- Thread starter kjebr
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Hi, I'm trying to calculate the standard deviation of a dataset for my uni meta analysis from this formula. How would I go about calculating the inverse of phi Φ? Would I just substitute 1.618033 which is what the value of phi is according to google?

View attachment 4083

View attachment 4083

a = maximum value

n = number of participants

Curious where you are getting this formula from. Can you provide a link, so we can see how it was presented. I am not imagining phi is a constant or irrational number you are supposed to input, I feel like it may be derived from your data.

it's equation 9

?

Φ symbol represents the**cumulative distribution function** (CDF) of a standard normal distribution, Φ(z). In *R*, the CDF of the standard normal distribution is implemented in the pnorm function. But you may want the inverse. But I could be making stuff up here

Φ symbol represents the

Φ symbol represents the

You would input what's in the parenthesis into the function. But pnorm is the cdf of the normal and we want the inverse of that. It sounds like you're using R so use qnorm instead.