Jon Whiteley explains. [MUSIC] Hi guys, welcome to the 23rd lecture of the course Biological Diversity, Theories, Measures and Data sampling techniques. Notice that this equation resolves to Jaccard’s index when just presence or absence data is available. One of the best ways to assess employee diversity is to use quantitative measurements. Fish and Wildlife Service (USFWS) has documented a series of HSI models for a wide variety of species (FWS/OBS-82/10). Missed the LibreFest? Biological communities vary in the number of species they contain (richness) and relative abundance of these species (evenness). Measuring workplace diversity can be accomplished using a number of methods—simply walking through your office or plant and noticing the many differences between employees, or generating an employee census report sorted by age, race, ethnicity, sex and disability. So let’s look at a simple example of how these indices allow us to compare similarity between three sites. (Copenhagen) vol. The first step for an inclusive company culture is to measure D&I. Typically, the value of a diversity index increases when the number of types increases and the evenness increases. Figure 1. These models include the log normal, geometric, logarithmic, and MacArthur’s brokenstick model. Abundance curves offer an alternative to single number diversity indices by graphically describing community structure. The primary interface between timber and wildlife is habitat, and habitat is simply an amalgam of environmental factors necessary for species survival (e.g., food or cover). If abundance is primarily concentrated into one species, the index will be close to zero. Quantitative Measures • Diversity of leadership board: An important measurable differentiator for an inclusive organization. The similarity ratio is: where yki is the abundance of the kth species at site i (sites i and j are compared). Suitability index graph for percent canopy cover. W.K. Quantitative. The quantitative indices return the same conclusions as the qualitative indices. We want to compute Simpson’s D for this hypothetical community with three species. These are metrics that can be evaluated using numbers. Have questions or comments? Habitat suitability index (HSI) models provide a numerical index of habitat quality for a specific species (Schamberger et al. W.F. Top tips for measurement and reporting: 1. Today we will talk about qualitative measures of biodiversity. Those same organisations are now looking to measure the return on this investment, to see whether a diversity strategy really does add value to the overall business strategy. E.H. Simpson, “Measurement of Diversity,” Nature 163, 1949, p. 688. Press, 1988. An equivalent and computationally easier formula is: where N is the total number of species and ni is the number of individuals in species i. The Shannon-Weiner index (Barnes et al. Genetic diversity can be defined in multiple ways, and currently lacking in ecology is a consensus on how to measure genetic diversity. Measuring workplace diversity can be accomplished using a number of methods---simply walking through your office or plant and noticing the many differences between employees, or generating an employee census report sorted by age, race, ethnicity, sex and disability. A diversity index is a quantitative measure that reflects the number of different species and how evenly the individuals are distributed among those species. The higher the value of this inverse index the greater the diversity. Figure 5. We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. To derive the ILD we created a database of time-series data on language demographics, which we believe to be the world’s largest. The Habitat Evaluation Procedures (HEP) (Schamberger and Farmer 1978) were developed in response to the need to document the non-monetary value of fish and wildlife resources. The U.S. The data received is statistically valid and can be generalized to the entire user population. As you can see, the more life requisites included in the model, the more complex the model becomes. Diversity is variety and at its simplest level it involves counting or listing species. A modified of version (Bray-Curtis 1957) of the Sorenson’s measure, which is sometimes called the Sorenson’s quantitative index or the Bray-Curtis index (Magurran 1988) CN = () N N. a b jN + 2. Manage. Quantitative Measurement – goal is measured by a metric or statistic. An HSI model must begin with habitat use information, understanding the species needs in terms of food, water, cover, reproduction, and range for this species. For this reason, Simpson’s index is usually expressed as its inverse (1/D) or its compliment (1-D) which is also known as the Gini-Simpson index. This is the website of the Quantitative Studies of Diversity and Inclusion (QSDI) initiative at the City College of New York, part of the CUNY school system.Our goal is to establish CUNY as the world's premier hub for Diversity & Inclusion research, combining quantitative and qualitative methods. Richness, the compliment to Simpson’s D, and Shannon’s H’ are computed for both stands. Figure 2. In addition to helping us measure the gaps, it also helps identify what is working well. ... perceptions of the climate for diversity. We just described their characteristics. Watch the recordings here on Youtube! The percent similarity index is: Again, notice how this equation resolves to Sørenson’s index with qualitative data only. Indices of diversity vary in computation and interpretation so it is important to make sure you understand which index is being used to measure diversity. These two diversity indices incorporate both richness and evenness. Quantitative measurements are aligned with basic principles of affirmative action. By examining the present characteristics of the managed stands, understanding the future response due to management, and comparing those with the requirements of specific species, we can achieve habitat manipulation together with timber management. Horizontal and structural diversity are important. This compliment represents the probability that two individuals randomly selected from a sample will belong to different species. van Tongeren, “Cluster Analysis,” Data Analysis in Community and Landscape Ecology, Eds. However, the first sample has more evenness than the second. Legal. 1998) was developed from information theory and is based on measuring uncertainty. 3, 1980, pp. Quantitive measurements are also: record time, distance, temperature, density... On the second example there are blue, red and yellow birds. Workforce composition. A diversity index is a quantitative measure that reflects the number of different species and how evenly the individuals are distributed among those species. It gives equal weight to those species with few individuals as it does to a species with many individuals. Population diversity: variations observed quantitative ecological parameters such as frequency, density, abundance etc. Table 1. Quantitative measurements also can measure supplier diversity and the results of multicultural marketing efforts. • Grievances, complaints, and labor relations issues: Inclusivity should result in a more transparent culture and better employee relations resulting in a reduction of grievances. Typically, the value of a diversity index increases when the number of types increases and the evenness increases. For each of these four winter cover variables (V1, V2, V3, and V4), suitability index graphs were created to examine the relationship between various conditions of these variables and suitable habitat for the marten. There are also indices that compare the similarity (and dissimilarity) between sites. Notice that any canopy cover less than 25% results in unacceptable habitat based on this variable alone. Because Stand A displays greater evenness it has greater overall diversity than Stand B. Both of these qualitative indices declare that sites 1 and 3 are the most similar and sites 2 and 3 are the least similar. U.S.D.I. The discomfort is not surprising. It is very important to clearly state which version of Simpson’s D you are using when comparing diversity. Diversity of organisms and the measurement of diversity have long interested ecologists and natural resource managers. Additionally, all winter habitat requirements are satisfied in boreal evergreen forests. Quantitative and qualitative information are helpful for identifying trends and areas for improvement within a workplace. First of all, we need to ask what is the purpose of the research. The key component to habitat for most wildlife is vegetation, which provides food and structural cover. With businesses expanding globally and regionally, it's important to maintain a level of diversity within the workplace. In the abundance distribution graph, richness can be compared on the x-axis and evenness by the shape of the distribution. Bird species diversity nesting across a forest to field gradient (After Strelke and Dickson 1980). 1982) and in general assume a positive, linear relationship between carrying capacity (number of animals supported by some unit area) and HSI. Let’s compute the Shannon-Weiner diversity index for the same hypothetical community in the previous example. The benefits of diversity measurement In the post #metoo world, diversity and inclusion are integral to most conversations about positive work environments. A.W. Human resources recruiters and retention specialists gather and tabulate such information for maintaining competitive compensation and benefits. If quantitative data are available, a similarity ratio (Ball 1966) or a percentage similarity index, such as Gauch (1982), can be computed. In Stand B, species 1 has the most individuals, with the remaining nine species having a substantially smaller number of individuals per species. R.H.G. ... Michele was responsible for building strategies related to university hiring, diversity recruiting, succession and workforce planning, employee referral programs, and pre-hire assessments. Two stands comparing richness, Simpson’s D, and Shannon’s index. Many quantitative measures focus on the amount or number of persons in an organization based on traditional affirmative action definitions. In the second sample, most of the individuals are sugar maples with fewer beech and yellow birch trees. This ability is important because the relative abundance of different kinds of bacteria can be … Qualitative and quantitative data helps identify and understand the key actions and measures for a successful D&I programme, improved business performance and the best return on investment for D&I efforts. An HSI model synthesizes habitat use information into a framework appropriate for fieldwork and is scaled to produce an index value between 0.0 (unsuitable habitat) to 1.0 (optimum habitat), with each increment of change being identical to another. Although quantitative measures are also used in the social sciences, qualitative measures help investigators to understand human experiences on a deeper level. Figure 3. Unless otherwise noted, LibreTexts content is licensed by CC BY-NC-SA 3.0. Companies have started to recognize the importance of diversity and inclusion—but few have found ways to hold themselves accountable to real change. Quantitative Research. Figure 4. For more information contact us at info@libretexts.org or check out our status page at https://status.libretexts.org. Aedrake09. Species diversity: Measures the species number variations in different genera at a particular habitat (5). Not only do these indices compare number of similar and dissimilar species present between two sites, but also incorporate abundance. Creating prescriptions that combine timber and wildlife management objectives are crucial for sustainable, long-term balance in the system. The Jaccard index (1912) compares two sites based on the presence or absence of species and is used with qualitative data (e.g., species lists). This ability is important because the relative abundance of different kinds of bacteria can be critical for describing community changes. Such a plot allows the user to compare not only relative richness but also evenness. Since the sum of the pi’s equals unity by definition, the denominator equals the weighted geometric mean of the pi values, with the pi values being used as weights. Danske Vidensk. We need information on the habitat required by the wildlife species of interest and we need to be aware of how timber harvesting and subsequent regeneration will affect the vegetative characteristics of the system. Diversity and inclusion metrics are used to identify risk areas, prioritise initiatives, set targets and other program goals, assign accountability, and measure the impact of initiatives. FWS/OBS-82/10.11., 1982,9 pp. Those same organisations are now looking to measure the return on this investment, to see whether a diversity strategy really does add value to the overall business strategy. diversity and inclusion practitioners feel distinctly less competent in this area than in other less-quantitative aspects of their work. Top tips for measurement and reporting: 1. We could also use all of 5 senses to describe them. Although London Deanery reports that quantitative research is commonly used in scientific and clinical research, it can also be used by organizations to assess employee diversity. Simpson’s index is a weighted arithmetic mean of proportional abundance and measures the probability that two individuals randomly selected from a sample will belong to the same species.