Comment: Demystifying Double Robustness: A Comparison of Alternative Strategies for Estimating a Population Mean from Incomplete Data

Abstract Considerable recent interest has focused on doubly robust estimators for a population mean response in the presence of incomplete data, which involve models for both the propensity score and the regression of outcome on covariates. The usual doubly robust estimator may yield severely biased inferences if neither of these models is correctly specified and can exhibit nonnegligible bias if the estimated propensity score is close to zero for some observations. We propose alternative doubly robust estimators that achieve comparable or improved performance relative to existing methods, even with some estimated propensity scores close to zero.

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Individual Differences in Mental Rotation

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000184 ◽

2013 ◽

Vol 60 (3) ◽

pp. 164-171 ◽

Cited By ~ 20

Author(s):

Peter Khooshabeh ◽

Mary Hegarty ◽

Thomas F. Shipley

Keyword(s):

Individual Differences ◽

Mental Rotation ◽

Response Times ◽

Task Demands ◽

Mental Rotation Task ◽

Imagery Ability ◽

Alternative Strategies

Two experiments tested the hypothesis that imagery ability and figural complexity interact to affect the choice of mental rotation strategies. Participants performed the Shepard and Metzler (1971) mental rotation task. On half of the trials, the 3-D figures were manipulated to create “fragmented” figures, with some cubes missing. Good imagers were less accurate and had longer response times on fragmented figures than on complete figures. Poor imagers performed similarly on fragmented and complete figures. These results suggest that good imagers use holistic mental rotation strategies by default, but switch to alternative strategies depending on task demands, whereas poor imagers are less flexible and use piecemeal strategies regardless of the task demands.

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Reversion Toward the Mean Independently of Regression Toward the Mean

Methodology ◽

10.1027/1614-2241.5.1.3 ◽

2009 ◽

Vol 5 (1) ◽

pp. 3-6 ◽

Cited By ~ 2

Author(s):

Merton S. Krause

Keyword(s):

Random Error ◽

Evaluation Studies ◽

Internal Validity ◽

Intervention Evaluation ◽

Population Mean ◽

Experimental Intervention ◽

Sample Data ◽

The Mean ◽

Regression Toward The Mean

There is another important artifactual contributor to the apparent improvement of persons subjected to an experimental intervention which may be mistaken for regression toward the mean. This is the phenomenon of random error and extreme selection, which does not at all involve the population regression of posttest on pretest scores but involves a quite different and independent reversion of subjects’ scores toward the population mean. These two independent threats to the internal validity of intervention evaluation studies, however, can be detected and differentiated on the sample data of such studies.

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ANALISIS KINERJA STRATEGI PEMASARAN USAHA KERAJINAN KETAK DI KABUPATEN LOMBOK TENGAH

Jurnal Ilmu Pemerintahan Suara Khatulistiwa ◽

10.33701/jipsk.v3i2.294 ◽

2018 ◽

Vol 3 (2) ◽

Author(s):

H.L Ahmad Murdani

Keyword(s):

Product Market ◽

Horizontal Merger ◽

Case Method ◽

Alternative Strategies ◽

Market Expansion ◽

Descriptive Research ◽

Method Approach

Ketak handicraft is one of any other superior handicraft in Lombok Tengah Regency, as one of any other revenue generator for Lombok Tengah regency and to increase the prosperity of people in this industry, it is needed to find out the ways and strategies to improve the performance of this business. This research was categorized as a descriptive research which used case method approach, it was aimed to find out the position of ketak handicraft among handicraft industry in Lombok Tengah based on recent performance and to identify alternative strategies which can be chosen in order to improve the performance of this industry. In order to find out the position of ketak handicraft business, it was used BCG Agam analysis and based on this position the strategy for improving this business was selected based on this analysis, the position of third business was in the stars position, where alternative strategies that can be chosen were: (a) development of the existing product (market expansion for the existing product); (b) diversification; (c) horizontal merger. Suggestion recommended was to apply one of these strategies based on analysis that had been conducted.

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