Statistical Analysis of the Additive and Multiplicative Hypotheses of Multiple Exposure Synergy for Cohort and Case-Control Studies

This paper considers hypotheses tests for synergistic relationships in epidemiological studies. Two hypotheses are considered. First, I develop tests of the additive hypothesis which states that the combined risk from two sources of exposure is the sum of each risk taken separately. I then develop tests for the hypothesis that a multiplicative relationship exists for the risks, i.e., that the combined risk is consistent with the multiplication of the individual risks. Following standard practice in epidemiological studies I consider tests for both case-referent and cohort (standardized mortality rate) type studies

Simulation of the Demand for Electricity Under Alternate Rate Structures

This paper reviews the theory of price specification and considers the comparative static analysis of demand subject to alternative rate schedules. An econometric analysis of the 1975 Washington Center for Metropolitan Studies survey resolves four empirical issues related to the estimation of the demand for electricity: (1) measured average price and measured marginal price are statistically endogenous so that least squares technique s are not appropriate for the determination of price and income elasticities, (2) while the rate structure premium (RSP ) has established theoretical merit its statistical contribution is negligible, (3) consumer behavior in the demand for electricity follows the marginal price rather than the average price specification, and (4) estimates of price responsiveness are not statistically different using the tail-end price rather than the true marginal price. We demonstrate a practical way of making probabilistic comparisons between alternative rate schedules which is applied in several examples to illustrate the prevalence of block switching. The methodology is easily applied to inverted tariff schedules even when structural parameters have been determined from a cross-section of individuals who face declining block rates

Evidence of Block Switching in Demand Subject to Declining Block Rates - A New Approach

This paper considers the problem of forecasting demand subject to a non-linear rate schedule. We develop an empirical model of electricity demand subject to a quantity determined rate schedule and suggest a new procedure to estimate population taste variation. Using micro-level data from the 1975 Washington Center for Metropolitan Studies (WCMS) survey, we provide evidence on the prevalence and extent of block switching

Market Barriers to Conservation: Are Implicit Discount Rates Too High?

This paper reconsiders whether implicit discount rates, generally cited as a market barrier to conservation, are really too high, and demonstrates that probabilistic choice studies of consumer durable purchases and hedonic housing price regression studies measure similar but non-identical discount factors. Four hedonic regression studies are reviewed which attempt to ascertain whether and to what extent the housing market capitalizes energy conservation investments. A theoretical model is presented which links the probabilistic choice and hedonic regression methods and shows how using results from both studies allows measurement of individual discount rates without bias. The paper identifies several factors which cause the degree of capitalization to differ from unity, resulting in consumer decisions which are rational from the individual perspective, but which can lead to low levels of social conservation

Stochastic Simulation of Labor Demand Under Wage Subsidization

The impact of a system of wage subsidies, funded by unemployment insurance vouchers, is evaluated by combining a set of disaggregated industry labor demand models with an input/ output model. The program is shown to increase employment initially by lowering the cost of labor to firms. The disposable income of workers is increased which acts as a macroeconomic stimulus. The success of the subsidy program depends to some extent on the degree to which demand induced by greater consumer spending is able to sustain higher employment levels. Overall, it is estimated that a four-quarter wage subsidy equivalent to 30 percent of prevailing industry wages results in a long run decline in unemployment in excess of 1 percent

The Heterogenous Logit Model

Probabilistic choice systems in the generalized extreme value (GEV) family embody two restrictions not shared by the covariance probit model. First, the unobserved components of random utility are homoscedastic across individuals and alternatives. Second, the degree of similarity among alternatives is also assumed to be constant across individuals. This paper considers extensions to models in the GEV class which relax these two restrictions. An empirical application concerning the demand for cameras is developed to demonstrate the potential significance of the heterogenous logit model

Experimental Estimates of the Impact of Wage Subsidies

The effects of a wage subsidy program on the duration of insured unemployment are investigated using experimental data. Participation in the experiment was voluntary and about one third of the subjects refused to take the subsidy voucher offered to them. Because subsidies appear to have stigmatic effects which tend to lower participation rates by high-skilled workers, experimental participants have longer average durations of unemployment than non-participants. However, correcting for self-selection, we find that wage subsidies can substantially increase a participant's probability of reemployment. Subsidies are also compared to a search bonus proposal which is also cost effective, but, due to differences in participation patterns, has rather different effects

Participation in Direct Legislation: Evidence from the Voting Booth

This study considers individual voting behavior on propositions. After controlling for voter and election specific attributes, we determine the effects of proposition attributes, such as proposition position and readability on roll-off and voter fatigue. If proposition attributes affect voting behavior and if their attributes can be influenced by supporters, including interest groups, then any such potential advantages should be ameliorated in the interest of "equal" political representation. As an example, advantages of ballot position can be minimized by modifying the linkage between the qualification sequence and the ballot sequence. Using individual level ballot data taken from Los Angeles county, we find that the proposition position is negatively related to the probability of voting on a proposition and the probability of voting "Yes" on bonds and initiatives. We also find that reading ease is positively related to the probability of voting on a proposition and the probability of voting "Yes" on bonds and initiatives

Comparing Absentee and Precinct Voters: A View Over Time

This paper examines the trend in absentee voting over the last thirty years in California. With the liberalization of absentee voting laws and practices, an increase in the numbers of absentee voters quickly followed. Absentee voters have already demonstrated their ability to influence the outcomes of local elections. An open question is what will become of absentee voters in the future. If they are the model for "voting at home," and if technological advances allow such, then the behavior of current absentee voters may be indicative of the future electorate. The increasing trend of voters opting for absentee ballots is analyzed by using GLS on a random effects time-series cross-section model with county level data. The focus is on identifying structural factors such as changing voter demographics that have influenced the decision of voters to cast absentee ballots. Thirty-three recent state-wide elections in California are the basis for this analysis, covering the statewide primary and general elections from November 1962, through November 1994. We find that the impact of demographics and time trends on absentee voting differ between general and primary elections. In addition, we find that a 1977 liberalization law in California had the effect of accelerating the usage of the absentee format. Finally, we conclude that absentee and precinct voting are substitutes in general elections but complements in primary elections