Raphael Nishimura's Avatar

Raphael Nishimura

@rnishimura.bsky.social

Survey methodologist and statistician at the Survey Research Center, Institute for Social Research, University of Michigan #survey | #sampling | #statistics | #RStats

3,040 Followers  |  322 Following  |  1,121 Posts  |  Joined: 19.08.2023  |  1.8004

Latest posts by rnishimura.bsky.social on Bluesky

One of my many pet peeves is people who denote survey sample sizes by N.
In surveys statistics, because we are dealing with finite population inferences, we reserve the notation N for population size and use n for sample size.

29.01.2026 19:47 β€” πŸ‘ 6    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Outdoor photo of the Convergence sculpture at ISR during a snowfall; a white text box reads β€œINSTITUTE FOR SOCIAL RESEARCH, Snow Flurries on Convergence.”

Outdoor photo of the Convergence sculpture at ISR during a snowfall; a white text box reads β€œINSTITUTE FOR SOCIAL RESEARCH, Snow Flurries on Convergence.”

Interior view of ISR's atrium with hanging plants and glowing pendant lights; white text box reads β€œINSTITUTE FOR SOCIAL RESEARCH, Atrium Glow.”

Interior view of ISR's atrium with hanging plants and glowing pendant lights; white text box reads β€œINSTITUTE FOR SOCIAL RESEARCH, Atrium Glow.”

Exterior photo of Perry Building with clear blue sky and red brick facade; white text box reads β€œINSTITUTE FOR SOCIAL RESEARCH, Perry Brick Red.”

Exterior photo of Perry Building with clear blue sky and red brick facade; white text box reads β€œINSTITUTE FOR SOCIAL RESEARCH, Perry Brick Red.”

Scenic rooftop view from ISR’s 6th floor showing a blue flag with a yellow M flying above Ann Arbor rooftops; white text box reads β€œINSTITUTE FOR SOCIAL RESEARCH, View From the 6th Floor.”

Scenic rooftop view from ISR’s 6th floor showing a blue flag with a yellow M flying above Ann Arbor rooftops; white text box reads β€œINSTITUTE FOR SOCIAL RESEARCH, View From the 6th Floor.”

The Shades of ISR Pantone ℒ️ palette πŸ’™ πŸ’›

22.01.2026 20:52 β€” πŸ‘ 5    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0

That's one Meng's point in his 2018 paper, isn't it?

22.01.2026 18:24 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Oh yeah, for sure, that's quite clear there. My point is that, as a general rule, statistically speaking, it just doesn't make sense to me, despite the empirical evidence. Bias in surveys doesn't typically scale with sample size, which is what the rule suggests.

22.01.2026 18:23 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

I always thought this rule that the total error is 2x reported MoE nonsensical, because bias in surveys doesn’t typically scale with sample size.
In fact, we usually see the opposite: smaller, more carefully designed prob samples tend to present smaller total error than large nonprob samples.

22.01.2026 16:59 β€” πŸ‘ 2    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0
We Are SRC
YouTube video by Survey Research Center, University of Michigan We Are SRC

The Survey Research Center at the Institute for Social Research of the University of Michigan turns 80 years old this year. Very proud to be part of this history!
youtu.be/giSsP7o4PZg?...

21.01.2026 00:32 β€” πŸ‘ 7    πŸ” 1    πŸ’¬ 0    πŸ“Œ 1
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E o mais importante, a descriΓ§Γ£o metodolΓ³gica da pesquisa:

13.01.2026 04:19 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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CenΓ‘rios de 2Β° turno: +

13.01.2026 04:19 β€” πŸ‘ 2    πŸ” 1    πŸ’¬ 1    πŸ“Œ 1
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CenΓ‘rios de 1Β° turno com Michelle: +

13.01.2026 04:19 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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Resultados da pesquisa Meio Ideia, primeira pesquisa prΓ©-eleitoral nacional de 2026 registrada no TSE (BR-06731/2026).
Pesquisa telefΓ΄nica com 2 mil entrevistas realizadas entre 08/01 e 12/01.
Perguntas espotΓ’nea e estimuladas com cenΓ‘rios de 1Β° turno com TarcΓ­sio e FlΓ‘vio): +

13.01.2026 04:19 β€” πŸ‘ 3    πŸ” 0    πŸ’¬ 2    πŸ“Œ 0

Sorry, I have just seen this.
I have just answered there.

05.01.2026 15:36 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

I'm just a mere survey statistician, I leave this sort of political analysis to my polisci colleagues πŸ˜›

31.12.2025 16:41 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

I think most of the major pollsters that use household, face-to-face data collection is using some sound and robust methodology.

31.12.2025 16:40 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

It's because, as in many other media outlets, they don't have anyone there with a good grasp of survey methods and they almost buy this pollster shameless self-promotion, mostly based on cherry picking and fallacious metrics.

31.12.2025 16:37 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

As usual, regardless of the poll result, I'd always take any of their polls with a huge grain of salt. Maybe all the salt in the oceans? πŸ˜…

31.12.2025 16:35 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

It essentially depends on two things: the amount of measurement error and how correlated the auxiliary variable is with the survey variables.
Just as with missing data (e.g., coverage, sampling or nonresponse), the math doesn't care about what is the source of error!

31.12.2025 13:46 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Here are the slides: aapor.confex.com/aapor/2025/m...

31.12.2025 13:41 β€” πŸ‘ 3    πŸ” 0    πŸ’¬ 1    πŸ“Œ 1

I did a whole simulation on this and presented at AAPOR earlier this year!

31.12.2025 13:40 β€” πŸ‘ 4    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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Merry Christmas! πŸŽ…πŸŽ„

25.12.2025 15:52 β€” πŸ‘ 13    πŸ” 2    πŸ’¬ 1    πŸ“Œ 0

At this point, people shouldn't be surprised by this. Their methodology is crap, so you get this kind of unstable and unreliable estimates. You all should just stop fooling yourselves.

20.12.2025 21:00 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

The point here is: they were relying A LOT on weighting to adjust their heavily skewed sample towards Trump voters. Is their methodology still producing this kind of sample? And can the weights sufficiently address this issue?

20.12.2025 01:16 β€” πŸ‘ 7    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0

So, I have no idea whatever kind of adjustment they are making to obtain the result that got them the title of "2020 America's most accurate pollster". And why can't we replicate these weights with their microdata following what is described in their stated methodology? +

20.12.2025 01:16 β€” πŸ‘ 7    πŸ” 2    πŸ’¬ 1    πŸ“Œ 0

I tried several different versions of weighting by those variables, but in none of them I was able to replicate their final estimate of Biden 52 Trump 47. In fact, in none of the weights, I was even able to get Biden ahead of Trump. The closest I got was Biden 49 Trump 50. +

20.12.2025 01:16 β€” πŸ‘ 6    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0
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Also, I tried to replicate their weight according to the stated methodology. There is a discrepancy here because in one it's mentioned they weighted by 2016 recall vote, but not in the other. From other polls of the same pollster, I'm pretty sure they did weight by recall vote. +

20.12.2025 01:15 β€” πŸ‘ 5    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0

On one hand, that's good: they are doing what they are supposed to be doing. On the other hand, if your sample data is usually THAT skewed that you are relying that much in the weights, that can be very problematic if for any given race the weights don't manage to correct that.

20.12.2025 01:12 β€” πŸ‘ 7    πŸ” 2    πŸ’¬ 1    πŸ“Œ 1

The unweighted result is Trump 66% Biden 33% (!!!). Recall 2016 vote is 70% Trump 30% Clinton. The weights are doing A LOT of work here! +

20.12.2025 01:11 β€” πŸ‘ 9    πŸ” 2    πŸ’¬ 1    πŸ“Œ 0
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Below is their 2020 national poll methods per Roper Center. Not much different to what a lot of other pollster are doing. However, if you look at the polling microdata also in Roper...+

20.12.2025 01:11 β€” πŸ‘ 6    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0

Let me bring that information here 🧡

20.12.2025 01:10 β€” πŸ‘ 13    πŸ” 3    πŸ’¬ 1    πŸ“Œ 0

Congrats!!

06.12.2025 04:18 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

@badsurveyq.bsky.social

04.12.2025 22:26 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

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