Not always getting same results as Natalie from bipm()

[Aariq]

This is documented in the tests on the ipm branch. I just want to have a space to keep notes here.

[Aariq]

Ok, here's the deal:

In natalie's original code, she calculates mean worker mass as the mean of the predicted masses of the hypothetical workers (~0.148)

  wkr_mass_mean <- mean(wkr_mass_f(wkr_size_1))

She uses the same mean mass for calculating pollen needed to produce 1 gram of worker

poln_per_wkrmass <- poln_per_cell / wkr_mass_mean

AND larval recruitment

wkr_larv <- daily_poln_return / (poln_per_wkrmass * wkr_mass_mean)

Meaning that the mean worker mass just canceled out in this equation. Then, after a phone conversation, Natalie told me that the mean worker mass should be the observed mean mass, not the mean mass of hypothetical workers. The observed mean is ~0.125.

I think that observed mean is only for the pollen per gram of worker estimation not for the larval recruitment calculation. So, new equation:

  poln_per_wkrmass <- poln_per_cell / 0.1254111

Now, the other confusion that I have is why isn't the worker mass in the denominator of the larval recruitment equation a vector of worker masses of different sizes?

The equation in the manuscript is written as:

f_x = p / pwg * y_x

where p is daily pollen return, pwg is the amount of pollen needed to make 1 gram of worker mass, and yx is the mass of the worker of size x.

In the code, p (daily_poln_return) is a vector of pollen returned by old workers of size i. pwg (poln_per_wkrmass) is a constant, as is y_x (wkr_mass_mean). Shouldn't daily pollen return be a constant and y_x be a vector?

[Aariq]

In natalie's updated manuscript the new larval recruitment equation is:

Where is the pollen cost per worker (equivalent to pwg above?).

[Aariq]

I think at this point, I probably am not going to be including Natalie's IPM in this package.