Changes in version 2025-08-30                      

  - fixes an edge case that returned an additional column during data
    preparation for valid cases in some scenarios
  - fixes a NOTE on a non-standard file name

                     Changes in version 2025-08-22                      

  - fixes a bug / edge case where the empirical cumulative density
    function did not reach 100% for the "too cheap" distribution
  - addresses a CRAN note: proper link to page svydesign
  - fixes edge cases for plotting price points (when not present in
    original dataframe)
  - refactors code for better code quality and maintainability
  - replaces deprecated ggplot2 parameters

                     Changes in version 2024-02-25                      

  - new parameter "acceptable_range": allows to switch between van
    Westendorp's original definition of acceptable price ranges and a
    narrower definition which is used by some market research companies
  - new parameters "pi_calibrated_toocheap" and
    "pi_calibrated_tooexpensive" for functions psm_analysis() and
    psm_analysis_weighted(): allows to specify a calibrated purchase
    probability at the "too cheap" and "too expensive" price,
    respectively, which is different from zero
  - consistency: renames "trial" to "reach"

                     Changes in version 2021-10-19                      

  - psm_plot(): flexible color for Indifference Price Point and Optimal
    Price Point
  - psm_plot(): enforcing digits for Indifference Price Point and
    Optimal Price Point labels
  - change in DESCRIPTION to address a CRAN note (no need for lazy
    loading of data)

                     Changes in version 2021-03-21                      

  - fixes URL in package description
  - fixes date formatting in DESCRIPTION

  - new function psm_plot() for automatic plotting of the result
  - package now also supports input in tibble format
  - fix in plotting vignette: fix position of indifference price point
  - fixes in vignette formatting to emphasize function names
  - change of Github URLs due to change of Github username
  - fix of external URLs that have changed
  - housekeeping: re-factoring code

                     Changes in version 2019-08-23                      

  - fixes a markdown issue in the README file

                     Changes in version 2019-08-22                      

  - adds the parameter interpolation_steps that lets users define the
    granularity of the interpolation between the observed prices
  - fixes a bug that caused respondents with intransitive price
    preferences to be used in the analysis when using
    psm_analysis_weighted() (and adds some unit testing to check this in
    the future)
  - corrects the "Interpolation in Small Samples" vignette: now shows
    correctly "not cheap" instead of "cheap" and "not expensive" instead
    of "expensive"
  - extends unit test coverage

                     Changes in version 2019-04-29                      

  - makes some tests slightly more lenient to account for rounding
    differences

                     Changes in version 2019-04-28                      

  - adds the psm_analysis_weighted() function to deal with weighted
    input data. This requires the survey package.
  - adds the argument intersection_method to define how to calculate the
    price points in case there are multiple intersections (should be a
    rare case)
  - amends the psm class definition and the summary function for the psm
    class to account for weighted/unweighted data
  - bug fix: if a respondent has the same answer for both the "cheap"
    and the "expensive" price, the interpolation of purchase
    probabilities in the Newton Miller Smith extension now returns
    non-empty answers
  - bug fix: if "too cheap" information is missing, skip some
    calculations

                     Changes in version 2018-10-21                      

  - fixes issue with calculation of "point of marginal cheapness" and
    "point of marginal expensiveness" (acceptable price range). also
    affects documentation and visualization vignette. thanks to athib2
    for flagging it
  - fixes bug in calculation of % of removed cases (did show only 0/1
    before, now proper percentages)
  - fixes typos in summary() function and in the documentation
  - adds unit testing for Newton Miller Smith input as dataframe

                     Changes in version 2018-10-14                      

  - fixes an issue in the unit testing with an if condition with length
    greater 1 (thanks to Tomas Kalibera for automated testing in
    R-devel)

                     Changes in version 2018-05-12                      

  - changing links from http://... to https://...

                     Changes in version 2018-05-10                      

  - adding optional argument to interpolate between price points
  - adding a vignette for the interpolate argument
  - edits in the README: fixing typos, amending the installation
    instructions

                     Changes in version 2018-04-12                      

  - addressing feedback from CRAN submit: adding proper citation of the
    main publication in the DESCRIPTION file

                     Changes in version 2018-04-11                      

  - adding support for running the analysis without a "too cheap" price
  - adding a charting vignette
  - adding automated testing of function inputs and function outputs
  - renaming the main function from "PSManalysis" to "psm_analysis" (for
    readability reasons)
  - improving smoothing of trial/revenue optimization when using Newton
    Miller Smith extension: setting up the price matrix with continuous
    price steps between the minimum and the maximum to avoid jumps that
    come from the lack of price points in a specific area
  - refining the data input checks (resulting from the c()
    implementation of hierarchies between data classes)

                     Changes in version 2017-05-20                      

  - first complete Github version incl. function documentation