gt;T&lt;/it&gt;&lt;inf&gt;eff&lt;/inf&gt; and [Fe/H] but will be more uncertain for distant stars when interstellar reddening becomes important. The indirect methods are important to obtain reliable estimates of the fundamental parameters of relatively faint stars when interferometry cannot be used. This paper is the first to compare direct and indirect methods for a large sample of stars, and we conclude that indirect methods are valid, although slight corrections may be needed.

Low adherence of patients to antihypertensive therapy remains an urgent problem and is recognized as the main cause of insufficient BP control at the population level. In this regard, to increase the motivation of patients in clinical practice, methods for assessing adherence (compliance) to drugs. Along with indirect assessment methods (questionnaires, self-reports, pill counts, etc.), which, however, do not always reflect the real patients adherence, more objective is the measurement of antihypertensive drug concentrations in physiological fluids therapeutic drug monitoring (TDM). For these purposes, methods of high-performance liquid chromatography with mass spectrometry were recently adapted, reference ranges of antihypertensive drug concentrations in blood serum and urine for standard doses of drugs were determined, as well as criteria for assessing complete or partial non-compliance. There have been a number of studies using TDM to assess adherence, which show a high rate of non-compliance (low compliance) of more than 50% of cases with a variability from 25 to 86.1%, with complete non-compliance 10.134.5% in patients with uncontrolled and/or resistant hypertension (3 antihypertensive drug). In a population of patients with a normal course of hypertension, taking 12 antihypertensive drug, the level of non-compliance according to the results of TDM did not exceed 10%. Comparison of the TDM method with indirect methods of assessing adherence did not reveal consistency; at the same time, the detection of antihypertensive drug better characterized the clinical problems of patients with arterial hypertension. In clinical practice, direct assessment methods (TDM) can be used to measure adherence in problem patients with uncontrolled hypertension and high cardiovascular risk despite optimal therapy.

Age estimation from primary teeth is an important matter for forensic odontology, which can be found by the application of direct or indirect age estimation methods that are functions of tooth measurements. The most distinctive teeth among these are the upper central incisors, because of their early development. The aim of this study is to determine the age of fetuses or infants by measuring the tooth development directly from tooth surfaces or from indirect measurements obtained from the tooth structures on the computerized tomography digital images. The data of all measurements were statistically processed by regression analysis and regression formulas were derived. The results revealed that age could be estimated from various tooth dimensions within an accuracy of ±0-2 weeks for both methods and therefore indirect method -which was proposed as Virtual Dental Identification (VirDent-ID) by the authors PS. Aka and N. Canturk- could be a matter of choice instead of traditional direct oral autopsy methods. The best measurements for age estimation can be obtained from the longest vertical dimension, which is the tooth height, and the best age estimation formula was also generated from the tooth height. In conclusion, age formulas derived from direct or indirect measurements of fetus or infant tooth development stages may be used as an aid for dental identification, until the completion of upper central primary tooth development.

The as-cast properties of components with a columnar grain structure are very different from those with an equiaxed one. Under certain solidification conditions, zones of both structures can occur in an alloy casting; the boundary between the zones is the columnar-to-equiaxed transition (CET). A front-tracking model of dendritic solidification has been developed, which can predict the nucleation and growth of solid in undercooled liquid during a casting process. The growth process is described by dendrite tip kinetics, and is fully coupled to a fixed-grid control volume model of heat transfer during solidification. Using the front-tracking model, two methods for predicting the likelihood of an equiaxed zone forming ahead of a columnar front have been formulated, namely, an indirect method and a direct method. The indirect method is based on modelling the growth of the columnar front in the absence of equiaxed nucleation. The bulk liquid undercooling is monitored and an equiaxed indicator is calculated at each time step based on the extent of such undercooling at that time. The equiaxed indicator is a measure of the relative likelihood of an equiaxed zone forming. In the direct method nucleation and growth of individual equiaxed grains is treated ahead of the advancing columnar front. In this case, if impingement of neighbouring fronts is treated, the simulation to complete solidification will yield the macrostructure and the CET. In this paper, details of both methods of equiaxed prediction are presented. Results from the indirect method are compared to experimental results found in literature and agreement is found.