Package 'simfit'

Title: Test Model Fit with Simulation
Description: Simulates data from model objects (e.g., from lm(), glm()), and plots this along with the original data to compare how well the simulated data matches the original data to determine model fit.
Authors: James Green [aut, cre]
Maintainer: James Green <[email protected]>
License: GPL-3
Version: 0.1.0
Built: 2024-11-13 03:43:15 UTC
Source: https://github.com/cran/simfit

Help Index


Fit Simulated Data to a Model.

Description

Fit Simulated Data to a Model.

Usage

pred.fit(model, xpred = NULL, ci = 0.95, npoints = "same")

Arguments

model

a model object, from (eg) lm

xpred

the predictor for the x axis on the graph

ci

confidence interval for fit curve (defaults to 0.95)

npoints

number of data points for fit line. Either specify a number, or "same" will return a simulation of the same size as the original dataset.

Value

predicted data

Examples

## Anwar M, Green JA, Norris P, et al 
## Prospective daily diary study reporting of any and all symptoms in healthy 
## adults in Pakistan: prevalence and #' response
## BMJ Open 2017;7:e014998
data(symptom)
glm.symptom <- glm(actual_help_days ~ symp_days_reported, 
     family = "poisson", data = symptom)
pred.fit(glm.symptom)

Add model fit line (with SE) to GLM models (Poisson, negative binomial etc)

Description

Add model fit line (with SE) to GLM models (Poisson, negative binomial etc)

Usage

pred.plot(model, xpred = NULL, ci = 0.95)

Arguments

model

a model object, from (eg) lm glm

xpred

the predictor to be plotted on the x axis

ci

value for confidence interval (defaults to 0.95)

Value

ggplot object with fit line

Examples

#' ## Anwar M, Green JA, Norris P, et al 
## Prospective daily diary study reporting of any and all symptoms in healthy 
## adults in Pakistan: prevalence and #' response
## BMJ Open 2017;7:e014998
data(symptom)
glm.symptom <- glm(actual_help_days ~ symp_days_reported, 
     family = "poisson", data = symptom)
pred.plot(glm.symptom)

Plot simulated data from a GLM model

Description

Plot simulated data from a GLM model

Usage

sim.plot(
  model,
  xpred = NULL,
  seed = NULL,
  fit.line = TRUE,
  ci = 0.95,
  npoints = "same",
  orig_jitter = 0.1,
  sim_jitter = 0.1
)

Arguments

model

a model object, from (eg) lm glm (Poisson, Negative binomial)

xpred

the predictor to be plotted on the x axis

seed

random seed so that simulation results are replicable

fit.line

if TRUE (default) adds fit line with SE

ci

passes confidence interval width for fit curve (defaults to 0.95)

npoints

number of data points to for fit line. Either specify a number, or "same" will return a simulation of the same size as the original dataset.

orig_jitter

amount of jitter to apply to original dataset (default 0.10)

sim_jitter

amount of jitter to apply to simulated data (default 0.10)

Value

ggplot object with simulated data plotted with original

Examples

## Anwar M, Green JA, Norris P, et al 
## Prospective daily diary study reporting of any and all symptoms in healthy 
## adults in Pakistan: prevalence and #' response
## BMJ Open 2017;7:e014998
data(symptom)
glm.symptom <- glm(actual_help_days ~ symp_days_reported, 
     family = "poisson", data = symptom)
sim.plot(glm.symptom)

Responses to symptoms from a sample of the general population of Pakistan.

Description

A dataset containing the age, gender, number of days on which symptoms were experienced, number of days on which help was sought, as well as measures of impulsivity and attitudes to medicines.

Usage

symptom

Format

A data frame with 53940 rows and 10 variables:

id

participant ID, integer

age5

age in 5 year bins, (18,20) (20,25) (25,30) (30,35) (35,40) (40,45) (45,50) (50,55) (55,60) (60,65)

gender

female, male, character

bmq_spec

Pakistan adaption of Beliefs about Medicines Questionnaire (Specific) Stored as POMP score 0-100

bmq_necess

Pakistan adaption of Beliefs about Medicines Questionnaire (Necessity) Stored as POMP score 0-100

bmq_concern

Pakistan adaption of Beliefs about Medicines Questionnaire, (Concern) Stored as POMP score 0-100

bmq_general

Pakistan adaption of Beliefs about Medicines Questionnaire, (General) Stored as POMP score 0-100

bis

Pakistan adaption of Barratt Impuslivity Scale, Stored as POMP score 0-100

symp_days_reported

Number of days on which symptoms were reported, Non-negative integer (days)

actual_help_days

Number of days on which participants visited some type of health professional, Non-negative integer

Source

https://osf.io/4mjhq/

data from Anwar M, Green JA, Norris P, et al Prospective daily diary study reporting of any and all symptoms in healthy adults in Pakistan: prevalence and #' response BMJ Open 2017;7:e014998 doi:10.1136/bmjopen-2016-014998