Clark & Hatfield, Kendler Studies PDF

Clark & Hatfield: The primary aim of the study conducted by Russell D. Clark and Elaine Hatfield was to investigate gender differences in receptivity to sexual offers. Specifically, the researchers sought to understand how men and women respond to different types of sexual propositions, such as g...

Clark & Hatfield: The primary aim of the study conducted by Russell D. Clark and Elaine Hatfield was to investigate gender differences in receptivity to sexual offers. Specifically, the researchers sought to understand how men and women respond to different types of sexual propositions, such as going out on a date, going to an apartment, or engaging in sexual intercourse. The study aimed to challenge existing stereotypes about male and female sexual behavior and to provide empirical data on these differences. Method The study was conducted in two phases (Study #1 in 1978 and Study #2 in 1982) at Florida State University. The methodology involved the following key components: 1. Participants: The subjects included 48 men and 48 women who were approached on campus. The confederates (individuals making the requests) were approximately 22 years old and varied in physical attractiveness. 2. Procedure: Confederates approached members of the opposite sex who were strangers and made one of three types of requests: ○ "Would you go out with me tonight?" ○ "Would you come over to my apartment tonight?" ○ "Would you go to bed with me tonight?" 3. The requests were made in five different locations on campus, and the confederates were instructed to approach only those subjects they found attractive enough to potentially engage in sexual activity with. 4. Design: The study utilized a 2 x 3 factorial design, with the sex of the requestor (male or female) and the type of request (date, apartment, bed) as the independent variables. Findings The findings from both studies indicated significant gender differences in responses to the sexual propositions: In Study #1 (1978), men were more likely to accept all types of invitations compared to women (65% of men versus 21% of women accepted the requests). The results showed that while both genders were willing to go out on a date, only men agreed to go to the female's apartment or to bed with her. In Study #2 (1982), similar results were obtained, with men again showing a higher likelihood of accepting the requests (63% of men versus 17% of women). The interaction between the sex of the requestor and the type of request was significant, reinforcing the findings from the first study. Strengths 1. Experimental Design: The use of a controlled experimental design allowed for the systematic investigation of the variables involved, providing clear insights into the differences in sexual receptivity between genders. 2. Naturalistic Setting: Conducting the study in a naturalistic setting (on a college campus) increased the ecological validity of the findings, as the interactions were more reflective of real-life social situations. Limitations 1. Sample Size and Diversity: The study's sample was limited to college students at a single university, which may not be representative of the broader population. This lack of diversity could limit the generalizability of the findings to other age groups or cultural contexts. 2. Ethical Considerations: The nature of the requests made by the confederates raises ethical concerns regarding consent and the potential emotional impact on the subjects. While the subjects were debriefed afterward, the initial approach could have caused discomfort or distress, particularly for women who were approached with sexual propositions. ​ Kendler: The study aimed to investigate the heritability of major depression and to explore potential sex differences in genetic risk factors for the disorder. By utilizing a large sample of twins, the researchers sought to replicate previous findings and provide a more comprehensive understanding of the genetic and environmental influences on major depression. ​ Method ​ The study involved a population-based sample of twins from the Swedish Twin Registry. Data collection was performed through computer-assisted telephone interviews, which aimed to screen all twins regardless of their previous participation in the registry. The assessment of major depression was conducted using the Composite International Diagnostic Interview Short Form (CIDI-SF), which was adapted to evaluate lifetime prevalence rather than just 12-month prevalence. The sample included 8,056 twins who completed the major depression section, and the researchers also accounted for individuals who had a history of antidepressant usage. ​ The heritability estimates were derived from comparing the rates of major depression in monozygotic (identical) and dizygotic (fraternal) twins. The study also examined the potential influence of measurement error and the presence of mania in the sample. ​ Findings ​ The study found that the heritability of major depression was estimated at 40% in women and 31% in men, which aligns closely with previous studies. This suggests that genetic factors play a significant role in the development of major  depression, with a slightly higher influence in women. The results indicated no major cross-population differences in the heritability of major depression among European or European-derived populations. Additionally, the study highlighted the importance of using a robust sample size to achieve reliable estimates, as smaller studies had shown inconsistent results regarding sex differences in genetic risk factors. ​ Strengths 1. Large Sample Size: The study utilized a substantial sample of over 8,000 twins, which enhances the reliability and generalizability of the findings. A larger sample allows for more accurate estimates of heritability and increases the statistical power to detect differences between groups. 2. Methodological Rigor: The use of a standardized diagnostic tool (CIDI-SF) for assessing major depression, along with a structured data collection process, adds to the validity of the findings. The study's design, which included efforts to interview twins close in time, helps mitigate potential biases related to recall or reporting. ​ Limitations 1. Cross-Sectional Design: The assessment of lifetime history of major depression at a single point in time may not capture the full complexity of the disorder. This design limits the ability to account for changes in symptoms over time and may introduce measurement error, which could confound the results. 2. Inclusion of Individuals with Mania: The study included individuals with a history of mania, which may complicate the interpretation of the heritability estimates. Since the presence of mania can indicate bipolar disorder, the findings may reflect a broader spectrum of mood disorders rather than solely unipolar major depression. This could lead to an overestimation of genetic influences if not properly accounted for.