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Unveiling Hidden Neural Codes: SIMPL – A Scalable and Fast Approach for Optimizing Latent Variables and Tuning Curves in Neural Population Data

Dr. Rishabh Pathak
This research paper presents SIMPL (Scalable Iterative Maximization of Population-coded Latents), a novel, computationally efficient algorithm designed to refine the estimation of latent variables and tuning curves from neural population activity. Latent variables in neural data represent essential low-dimensional quantities encoding behavioral or cognitive states, which neuroscientists seek to identify to understand brain computations better. Background and Motivation Traditional approaches commonly assume the observed behavioral variable as the latent neural code. However, this assumption can lead to inaccuracies because neural activity sometimes encodes internal cognitive states differing subtly from observable behavior (e.g., anticipation, mental simulation). Existing latent variable models face challenges such as high computational cost, poor scalability to large datasets, limited expressiveness of tuning models, or difficulties interpreting complex neural network-based functio...
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Lottery Methods

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Dr. Rishabh Pathak

Lottery methods are a type of simple random sampling technique where each element in the population is assigned a unique identifier (such as a number or a ticket), and a random selection process resembling a lottery is used to choose the sample. This method ensures that every element in the population has an equal probability of being selected for the sample. Here are some common lottery methods used in sampling:


1.    Traditional Lottery Draw:

o  In a traditional lottery draw, each element in the population is assigned a unique number or ticket. These numbers are placed in a container (e.g., a hat, a bowl, or a drum). A person then randomly selects numbers from the container without looking, ensuring randomness in the selection process. This method mimics a lottery draw where each element has an equal chance of being chosen.

2.    Random Number Generator:

o    With advancements in technology, random number generators are commonly used to conduct lottery-based sampling. Random number generators are algorithms or software programs that generate a sequence of random numbers. Researchers can assign numbers to elements in the population and use a random number generator to select sample elements. This method ensures unbiased and random selection.

3.    Electronic Raffle Systems:

o    Electronic raffle systems are modern tools that facilitate lottery-based sampling in a digital format. These systems use electronic devices or software to conduct random draws. Researchers input the population data into the system, and the electronic raffle system selects sample elements randomly. Electronic raffle systems offer efficiency and accuracy in the sampling process.

4.    Online Random Selection Tools:

o  Online random selection tools are web-based applications or websites that enable researchers to conduct lottery-based sampling online. These tools use algorithms to generate random selections from a given population. Researchers can input the population data, specify the sample size, and use the online tool to perform the random selection process. Online random selection tools are convenient for virtual research settings.

5.    Physical Lottery Machines:

o  Physical lottery machines are mechanical devices designed for conducting random draws. These machines are commonly used in lottery events and can also be employed for sampling purposes. Researchers can load the identifiers of population elements into the machine, operate it to select sample elements randomly, and ensure fairness in the selection process. Physical lottery machines provide a tangible and transparent way of conducting random sampling.

By utilizing lottery methods in sampling, researchers can achieve randomness and fairness in selecting samples from populations. Whether through traditional lottery draws, random number generators, electronic raffle systems, online tools, or physical machines, lottery methods offer a systematic approach to simple random sampling, ensuring that each element in the population has an equal opportunity to be included in the sample.

 

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