The phrase "a probit value" is correct and usable in written English.
It is typically used in statistics and econometrics to refer to the output of a probit regression model, which estimates the probability of a binary outcome.
Example: "The analysis revealed a probit value of 0.75, indicating a high likelihood of the event occurring."
Alternatives: "a probit coefficient" or "a probit estimate".
For example, if half the subjects in a caries trial had one particular site carious, the probit value would be 0, since half the area in a standard normal distribution falls below a z score of 0. When using standard normal values, negative scores can occur.
For example, if a particular surface scored 1 and half the subjects studied had caries, the probit value would be 0, since half of the area in a standard normal curve falls below a z score of 0. When the constant is added, the transformed value for the proportion becomes 5.
If the observed proportion of individuals in whom the site was carious was 0.84, the probit value would be 0.34, i.e. a z score of 1, which would give a transformed value of 6.
From the estimation results, we compute the latent index of Graduate Skills Requirements (GSR) as the predicted probit value.
Open image in new window Fig. 2 Log-probit model regression lines for log concentration (actual) versus probit values for Oreochromis niloticus following 96-h exposure to technical grade (T) and formulation (F) of cypermethrin.
Log-probit model regression lines for log concentration versus probit values of mortality for O. niloticus following 96-h exposure to technical grade (T) and formulation (F) of cypermethrin were parallel to each other (Fig. 2).
Since choice performance is expressed in % for each of the two alternatives and the model requires the calculation of differences between the choice performances, the % values are first linearized by calculating the corresponding probit values and then subtracting these probits.
Significant differences in LT25 and LT50 values between treatments were determined based on probit values with non-overlapping 95% Fiducial Limits [ 36].
The probit values were plotted against the logarithmic values of concentrations of the test samples and a linear regression curve was established in order to calculate the EC50 (μg/ml), which is the amount of sample necessary to decrease by 50% the absorbance of DPPH [ 11].
For the evaluation of 35-day LC50 values, a probit analysis was used based on mortality at different terbuthylazine-2-hydroxy concentrations.
