---
_id: '20870'
abstract:
- lang: eng
  text: This study shows how venture capital investors can identify potential biases
    in multi-year management forecasts before an investment decision and derive significantly
    more accurate failure predictions. By advancing a cross-sectional projection method
    developed by prior research and using firm-specific information in financial statements
    and business plans, we derive benchmarks for management revenue forecasts. With
    these benchmarks, we estimate forecast errors as an a priori measure of biased
    expectations. Using this measure for our proprietary dataset on venture-backed
    start-ups in Germany, we find evidence of substantial upward forecast biases.
    We uncover that firms with large forecast errors fail significantly more often
    than do less biased entrepreneurs in years following the investment. Overall,
    our results highlight the implications of excessive optimism and overconfidence
    in entrepreneurial environments and emphasize the relevance of accounting information
    and business plans for venture capital investment decisions.
author:
- first_name: Sönke
  full_name: Sievers, Sönke
  id: '46447'
  last_name: Sievers
- first_name: Christopher Frederik
  full_name: Mokwa, Christopher Frederik
  last_name: Mokwa
citation:
  ama: Sievers S, Mokwa CF. <i>The Relevance of Biases in Management Forecasts for
    Failure Prediction in Venture Capital Investments</i>.; 2012. doi:<a href="https://doi.org/10.2139/ssrn.2100501">10.2139/ssrn.2100501</a>
  apa: Sievers, S., &#38; Mokwa, C. F. (2012). <i>The Relevance of Biases in Management
    Forecasts for Failure Prediction in Venture Capital Investments</i>. <a href="https://doi.org/10.2139/ssrn.2100501">https://doi.org/10.2139/ssrn.2100501</a>
  bibtex: '@book{Sievers_Mokwa_2012, title={The Relevance of Biases in Management
    Forecasts for Failure Prediction in Venture Capital Investments}, DOI={<a href="https://doi.org/10.2139/ssrn.2100501">10.2139/ssrn.2100501</a>},
    author={Sievers, Sönke and Mokwa, Christopher Frederik}, year={2012} }'
  chicago: Sievers, Sönke, and Christopher Frederik Mokwa. <i>The Relevance of Biases
    in Management Forecasts for Failure Prediction in Venture Capital Investments</i>,
    2012. <a href="https://doi.org/10.2139/ssrn.2100501">https://doi.org/10.2139/ssrn.2100501</a>.
  ieee: S. Sievers and C. F. Mokwa, <i>The Relevance of Biases in Management Forecasts
    for Failure Prediction in Venture Capital Investments</i>. 2012.
  mla: Sievers, Sönke, and Christopher Frederik Mokwa. <i>The Relevance of Biases
    in Management Forecasts for Failure Prediction in Venture Capital Investments</i>.
    2012, doi:<a href="https://doi.org/10.2139/ssrn.2100501">10.2139/ssrn.2100501</a>.
  short: S. Sievers, C.F. Mokwa, The Relevance of Biases in Management Forecasts for
    Failure Prediction in Venture Capital Investments, 2012.
date_created: 2021-01-05T11:59:50Z
date_updated: 2022-01-06T06:54:41Z
department:
- _id: '275'
doi: 10.2139/ssrn.2100501
extern: '1'
jel:
- G24
- G32
- M13
- M41
keyword:
- Management forecast biases
- cross-sectional projection models
- venture-backed start-ups
- failure prediction
- overoptimism
- overconfidence
language:
- iso: eng
main_file_link:
- url: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2100501
page: '31'
publication_status: published
status: public
title: The Relevance of Biases in Management Forecasts for Failure Prediction in Venture
  Capital Investments
type: working_paper
user_id: '46447'
year: '2012'
...
---
_id: '5196'
abstract:
- lang: eng
  text: 'This study shows how venture capital investors can identify potential biases
    in multi-year management forecasts before an investment decision and derive significantly
    more accurate failure predictions. By advancing a cross-sectional projection method
    developed by prior research and using firm-specific information in financial statements
    and business plans, we derive benchmarks for management revenue forecasts. With
    these benchmarks, we estimate forecast errors as an a priori measure of biased
    expectations. Using this measure for our proprietary dataset on venture-backed
    start-ups in Germany, we find evidence of substantial upward forecast biases.
    We uncover that firms with large forecast errors fail significantly more often
    than do less biased entrepreneurs in years following the investment. Overall,
    our results highlight the implications of excessive optimism and overconfidence
    in entrepreneurial environments and emphasize the relevance of accounting information
    and business plans for venture capital investment decisions. '
author:
- first_name: Christopher Frederik
  full_name: Mokwa, Christopher Frederik
  last_name: Mokwa
- first_name: Sönke
  full_name: Sievers, Sönke
  last_name: Sievers
citation:
  ama: Mokwa CF, Sievers S. The Relevance of Biases in Management Forecasts for Failure
    Prediction in Venture Capital Investments. <i>SSRN Electronic Journal</i>. 2012.
    doi:<a href="https://doi.org/10.2139/ssrn.2100501">10.2139/ssrn.2100501</a>
  apa: Mokwa, C. F., &#38; Sievers, S. (2012). The Relevance of Biases in Management
    Forecasts for Failure Prediction in Venture Capital Investments. <i>SSRN Electronic
    Journal</i>. <a href="https://doi.org/10.2139/ssrn.2100501">https://doi.org/10.2139/ssrn.2100501</a>
  bibtex: '@article{Mokwa_Sievers_2012, title={The Relevance of Biases in Management
    Forecasts for Failure Prediction in Venture Capital Investments}, DOI={<a href="https://doi.org/10.2139/ssrn.2100501">10.2139/ssrn.2100501</a>},
    journal={SSRN Electronic Journal}, author={Mokwa, Christopher Frederik and Sievers,
    Sönke}, year={2012} }'
  chicago: Mokwa, Christopher Frederik, and Sönke Sievers. “The Relevance of Biases
    in Management Forecasts for Failure Prediction in Venture Capital Investments.”
    <i>SSRN Electronic Journal</i>, 2012. <a href="https://doi.org/10.2139/ssrn.2100501">https://doi.org/10.2139/ssrn.2100501</a>.
  ieee: C. F. Mokwa and S. Sievers, “The Relevance of Biases in Management Forecasts
    for Failure Prediction in Venture Capital Investments,” <i>SSRN Electronic Journal</i>,
    2012.
  mla: Mokwa, Christopher Frederik, and Sönke Sievers. “The Relevance of Biases in
    Management Forecasts for Failure Prediction in Venture Capital Investments.” <i>SSRN
    Electronic Journal</i>, 2012, doi:<a href="https://doi.org/10.2139/ssrn.2100501">10.2139/ssrn.2100501</a>.
  short: C.F. Mokwa, S. Sievers, SSRN Electronic Journal (2012).
date_created: 2018-10-31T12:12:28Z
date_updated: 2022-01-06T07:01:43Z
department:
- _id: '275'
doi: 10.2139/ssrn.2100501
jel:
- G24
- G32
- M13
- M41
keyword:
- Management forecast biases
- cross-sectional projection models
- venture-backed start-ups
- failure prediction
- overoptimism
- overconfidence
language:
- iso: eng
publication: SSRN Electronic Journal
publication_status: published
status: public
title: The Relevance of Biases in Management Forecasts for Failure Prediction in Venture
  Capital Investments
type: journal_article
user_id: '64756'
year: '2012'
...
---
_id: '13326'
abstract:
- lang: eng
  text: Communication within online social network applications enables users to express
    and share sentiments electronically. Existing studies examined the existence or
    distribution of sentiments in online communication at a general level or in small-observed
    groups. Our paper extends this research by analyzing sentiment exchange within
    social networks from an ego-network perspective. We draw from research on social
    influence and social attachment to develop theories of node polarization, balance
    effects and sentiment mirroring within communication dyads. Our empirical analysis
    covers a multitude of social networks in which the sentiment valence of all messages
    was determined. Subsequently we studied ego-networks of focal actors (ego) and
    their immediate contacts. Results support our theories and indicate that actors
    develop polarized sentiments towards individual peers but keep sentiment in balance
    on the ego-network level. Further, pairs of nodes tend to establish similar attitudes
    towards each other leading to stable and polarized positive or negative relationships
author:
- first_name: Robert
  full_name: Hillmann, Robert
  last_name: Hillmann
- first_name: Matthias
  full_name: Trier, Matthias
  id: '72744'
  last_name: Trier
citation:
  ama: 'Hillmann R, Trier M. Sentiment Polarization and Balance among Users in Online
    Social Networks. In: Joshi KD, Yoo Y, eds. <i>AMCIS 2012 Proceedings</i>. Vol
    24. Association for Information Systems. AIS Electronic Library (AISeL); 2012.'
  apa: Hillmann, R., &#38; Trier, M. (2012). Sentiment Polarization and Balance among
    Users in Online Social Networks. In K. D. Joshi &#38; Y. Yoo (Eds.), <i>AMCIS
    2012 Proceedings</i> (Vol. 24). Association for Information Systems. AIS Electronic
    Library (AISeL).
  bibtex: '@inproceedings{Hillmann_Trier_2012, title={Sentiment Polarization and Balance
    among Users in Online Social Networks}, volume={24}, booktitle={AMCIS 2012 Proceedings},
    publisher={Association for Information Systems. AIS Electronic Library (AISeL)},
    author={Hillmann, Robert and Trier, Matthias}, editor={Joshi, K.D. and Yoo, YoungjinEditors},
    year={2012} }'
  chicago: Hillmann, Robert, and Matthias Trier. “Sentiment Polarization and Balance
    among Users in Online Social Networks.” In <i>AMCIS 2012 Proceedings</i>, edited
    by K.D. Joshi and Youngjin Yoo, Vol. 24. Association for Information Systems.
    AIS Electronic Library (AISeL), 2012.
  ieee: R. Hillmann and M. Trier, “Sentiment Polarization and Balance among Users
    in Online Social Networks,” in <i>AMCIS 2012 Proceedings</i>, 2012, vol. 24.
  mla: Hillmann, Robert, and Matthias Trier. “Sentiment Polarization and Balance among
    Users in Online Social Networks.” <i>AMCIS 2012 Proceedings</i>, edited by K.D.
    Joshi and Youngjin Yoo, vol. 24, Association for Information Systems. AIS Electronic
    Library (AISeL), 2012.
  short: 'R. Hillmann, M. Trier, in: K.D. Joshi, Y. Yoo (Eds.), AMCIS 2012 Proceedings,
    Association for Information Systems. AIS Electronic Library (AISeL), 2012.'
date_created: 2019-09-19T12:22:08Z
date_updated: 2022-01-06T06:51:33Z
department:
- _id: '198'
editor:
- first_name: K.D.
  full_name: Joshi, K.D.
  last_name: Joshi
- first_name: Youngjin
  full_name: Yoo, Youngjin
  last_name: Yoo
intvolume: '        24'
keyword:
- Social Network Analysis
- Ego-Network Analysis
- Node Polarization
- Sentiment Dissemination
language:
- iso: eng
publication: AMCIS 2012 Proceedings
publisher: Association for Information Systems. AIS Electronic Library (AISeL)
status: public
title: Sentiment Polarization and Balance among Users in Online Social Networks
type: conference
user_id: '62809'
volume: 24
year: '2012'
...
---
_id: '11930'
abstract:
- lang: eng
  text: For human-machine interfaces in distant-talking environments multichannel
    signal processing is often employed to obtain an enhanced signal for subsequent
    processing. In this paper we propose a novel adaptation algorithm for a filter-and-sum
    beamformer to adjust the coefficients of FIR filters to changing acoustic room
    impulses, e.g. due to speaker movement. A deterministic and a stochastic gradient
    ascent algorithm are derived from a constrained optimization problem, which iteratively
    estimates the eigenvector corresponding to the largest eigenvalue of the cross
    power spectral density of the microphone signals. The method does not require
    an explicit estimation of the speaker location. The experimental results show
    fast adaptation and excellent robustness of the proposed algorithm.
author:
- first_name: Ernst
  full_name: Warsitz, Ernst
  last_name: Warsitz
- first_name: Reinhold
  full_name: Haeb-Umbach, Reinhold
  id: '242'
  last_name: Haeb-Umbach
citation:
  ama: 'Warsitz E, Haeb-Umbach R. Acoustic filter-and-sum beamforming by adaptive
    principal component analysis. In: <i>IEEE International Conference on Acoustics,
    Speech and Signal Processing (ICASSP 2005)</i>. Vol 4. ; 2005:iv/797-iv/800 Vol.
    4. doi:<a href="https://doi.org/10.1109/ICASSP.2005.1416129">10.1109/ICASSP.2005.1416129</a>'
  apa: Warsitz, E., &#38; Haeb-Umbach, R. (2005). Acoustic filter-and-sum beamforming
    by adaptive principal component analysis. In <i>IEEE International Conference
    on Acoustics, Speech and Signal Processing (ICASSP 2005)</i> (Vol. 4, p. iv/797-iv/800
    Vol. 4). <a href="https://doi.org/10.1109/ICASSP.2005.1416129">https://doi.org/10.1109/ICASSP.2005.1416129</a>
  bibtex: '@inproceedings{Warsitz_Haeb-Umbach_2005, title={Acoustic filter-and-sum
    beamforming by adaptive principal component analysis}, volume={4}, DOI={<a href="https://doi.org/10.1109/ICASSP.2005.1416129">10.1109/ICASSP.2005.1416129</a>},
    booktitle={IEEE International Conference on Acoustics, Speech and Signal Processing
    (ICASSP 2005)}, author={Warsitz, Ernst and Haeb-Umbach, Reinhold}, year={2005},
    pages={iv/797-iv/800 Vol. 4} }'
  chicago: Warsitz, Ernst, and Reinhold Haeb-Umbach. “Acoustic Filter-and-Sum Beamforming
    by Adaptive Principal Component Analysis.” In <i>IEEE International Conference
    on Acoustics, Speech and Signal Processing (ICASSP 2005)</i>, 4:iv/797-iv/800
    Vol. 4, 2005. <a href="https://doi.org/10.1109/ICASSP.2005.1416129">https://doi.org/10.1109/ICASSP.2005.1416129</a>.
  ieee: E. Warsitz and R. Haeb-Umbach, “Acoustic filter-and-sum beamforming by adaptive
    principal component analysis,” in <i>IEEE International Conference on Acoustics,
    Speech and Signal Processing (ICASSP 2005)</i>, 2005, vol. 4, p. iv/797-iv/800
    Vol. 4.
  mla: Warsitz, Ernst, and Reinhold Haeb-Umbach. “Acoustic Filter-and-Sum Beamforming
    by Adaptive Principal Component Analysis.” <i>IEEE International Conference on
    Acoustics, Speech and Signal Processing (ICASSP 2005)</i>, vol. 4, 2005, p. iv/797-iv/800
    Vol. 4, doi:<a href="https://doi.org/10.1109/ICASSP.2005.1416129">10.1109/ICASSP.2005.1416129</a>.
  short: 'E. Warsitz, R. Haeb-Umbach, in: IEEE International Conference on Acoustics,
    Speech and Signal Processing (ICASSP 2005), 2005, p. iv/797-iv/800 Vol. 4.'
date_created: 2019-07-12T05:31:00Z
date_updated: 2022-01-06T06:51:12Z
department:
- _id: '54'
doi: 10.1109/ICASSP.2005.1416129
intvolume: '         4'
keyword:
- acoustic filter-and-sum beamforming
- acoustic room impulses
- acoustic signal processing
- adaptive principal component analysis
- adaptive signal processing
- architectural acoustics
- constrained optimization problem
- cross power spectral density
- deterministic algorithm
- deterministic algorithms
- distant-talking environments
- eigenvalues and eigenfunctions
- eigenvector
- enhanced signal
- filter-and-sum beamformer
- FIR filter coefficients
- FIR filter coefficients
- FIR filters
- gradient methods
- human-machine interfaces
- iterative estimation
- iterative methods
- largest eigenvalue
- microphone signals
- multichannel signal processing
- optimisation
- principal component analysis
- spectral analysis
- stochastic gradient ascent algorithm
- stochastic processes
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://groups.uni-paderborn.de/nt/pubs/2005/WaHa05.pdf
oa: '1'
page: iv/797-iv/800 Vol. 4
publication: IEEE International Conference on Acoustics, Speech and Signal Processing
  (ICASSP 2005)
status: public
title: Acoustic filter-and-sum beamforming by adaptive principal component analysis
type: conference
user_id: '44006'
volume: 4
year: '2005'
...
---
_id: '11931'
abstract:
- lang: eng
  text: The paper is concerned with binaural signal processing for a bimodal human-robot
    interface with hearing and vision. The two microphone signals are processed to
    obtain an enhanced single-channel input signal for the subsequent speech recognizer
    and to localize the acoustic source, an important information for establishing
    a natural human-robot communication. We utilize a robust adaptive algorithm for
    filter-and-sum beamforming (FSB) and extract speaker direction information from
    the resulting FIR filter coefficients. Further, particle filtering is applied
    which conducts a nonlinear Bayesian tracking of speaker movement. Good location
    accuracy can be achieved even in highly reverberant environments. The results
    obtained outperform the conventional generalized cross correlation (GCC) method.
author:
- first_name: Ernst
  full_name: Warsitz, Ernst
  last_name: Warsitz
- first_name: Reinhold
  full_name: Haeb-Umbach, Reinhold
  id: '242'
  last_name: Haeb-Umbach
citation:
  ama: 'Warsitz E, Haeb-Umbach R. Robust speaker direction estimation with particle
    filtering. In: <i>IEEE Workshop on Multimedia Signal Processing (MMSP 2004)</i>.
    ; 2004:367-370. doi:<a href="https://doi.org/10.1109/MMSP.2004.1436569">10.1109/MMSP.2004.1436569</a>'
  apa: Warsitz, E., &#38; Haeb-Umbach, R. (2004). Robust speaker direction estimation
    with particle filtering. In <i>IEEE Workshop on Multimedia Signal Processing (MMSP
    2004)</i> (pp. 367–370). <a href="https://doi.org/10.1109/MMSP.2004.1436569">https://doi.org/10.1109/MMSP.2004.1436569</a>
  bibtex: '@inproceedings{Warsitz_Haeb-Umbach_2004, title={Robust speaker direction
    estimation with particle filtering}, DOI={<a href="https://doi.org/10.1109/MMSP.2004.1436569">10.1109/MMSP.2004.1436569</a>},
    booktitle={IEEE Workshop on Multimedia Signal Processing (MMSP 2004)}, author={Warsitz,
    Ernst and Haeb-Umbach, Reinhold}, year={2004}, pages={367–370} }'
  chicago: Warsitz, Ernst, and Reinhold Haeb-Umbach. “Robust Speaker Direction Estimation
    with Particle Filtering.” In <i>IEEE Workshop on Multimedia Signal Processing
    (MMSP 2004)</i>, 367–70, 2004. <a href="https://doi.org/10.1109/MMSP.2004.1436569">https://doi.org/10.1109/MMSP.2004.1436569</a>.
  ieee: E. Warsitz and R. Haeb-Umbach, “Robust speaker direction estimation with particle
    filtering,” in <i>IEEE Workshop on Multimedia Signal Processing (MMSP 2004)</i>,
    2004, pp. 367–370.
  mla: Warsitz, Ernst, and Reinhold Haeb-Umbach. “Robust Speaker Direction Estimation
    with Particle Filtering.” <i>IEEE Workshop on Multimedia Signal Processing (MMSP
    2004)</i>, 2004, pp. 367–70, doi:<a href="https://doi.org/10.1109/MMSP.2004.1436569">10.1109/MMSP.2004.1436569</a>.
  short: 'E. Warsitz, R. Haeb-Umbach, in: IEEE Workshop on Multimedia Signal Processing
    (MMSP 2004), 2004, pp. 367–370.'
date_created: 2019-07-12T05:31:01Z
date_updated: 2022-01-06T06:51:12Z
department:
- _id: '54'
doi: 10.1109/MMSP.2004.1436569
keyword:
- bimodal human-robot interface
- binaural signal processing
- enhanced single-channel input signal
- filter-and-sum beamforming
- filtering theory
- FIR filter coefficient
- generalized cross correlation method
- microphones
- microphone signal
- nonlinear Bayesian tracking
- particle filtering
- robust adaptive algorithm
- robust speaker direction estimation
- signal processing
- speech enhancement
- speech recognition
- speech recognizer
- user interfaces
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://groups.uni-paderborn.de/nt/pubs/2004/WaHa04.pdf
oa: '1'
page: 367-370
publication: IEEE Workshop on Multimedia Signal Processing (MMSP 2004)
status: public
title: Robust speaker direction estimation with particle filtering
type: conference
user_id: '44006'
year: '2004'
...
