Lag Criterion Research Articles

AGRICULTURAL FINANCE AND ECONOMIC GROWTH: EVIDENCE FROM NIGERIA

The study performed an in-depth examination of the impact of guaranteed agricultural finance to oil palm, cocoa, groundnuts, fishery, poultry, cattle, roots, and tubers on the real gross domestic product of the country. Time series data was sourced from the Central Bank of Nigeria statistical bulletin of various issues. The data sets covered thirty-seven (37) years spanning from 1981 to 2017. The study used Autoregressive Distributed Lag (ARDL) model for its analysis. However, prior estimation and due to several exogenous variables, Phillip Perron stationarity test was used to determine the order of integration because of its robustness to serial correlation and heteroskedasticity. The study also specified the lag criterion based on LR, FPE, AIC, SC, and HQ using Newey-West covariance matrix estimator. Findings from both short-run and long-run models as confirmed by the Wald test, which shows that none of the guaranteed agricultural finance is statistically significant to real gross domestic product. The study, therefore, recommends increased funding and deliberate efforts at determining which of the nominated agricultural spending has the most contributory impact on growth.

An evaluation of lag schedules and prompting methods to increase variability of naming category items in children with autism spectrum disorder.

A lag schedule of reinforcement is one way to increase response variability; however, previous research has been mixed with regard to the necessary parameters to increase variability. For some individuals, low schedule requirements (e.g., Lag 1) are sufficient to increase variability. For other individuals, higher lag schedules (e.g., Lag 3) or a lag schedule in combination with prompting is needed to increase variability. We evaluated the efficiency of different within-session progressive lag schedules to increase response variability with 2 children with autism. Results showed that increasing the lag criterion across sessions increased variability to levels similar to beginning with a high lag schedule for one participant. When lag schedules did not increase variability for the second participant, we compared a variety of prompting procedures. Results of the prompting evaluation showed that a tact-priming procedure was effective to increase varied responding.

Investigation the Arithmetical or Tabular Islamic calendar

Arithmetical calendar (or tabular calendar) is sometimes referred to as the Fātimid calendar but this is in fact one of several almost identical tabular Islamic calendars. This calendar introduced by Muslim astronomers in the 9th century CE to predict the approximate begin of the months in the Islamic lunar calendar. Chronologists adopted 11 leap years in a 30 year cycle. In the case of leap Hijri year they add one day to the last month of the Hijri year. The cycle of this calendar agree with the Smaller cycles (2–5.333 years) discovered by Galal and Rashed (2011) and coincide with the lag criterion given by Galal (1988).We suggested the Islamic tabular calendar. The Leap years of this suggested Islamic tabular calendar may be 2, 5, 7, 10, 13, 15, 18, 21, 23, 26 and 29. Our suggested Arithmetical calendar satisfies the mathematical patterns, while the old Arithmetical calendar (or tabular calendar) does not satisfy a known fixed rule.We conclude empirical formula for our suggested Islamic tabular calendar. From this empirical formula, we can calculate if the Hijric year after immigration is a leap or a non-leap year.

Exploring the potential linkages between oil‐field brine reinjection, crystalline basement permeability, and triggered seismicity for the Dagger Draw Oil field, southeastern New Mexico, USA, using hydrologic modeling

AbstractWe used hydrologic models to explore the potential linkages between oil‐field brine reinjection and increases in earthquake frequency (up to Md 3.26) in southeastern New Mexico and to assess different injection management scenarios aimed at reducing the risk of triggered seismicity. Our analysis focuses on saline water reinjection into the basal Ellenburger Group beneath the Dagger Draw Oil field, Permian Basin. Increased seismic frequency (>Md 2) began in 2001, 5 years after peak injection, at an average depth of 11 km within the basement 15 km to the west of the reinjection wells. We considered several scenarios including assigning an effective or bulk permeability value to the crystalline basement, including a conductive fault zone surrounded by tighter crystalline basement rocks, and allowing permeability to decay with depth. We initially adopted a 7 m (0.07 MPa) head increase as the threshold for triggered seismicity. Only two scenarios produced excess heads of 7m five years after peak injection. In the first, a hydraulic diffusivity of 0.1 m2 s−1 was assigned to the crystalline basement. In the second, a hydraulic diffusivity of 0.3 m2 s−1 was assigned to a conductive fault zone. If we had considered a wider range of threshold excess heads to be between 1 and 60 m, then the range of acceptable hydraulic diffusivities would have increased (between 0.1–0.01 m2 s−1 and 1–0.1 m2 s−1 for the bulk and fault zone scenarios, respectively). A permeability–depth decay model would have also satisfied the 5‐year time lag criterion. We also tested several injection management scenarios including redistributing injection volumes between various wells and lowering the total volume of injected fluids. Scenarios that reduced computed excess heads by over 50% within the crystalline basement resulted from reducing the total volume of reinjected fluids by a factor of 2 or more.

Energy Consumption, Electricity, and GDP Causality; The Case of Russia, 1990-2011

Abstract This article examines the causal relationship between the energy consumption, electricity consumption and GDP in Russia by using time series data from 1990-2011 implying the Toda and Yamamoto approach, which is revised form of the Granger (1969) causality test (Econ. 66 (1995) 225). The maximum order of integration was determined by using PP and ADF unit root tests. The Toda and Yamamoto test is applied regardless of whether the series are I(0), I(1), or I(2), mutually cointegrated or non-cointegrated. The variables were estimated at level in the unrestricted lag-augmented VAR. The AIC, SC and LR lag criteria were used to determine the optimal lag length. The diagnostics tests were performed at the optimum lag selected by estimating the variables at level and confirmed the stability of the unrestricted VAR model. The empirical evidence showed that there exists a the bi-directional causality from electricity consumption to GDP that implies the validity of feedback hypothesis but no causality was found for GDP and energy consumption supporting the neutrality hypothesis. The estimated results confirmed that both the economic growth and electricity consumption empirically support each other and have a mutual and complementary relationship. But on another hand the energy sector of Russia has no impact on the economic growth for a period 1990-2011. Furthermore, if the Government of Russia devises policies to promote the access of energy and higher level of consumption, economic growth will not be affected.

Increasing response variability in children with autism spectrum disorder using lag schedules of reinforcement

Individuals with autism spectrum disorder (ASD) often present with deficits in variability in responding across multiple repertoires. However, research to date has resulted in little empirical evaluation of remediation strategies for such deficits. We investigated the effects of lag schedules of reinforcement on response variability using a computer-based task designed for the purpose of the study. The U-value statistic was used as a measure of variability in responding to determine if increasing the lag criterion would correspondingly increase levels of variability. Participants included children with ASD (Group 1) and neurotypical children (Group 2). Results showed that U-values were higher when reinforcement was contingent on increased variability, indicating the effectiveness of higher lag values on response variability. A significant difference in response variability between groups provided evidence for the disparity in such responding in children with ASD compared to their neurotypical peers. Group 1 showed consistently lower U-values than Group 2 indicating lower response variability. However, data from this study clearly show that lag schedules of reinforcement may be employed to increase response variability in ASD.

Dynamic Relationship Between Gross Domestic Product and Domestic Investments in Rwanda

This study uses a VAR model to analyse the dynamic relationship between gross domestic product (GDP) and domestic investment (DI) in Rwanda for the period 1970 to 2011. Several selection lag criteria chose a maximum lag of one and a bivariate VAR(1) model specification in levels was adopted. Unit root tests show that both GDP and DI series are nonstationary in levels but stationary in first differences, implying that both are integrated of order one I(1). Tests of cointegration established that GDP and DI are CI(1,1), suggesting there is a long-run equilibrium relationship between the two series. The error correction model indicates that DI adjusts to GDP with a lag whereby 0.2 percent of the discrepancy between long-term and short-term DI is corrected within the year. Granger causality tests show that there is unidirectional causality where GDP causes DI. The bivariate VAR (1) was unstable when estimated at levels, but was stable in first differences. Finally it was found out that GDP almost perfectly predicts DI in the estimated VAR (1) model. The forecasted value of DI in 2011 was 22.6%of GDP while the actual value was 22.7% of GDP. The small discrepancy may be attributed to the appropriate policy measures the Rwandan government and the private sector federation have thus far taken to facilitate investors in their businesses. Keywords : Gross Domestic Product (GDP); Domestic Investment (DI); Granger Causality; Cointegration; Vector Autoregression (VAR) and Vector Error Correction Model (VECM)

Dynamic Relationship Between Gross Domestic Product and Domestic Investments in Rwanda

This study uses a VAR model to analyse the dynamic relationship between gross domestic product (GDP) and domestic investment (DI) in Rwanda for the period 1970 to 2011. Several selection lag criteria chose a maximum lag of one and a bivariate VAR(1) model specification in levels was adopted. Unit root tests show that both GDP and DI series are nonstationary in levels but stationary in first differences, implying that both are integrated of order one I(1). Tests of cointegration established that GDP and DI are CI(1,1), suggesting there is a long-run equilibrium relationship between the two series. The error correction model indicates that DI adjusts to GDP with a lag whereby 0.2 percent of the discrepancy between long-term and short-term DI is corrected within the year. Granger causality tests show that there is unidirectional causality where GDP causes DI. The bivariate VAR (1) was unstable when estimated at levels, but was stable in first differences. Finally it was found out that GDP almost perfectly predicts DI in the estimated VAR (1) model. The forecasted value of DI in 2011 was 22.6% of GDP while the actual value was 22.7% of GDP. The small discrepancy may be attributed to the appropriate policy measures the Rwandan government and the private sector federation have thus far taken to facilitate investors in their businesses.

Dynamic Relationship between Gross Domestic Product and Domestic Investment in Rwanda

This study uses a VAR model to analyse the dynamic relationship between gross domestic product (GDP) and domestic investment (DI) in Rwanda for the period 1970 to 2011. Several selection lag criteria chose a maximum lag of one, and a bivariate VAR(1) model specification in levels was adopted. Unit root tests show that both GDP and DI series are nonstationary in levels but stationary in first differences, implying that both are integrated of order one I(1). Tests of cointegration established that GDP and DI are CI(1,1), suggesting there is a long-run equilibrium relationship between the two series. The error correction model indicates that DI adjusts to GDP with a lag whereby 0.2 percent of the discrepancy between long-term and short-term DI is corrected within the year. Granger causality tests show that there is unidirectional causality where GDP causes DI. The bivariate VAR (1) was unstable when estimated at levels, but was stable in first differences. Finally it was found out that GDP almost perfectly predicts DI in the estimated VAR (1) model. The forecasted value of DI in 2011 was 22.6% of GDP while the actual value was 22.7% of GDP. The small discrepancy may be attributed to the appropriate policy measures the Rwandan government and the private sector federation have thus far taken to facilitate investors in their businesses.

Using a lag schedule to increase variability of verbal responding in an individual with autism.

Research has shown that reinforcing novel behaviors can increase the number of different ways that an individual behaves (Goetz & Baer, 1973; Pryor, Haag, & O'Reilly, 1969). However, it was not until more recently that researchers began to consider variability to be a reinforceable operant in and of itself (Neuringer, 2002). More specifically, Neuringer suggested that variability can be taught using a Lag x schedule of reinforcement, in which x refers to the number of previous responses from which the current response must differ in order for reinforcement to occur (Page & Neuringer, 1985). The purpose of the present study was to extend one of the first studies of a Lag x schedule on verbal responses with human subjects (Lee, McComas, & Jawor, 2002), by increasing the lag criteria while attempting to address some of methodological limitations of the study. The participant was a 7-year-old male with autism. A changing criterion design was used and results showed that 3 novel responses were acquired and varied according to the lag schedule of reinforcement.

The Accommodative Lag of the Young Hyperopic Patient

To determine the accommodative accuracy of infants and young children before they had had any form of clinical intervention or treatment, in an attempt to determine the difference between 'normal' and 'abnormal' visual experience for these individuals. Nott retinoscopy was performed on 111 subjects in binocular viewing conditions at a viewing distance of 50 cm. The target was a naturalistic cartoon image with a broadband spatial frequency amplitude spectrum. Accommodative accuracy was not related to age (4-90 months). In the group found to have no apparent clinical abnormality (n = 71), the mean lag in the more hyperopic meridian of the least ametropic eye was 0.34 diopters (D). When considering the group as a whole, those with less than approximately 4 D of hyperopia demonstrated similar lags, while those with higher hyperopia, amblyopia, or strabismus had more variable lags. An ROC analysis designed to detect hyperopia >5 D in any meridian, amblyopia and/or strabismus had an area under the curve of 0.90 (95% confidence interval [CI], 0.82 to 0.95), and for a lag criterion of 1.3 D had a sensitivity of 83.3% and a specificity of 96.5%. These data from a relatively small but broad sampling of age and clinical status suggest that clinically normal young infants and children with low amounts of hyperopia have similar lags of accommodation from the first few months after birth. Subjects with greater than 4 D of hyperopia, or amblyopia or strabismus, have more variable lags and therefore evidence of abnormal visual experience.

Export linkage to economic growth: evidence from Iran

PurposeThe purpose of this paper is to test the export‐led growth hypothesis for Iran.Design/methodology/approachThis is done through an investigation of causal relationship between exports and economic growth, based on Hsiao's synthesis and Akaike's optimal lag criterion, and then by examining the impact of disaggregated exports on economic growth. Using annual time series data, it covers the period of 1970‐2001.FindingsThe evidence supports the export‐led growth hypothesis for aggregate exports. This is not due to accounting effect; since the results indicate that real export growth also causes net‐real GDP growth for Iran. In examining the effects of decomposition of exports and growth, while oil exports are found to have a very important role, manufactured exports are suggested to have the potential to bear further growth in the future.Originality/valueThe paper provides evidence from Iran linking exports to economic growth.

Hydrogen permeation in gamma titanium aluminides

The permeation of hydrogen in gamma titanium aluminides was studied using the Devanathan–Stachurski (DS) cell. Thin disk-shaped samples of gamma titanium aluminide with three different microstructures were appropriately prepared and cathodically charged in an aqueous 0.1 N NaOH solution. The permeation current was monitored as a function of time. Permeation parameters were calculated using the time lag criterion (non-steady state lag). Values of the apparent diffusion coefficient of hydrogen in gamma titanium aluminide varying from 1.87 × 10 −7 cm 2/s to 3.75 × 10 −6 cm 2/s were obtained. This slight variation is attributed to differences in microstructure.

Variation, repetition, and choice.

Experiment 1 investigated the controlling properties of variability contingencies on choice between repeated and variable responding. Pigeons were exposed to concurrent-chains schedules with two alternatives. In the REPEAT alternative, reinforcers in the terminal link depended on a single sequence of four responses. In the VARY alternative, a response sequence in the terminal link was reinforced only if it differed from the n previous sequences (lag criterion). The REPEAT contingency generated low, constant levels of sequence variation whereas the VARY contingency produced levels of sequence variation that increased with the lag criterion. Preference for the REPEAT alternative tended to increase directly with the degree of variation required for reinforcement. Experiment 2 examined the potential confounding effects in Experiment 1 of immediacy of reinforcement by yoking the interreinforcer intervals in the REPEAT alternative to those in the VARY alternative. Again, preference for REPEAT was a function of the lag criterion. Choice between varying and repeating behavior is discussed with respect to obtained behavioral variability, probability of reinforcement, delay of reinforcement, and switching within a sequence.

Exports, growth and causality in LDCs: A re-examination

Using Akaike's optimal lag criterion in a Granger causality test, the causal relationship between export growth and economic growth (and vice versa) is re-examined for 20 countries. It is argued that earlier analyses which ignore optimal lags in Granger or Sims causality tests suffer from certain shortcomings which are overcome by the present approach. The results suggest some support for the export promotion hypothesis, especially in the case of well-known NICs and thus differ from previous applications of Granger test which did not adopt an optimum lag criterion, and which showed no causality from export growth to economic growth in such cases. However, they are inconclusive in evaluating competing hypotheses.

Cross-correlation and latency compensation analysis of click-evoked and frequency-following brain-stem responses in man

Cross-correlation (CC) and latency compensation (LC) analyses were applied to the human click-evoked brain-stem auditory evoked response (BAER) and the brain-stem frequency-following response (FFR). FFRs were elicited by pure tone stimuli (230 Hz and 460 Hz) or by complex tones derived from the sum of 3rd (920 Hz), 4th (1150 Hz), and 5th (1380 Hz) harmonics of the missing 230 Hz fundamental. The lower and upper harmonics always began in sine phase, while the middle harmonic varied in starting phase, resulting in harmonically complex stimuli with differing amplitude and phase patterns. Cross-correlations were computed between individual trials and a wave form t emplate (smoothed wave V for BAER, pure tone stimulus sinusoids for FFR). Trials were included in the analysis only if values of r 2 exceeded 0.5 (negative values of r were thus included, which controlled for the chance occurrence of positive correlations). Although brain-stem recordings are noisy, requiring as many as 1000 stimuli/average, correlation analysis consistently identified more positive than negative trials (approximately 2:1 ratio). Trials were also deleted if the lag associated with the selected r 2 was at the maximum shift position (‘extreme lag’). Averaging trials that satisfied the correlation and lag criteria led to sizeable enhancement of BAER (mean = 114%) and FFR (mean = 68% for 230 Hz stimulus) amplitudes. LC analysis resulted in additional, albeit smaller, increases in amplitude (approximately 10%). FFRs to harmonically complex stimuli were characterized by a clear periodicity at the missing fundamental frequency (230 Hz). However, amplitudes varied according to the modulation depth of the stimulus and, in certain cases, actually exceeded that of the FFR response to a 230 Hz pure tone. The results demonstrate the effectiveness of cross-correlation and, to a lesser degree, latency compensation analysis, applied to two classes of brain-stem potentials. It is anticipated that such techniques will prove useful in the study of auditory signal processing at the level of the brain-stem.

Forecasting accuracy of alternative techniques: A comparison of US macroeconomic forecasts, with comment: Stephen K. McNees, with comment, Journal of Business and Economic Statistics 4 (1986) 5–23

This article examines the causal relationship between the energy consumption, electricity consumption and GDP in Russia by using time series data from 1990-2011 implying the Toda and Yamamoto approach, which is revised form of the Granger (1969) causality test (Econ. 66 (1995) 225). The maximum order of integration was determined by using PP and ADF unit root tests. The Toda and Yamamoto test is applied regardless of whether the series are I(0), I(1), or I(2), mutually cointegrated or non-cointegrated. The variables were estimated at level in the unrestricted lag-augmented VAR. The AIC, SC and LR lag criteria were used to determine the optimal lag length. The diagnostics tests were performed at the optimum lag selected by estimating the variables at level and confirmed the stability of the unrestricted VAR model. The empirical evidence showed that there exists a the bi-directional causality from electricity consumption to GDP that implies the validity of feedback hypothesis but no causality was found for GDP and energy consumption supporting the neutrality hypothesis. The estimated results confirmed that both the economic growth and electricity consumption empirically support each other and have a mutual and complementary relationship. But on another hand the energy sector of Russia has no impact on the economic growth for a period 1990-2011. Furthermore, if the Government of Russia devises policies to promote the access of energy and higher level of consumption, economic growth will not be affected.