Formula for the Number of Consecutively Accepted Tokens in Speculative Decoding
The number of consecutively accepted tokens from the start of a speculated sequence, denoted by , is determined by finding the index of the first rejected token. The formula is: Here, is the index of the token being evaluated (from to ), and is a variable drawn from the uniform distribution . The formula identifies the minimum index for which the rejection condition is met, and gives the count of all preceding, consecutively accepted tokens.

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Ch.5 Inference - Foundations of Large Language Models
Foundations of Large Language Models
Foundations of Large Language Models Course
Computing Sciences
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Formula for the Number of Consecutively Accepted Tokens in Speculative Decoding
Post-Acceptance Token Generation in Speculative Decoding
In an accelerated text generation method, a sequence of candidate tokens is proposed and then individually verified. The verification results for a sequence of 5 tokens, in order, are: [Accepted, Accepted, Rejected, Accepted, Accepted]. According to the rules of this method, a continuous block of accepted tokens from the beginning of the sequence is appended to the final output, and the process halts at the first rejected token. How many tokens from this proposed sequence will be appended to the final output?
Evaluating a Speculative Decoding Step
Diagram of Post-Acceptance Token Prediction in Speculative Decoding
Rationale for Consecutive Acceptance in an Accelerated Generation Method
You are implementing speculative decoding in a cus...
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Diagnosing a Speculative Decoding Slowdown in Production
Choosing τ and Model Roles for Low-Latency Speculative Decoding
Tuning Speculative Decoding Under a Fixed Verification Budget
Designing a Speculative Decoding Control Policy for a Latency-Sensitive Product
Root-Causing Low Speedup Despite Parallel Verification
Explaining a “Fast but Wrong” Speculative Decoding Regression
Interpreting a Speculative Decoding Trace and Identifying the Bottleneck
Acceptance and Rejection Criteria for Speculated Tokens
Formula for the Number of Consecutively Accepted Tokens in Speculative Decoding
In a system that uses a faster, smaller model to generate candidate tokens for a larger, more accurate model, a single token is being evaluated. The faster model assigns a probability of 0.8 to this token, while the more accurate model assigns it a probability of 0.6. For the acceptance check, a random number of 0.7 is drawn from a uniform distribution between 0 and 1. Based on this information, what is the outcome for this candidate token?
Speculative Decoding Acceptance Analysis
The Role of Randomness in Token Acceptance
Learn After
Set of Accepted Speculative Tokens
Calculating Consecutively Accepted Tokens
In a speculative decoding process, the number of consecutively accepted tokens from the start of a draft sequence, denoted by , is determined by finding the index of the first rejected token. The formula is: .
Given a draft sequence of 5 tokens () with the following randomly generated numbers () and probability ratios (), what is the calculated value of ?
- t=1: =0.4, =0.7
- t=2: =0.8, =0.9
- t=3: =0.6, =0.5
- t=4: =0.3, =0.8
- t=5: =0.7, =0.6
Consider the formula for calculating the number of consecutively accepted tokens in speculative decoding: . If the very first token in a drafted sequence (at index ) is rejected, this formula will yield a value of .