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Using exponential probability distribution (explain): We will set loc=1 since the new members are likely to quit during the first month. But, what value of scale maximizes the log-likelihood of the data? As an example, compute the log-likelihood of this dataset using a scale value of 4. The observed data here is the number of months a person remains enrolled before eventually quitting. Make sure that your data is the mem_duration for individuals with status=="Q".

User Torinthiel
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Final answer:

The exponential distribution is used to model time until an event occurs, characterized by more small values and fewer large ones. Optimization techniques are needed to find the scale value that maximizes the log-likelihood of a dataset. Assuming a scale of 4, one could calculate the log-likelihood for a dataset given the enrollment durations.

Step-by-step explanation:

The exponential distribution is a continuous probability distribution commonly used to model the time between events in a Poisson process. In particular, it is often employed to quantify the length of time until a certain event happens, making it useful in various fields such as engineering, physics, and business. For instance, it can model the time before a customer quits a membership or service. For the exponential distribution, the probability density function (PDF) is given by f(x) = me-mx where m is the decay parameter, often expressed as 1/μ, with μ being the mean of the distribution.

To find the value of the scale that maximizes the log-likelihood of the data for a given dataset, one would typically employ optimization techniques. However, without the actual data, we cannot compute the exact value that maximizes this log-likelihood. Assuming we use a scale value of 4, with loc value set to 1, we could calculate the log-likelihood for the given dataset if the number of months a person remains enrolled before quitting is known. In practical applications, the 'scale' parameter corresponds to the mean of the exponential distribution.

The logarithm of the likelihood function can be written as the sum of the logarithms of the individual probabilities of the observed data points under the assumed model. Assuming independence between the observations (a common assumption in such analyses), the log-likelihood L can be expressed as L = Σ log(f(xi)) for all data points xi in the dataset of individuals with status "Q".

User Eric Sites
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